{"title":"Explore Scientific Refractors","description":"\u003cp\u003eExplore Scientific refractors span the AR air-spaced doublets (AR102, AR127, AR152), Essential and FCD100 air-spaced triplet APOs from 80 to 152mm including carbon fibre tubes, and the Sidara range of complete telescopes on alt-azimuth or GoTo mounts. Several ED80 and ED102 triplets are also packaged with a focal reducer or field flattener and an iEXOS-100-2 PMC-Eight GoTo mount. Part of \u003ca href=\"\/collections\/refractors\"\u003eRefractor Telescopes\u003c\/a\u003e.\u003c\/p\u003e","products":[{"product_id":"explore-scientific-ar152mm-f-6-5-refractor","title":"Explore Scientific AR152 152mm f\/6.5 Air-Spaced Doublet Refractor (OTA)","description":"\u003ch3\u003e\u003cstrong\u003eProduct Overview\u003c\/strong\u003e\u003c\/h3\u003e\n\u003cp\u003eThe Explore Scientific AR152 is a 152mm (6-inch) air-spaced crown-and-flint achromatic doublet refractor with a native focal length of 988mm at f\/6.5. It is the largest aperture in the AR Series, and at this focal ratio it is built around wide, bright, low-power views rather than long-focus planetary work.\u003c\/p\u003e\n\u003cp\u003eIt is sold as an optical tube assembly with its accessory package — a 2-inch dual-speed focuser, a one-piece 2-inch dielectric diagonal, an 8x50 finderscope on the Hybrid 2N1 base, and a cradle ring set with a 45mm V-block dovetail. No mount and no eyepieces are included.\u003c\/p\u003e\n\n\u003ch3\u003e\u003cstrong\u003eWho It's For\u003c\/strong\u003e\u003c\/h3\u003e\n\u003cul\u003e\n\u003cli\u003e\n\u003cstrong\u003eVisual deep-sky observers:\u003c\/strong\u003e 152mm of aperture at f\/6.5 gathers roughly 470x the light of the naked eye, with a stated limiting magnitude of 13.4 and 0.77 arcsec resolution.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eWide-field observers:\u003c\/strong\u003e at 988mm with a 2-inch focuser, large open clusters, the Veil and the Andromeda halo fit in a single field in a way a long-focus instrument cannot manage.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eOutreach and public star parties:\u003c\/strong\u003e the accessory package is specified for heavy handling, and a refractor needs no collimation between events.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eObservers moving up in aperture\u003c\/strong\u003e who want a refractor's contrast and zero-maintenance optics rather than a reflector's. This is a good match if you already have a mount rated well above 23 lb and want the largest achromat that mount will carry.\u003c\/li\u003e\n\u003c\/ul\u003e\n\n\u003ch3\u003e\u003cstrong\u003eKey Features \u0026amp; Design\u003c\/strong\u003e\u003c\/h3\u003e\n\u003cul\u003e\n\u003cli\u003e\n\u003cstrong\u003e152mm air-spaced doublet:\u003c\/strong\u003e crown-and-flint achromat, air-spaced rather than cemented.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003e988mm focal length, f\/6.5:\u003c\/strong\u003e a fast focal ratio for a 6-inch refractor, which is what keeps the tube and the true field manageable.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003e2″ dual-speed focuser:\u003c\/strong\u003e coarse and fine control on the same knob for setting focus at high power.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eOne-piece 2″ diagonal with 99% dielectric coatings:\u003c\/strong\u003e included, not an upsell.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eHybrid 2N1 finder scope base:\u003c\/strong\u003e takes both finder-shoe standards, with an 8x50 non-illuminated straight-through finderscope and quick-release bracket supplied.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eCradle ring set with 45mm wide V-block dovetail,\u003c\/strong\u003e similar to the Vixen dovetail standard.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003ePublished weight 23 lb (10.7 kg)\u003c\/strong\u003e for the tube assembly, and 41″ (1041mm) long with the dew shield extended.\u003c\/li\u003e\n\u003c\/ul\u003e\n\n\u003ch3\u003e\u003cstrong\u003eOptical Design\u003c\/strong\u003e\u003c\/h3\u003e\n\u003cp\u003eAn air-spaced achromatic doublet brings two wavelengths to a common focus using a crown element and a flint element separated by an air gap. The air gap gives the designer two extra optical surfaces to work with compared to a cemented doublet, and it removes the cement layer as a thermal and optical variable in a large lens — which matters more at 152mm than at 80mm.\u003c\/p\u003e\n\u003cp\u003eAn achromat is not an apochromat, and the difference is visible on the brightest targets: Venus, Jupiter, Sirius and the limb of the Moon will show some colour fringing at high power, which is inherent to two-element crown-and-flint designs rather than a defect in this one. On extended deep-sky objects, star clusters and low-power sweeping it is not a factor, and that is the observing this focal ratio is built for. Observers who want to reduce it at high power typically add a fringe-killer or minus-violet filter; if you want the colour gone entirely rather than reduced, an ED or apochromatic triplet is the design to look at, and we stock those.\u003c\/p\u003e\n\u003cp\u003eThe 41-inch tube with the dew shield out, at 23 lb bare, is a substantial optical tube. The 45mm V-block dovetail spreads that load across the cradle rings rather than concentrating it at a single saddle point.\u003c\/p\u003e\n\n\u003ch3\u003e\u003cstrong\u003eRecommended Uses\u003c\/strong\u003e\u003c\/h3\u003e\n\u003cul\u003e\n\u003cli\u003eLow and medium-power visual observing of open clusters, nebulae and the brighter galaxies.\u003c\/li\u003e\n\u003cli\u003eLunar and planetary observing at moderate magnification.\u003c\/li\u003e\n\u003cli\u003eDouble-star work, where 0.77 arcsec resolution is the governing figure.\u003c\/li\u003e\n\u003cli\u003ePublic outreach and educational sessions.\u003c\/li\u003e\n\u003cli\u003eWide-field and solar-system astrophotography on a suitably rated equatorial mount.\u003c\/li\u003e\n\u003c\/ul\u003e\n\n\u003ch3\u003e\u003cstrong\u003eCompatibility and Accessory Notes\u003c\/strong\u003e\u003c\/h3\u003e\n\u003cul\u003e\n\u003cli\u003e\n\u003cstrong\u003eMount:\u003c\/strong\u003e not included. The published tube weight is 23 lb before the diagonal, finder and eyepiece, so the loaded tube sits higher. For visual use a mount rated at 30 lb or more is the sensible starting point; for imaging, more again.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eDovetail:\u003c\/strong\u003e the 45mm wide V-block fits Vixen-style saddles. A saddle that takes both Vixen and Losmandy plates will accept it.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eEyepieces:\u003c\/strong\u003e none included. The 2-inch focuser and diagonal take both 2-inch and, with the supplied adapter, 1.25-inch eyepieces. At 988mm, a 30mm eyepiece gives 33x and a 9mm gives 110x.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eFinder:\u003c\/strong\u003e the Hybrid 2N1 base accepts finder shoes of both common patterns, so an illuminated or right-angle finder can replace the supplied 8x50 without changing the base.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eFilters:\u003c\/strong\u003e the 2-inch diagonal accepts 2-inch threaded filters. A minus-violet or fringe-killer filter is the usual pairing for high-power lunar and planetary work with a fast achromat.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eImaging:\u003c\/strong\u003e a field flattener is needed for anything approaching a flat field across an APS-C sensor. Explore Scientific does not publish a corrected image circle for this tube, so we do not quote one — send us your camera and we will confirm what fits.\u003c\/li\u003e\n\u003c\/ul\u003e\n\n\u003ch3\u003e\u003cstrong\u003eGood to Know Before You Order\u003c\/strong\u003e\u003c\/h3\u003e\n\u003cul\u003e\n\u003cli\u003e\n\u003cstrong\u003eThis is an optical tube assembly, not a complete telescope.\u003c\/strong\u003e A mount and tripod are needed to use it, and so is at least one eyepiece. We can put a package together if it is easier — just ask.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eIt is a 23 lb, 41-inch tube.\u003c\/strong\u003e That is a two-hands instrument to carry and mount, and it wants a mount with real capacity underneath it. Worth accounting for if you set up and tear down each session.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eAchromatic, not apochromatic.\u003c\/strong\u003e Some colour on the brightest objects at high power comes with the design. A minus-violet filter reduces it, and at the low and medium powers this focal ratio is built for it is not the limiting factor.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eDew shield length is included in the 41-inch figure.\u003c\/strong\u003e Check it against your case or vehicle before ordering if transport is a consideration.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eExplore Scientific publishes no corrected image circle or backfocus figure\u003c\/strong\u003e for this tube, so those rows are absent from the specifications rather than estimated. If you are planning an imaging train, send us the camera and flattener you have in mind and we will work out the spacing with you.\u003c\/li\u003e\n\u003c\/ul\u003e\n\n\u003ch3\u003e\u003cstrong\u003eFrequently Asked Questions\u003c\/strong\u003e\u003c\/h3\u003e\n\u003cp\u003e\u003cstrong\u003eIs it difficult to set up?\u003c\/strong\u003e\u003c\/p\u003e\n\u003cp\u003eThe telescope itself is straightforward — a refractor needs no collimation, so it is ready as soon as it is on the mount. The work is in the handling: at 23 lb and 41 inches it takes two hands to lift onto a saddle, and it is easier with the mount already levelled and balanced.\u003c\/p\u003e\n\u003cp\u003e\u003cstrong\u003eWhat mount do I need?\u003c\/strong\u003e\u003c\/p\u003e\n\u003cp\u003eOne rated comfortably above the loaded tube weight. 23 lb bare becomes more once the diagonal, finder and a 2-inch eyepiece are on it, so 30 lb of rated visual capacity is a reasonable floor. Tell us what you have and we will tell you honestly whether it will carry this.\u003c\/p\u003e\n\u003cp\u003e\u003cstrong\u003eDoes it come with eyepieces?\u003c\/strong\u003e\u003c\/p\u003e\n\u003cp\u003eNo. The 2-inch diagonal, 8x50 finder and cradle rings are included; eyepieces are chosen separately.\u003c\/p\u003e\n\u003cp\u003e\u003cstrong\u003eWill I see colour fringing?\u003c\/strong\u003e\u003c\/p\u003e\n\u003cp\u003eOn Venus, Jupiter, Sirius and the lunar limb at high magnification, yes — that is what an achromatic doublet does. On clusters, nebulae and galaxies at the low to medium powers this scope is built for, it is not something you notice.\u003c\/p\u003e\n\u003cp\u003e\u003cstrong\u003eCan I image with it?\u003c\/strong\u003e\u003c\/p\u003e\n\u003cp\u003eFor the Moon, planets and wide-field work on a properly rated equatorial mount, yes. For deep-sky imaging it needs a field flattener, and the achromatic design will record more colour around bright stars than an ED or apochromatic tube would.\u003c\/p\u003e\n\u003cp\u003e\u003cstrong\u003eHow does it compare to the AR102 and AR127?\u003c\/strong\u003e\u003c\/p\u003e\n\u003cp\u003eSame optical design and same f\/6.5 focal ratio, scaled up. The AR152 gathers the most light and resolves the finest detail of the three, at 23 lb against the smaller tubes' lighter weights. Aperture and portability trade directly against each other across the series.\u003c\/p\u003e\n\n\u003ch3\u003e\u003cstrong\u003eBottom Line\u003c\/strong\u003e\u003c\/h3\u003e\n\u003cp\u003eIn short: a 152mm f\/6.5 air-spaced achromat supplied as a tube assembly with a 2-inch dual-speed focuser, dielectric diagonal, 8x50 finder and Vixen-style dovetail — a wide-field, low-maintenance six inches of aperture that needs a mount rated well above its 23 lb. If you are matching it to a mount you already own, send us the model and we will confirm the fit before you order.\u003c\/p\u003e\n","brand":"Explore Scientific","offers":[{"title":"Default Title","offer_id":44012381896815,"sku":"DAR152065-02","price":1198.95,"currency_code":"CAD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0686\/0049\/6239\/files\/ar_152.jpg?v=1785874882"},{"product_id":"explore-scientific-127mm-doublet-refractor","title":"Explore Scientific AR127 127mm f\/6.5 Air-Spaced Doublet Refractor Telescope","description":"\u003ch3\u003e\u003cstrong\u003eProduct Overview\u003c\/strong\u003e\u003c\/h3\u003e\n\u003cp\u003eThe Explore Scientific AR127 is a 127mm air-spaced crown-and-flint achromatic doublet refractor with a published focal length of 826mm at f\/6.5. That focal ratio is the defining number on this tube: a five-inch achromat built in the classic long-focus tradition would run well over a metre and a half, while the AR127 measures 34″ (863mm) with the dew shield in place and 130mm across the tube.\u003c\/p\u003e\n\u003cp\u003eExplore Scientific publishes a limiting magnitude of 13 and a resolution of .9 arcsec for this objective, and lists the tube assembly at 15.6lb (7.1kg). At 127mm the objective gathers roughly 330 times the light of a dark-adapted eye, which is what puts magnitude 13 within reach on a good night. The tube is aluminium and stainless steel in gloss white, and the optical surfaces carry EMD (Enhanced Multi-Layer Deposition) coatings.\u003c\/p\u003e\n\u003cp\u003eIt arrives as an optical tube assembly with its accessory package: a heavy-duty 2-inch dual-speed Crayford-style focuser, a one-piece 2-inch diagonal with 99% dielectric coatings and a 1.25-inch compression-ring adapter, an 8x50 straight-through finderscope with a 6° field and quick-release bracket, and an extruded aluminium cradle ring assembly on a Vixen-style plate. Mount, tripod and eyepieces are chosen separately.\u003c\/p\u003e\n\n\u003ch3\u003e\u003cstrong\u003eWho It's For\u003c\/strong\u003e\u003c\/h3\u003e\n\u003cul\u003e\n\u003cli\u003e\n\u003cstrong\u003eWide-field visual observers:\u003c\/strong\u003e 826mm with a 2-inch focuser puts large open clusters, the Double Cluster and the sweep of the Milky Way in a single field. A 30mm eyepiece works out to 27.5x here, which is genuinely low power for five inches of aperture.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eObservers who want aperture without maintenance:\u003c\/strong\u003e a refractor holds its collimation, so there is no mirror to align before a session and no open tube to collect dust.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eThis is a good match if\u003c\/strong\u003e you already own a mount with real capacity to spare and want the largest achromat that mount will carry comfortably at 15.6lb before accessories.\u003c\/li\u003e\n\u003c\/ul\u003e\n\n\u003ch3\u003e\u003cstrong\u003eKey Features \u0026amp; Design\u003c\/strong\u003e\u003c\/h3\u003e\n\u003cul\u003e\n\u003cli\u003e\n\u003cstrong\u003e127mm air-spaced doublet:\u003c\/strong\u003e crown and flint elements separated by an air gap rather than cemented together, on research-grade diffraction-limited surfaces.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003e826mm focal length at f\/6.5:\u003c\/strong\u003e short for the aperture, which is what keeps the tube to 34″ and the true field wide.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003e2″ dual-speed Crayford-style focuser:\u003c\/strong\u003e coarse and fine motion on concentric knobs, which is what makes focus repeatable at higher magnifications.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eOne-piece 2″ diagonal with 99% dielectric coatings,\u003c\/strong\u003e supplied with the telescope along with a 1.25-inch compression-ring adapter.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003e8x50 straight-through finderscope\u003c\/strong\u003e with a wide 6° field, front objective focus and a quick-release bracket.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eCradle ring assembly and universal adjustable mounting plate:\u003c\/strong\u003e the Vixen-style plate fits saddles from Explore Scientific, Meade, Celestron, Vixen and others.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eUser-serviceable lens cell:\u003c\/strong\u003e refractors rarely need collimation after factory adjustment, and the cell design allows it to be done at home.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003ePublished dimensions:\u003c\/strong\u003e 130mm tube diameter, 34″ (863mm) length with the dew shield, 15.6lb (7.1kg) assembly weight.\u003c\/li\u003e\n\u003c\/ul\u003e\n\n\u003ch3\u003e\u003cstrong\u003eOptical Design\u003c\/strong\u003e\u003c\/h3\u003e\n\u003cp\u003eAn achromatic doublet brings two wavelengths of light to a common focus by pairing a crown-glass element with a flint-glass element of opposing dispersion. Air-spacing the two, rather than cementing them, gives the designer four working surfaces instead of two and removes the cement layer as a thermal variable inside a 127mm lens. It also lets the cell hold each element independently, which is part of why consumer collimation is possible on this tube at all.\u003c\/p\u003e\n\u003cp\u003eAn achromat is not an apochromat, and at f\/6.5 the difference shows on the brightest targets. Venus, Jupiter, Sirius and the lunar limb will carry a violet edge at high magnification — the behaviour of a two-element crown-and-flint design rather than a fault in this example. On clusters, nebulae and general low-power sweeping, which is the observing an f\/6.5 five-inch is built around, it is not a factor. Observers who want it reduced usually add a minus-violet filter to the 2-inch diagonal, and we stock those; observers who want the colour gone rather than reduced are looking at an ED or apochromatic triplet, which we also carry.\u003c\/p\u003e\n\u003ch3\u003e\u003cstrong\u003eRecommended Uses\u003c\/strong\u003e\u003c\/h3\u003e\n\u003cul\u003e\n\u003cli\u003eLow and medium-power sweeping of open clusters, bright nebulae and the larger galaxies.\u003c\/li\u003e\n\u003cli\u003eLunar and planetary observing on steady nights, within the published .9 arcsec resolution.\u003c\/li\u003e\n\u003cli\u003eDouble-star work, where the resolution figure is the governing specification.\u003c\/li\u003e\n\u003cli\u003ePublic outreach, star parties and classroom sessions.\u003c\/li\u003e\n\u003c\/ul\u003e\n\n\u003ch3\u003e\u003cstrong\u003eCompatibility and Accessory Notes\u003c\/strong\u003e\u003c\/h3\u003e\n\u003cul\u003e\n\u003cli\u003e\n\u003cstrong\u003eMount:\u003c\/strong\u003e not included. The published tube weight is 15.6lb before the diagonal, finder and an eyepiece, so the loaded assembly sits above that. A mount rated comfortably beyond the loaded figure is the sensible starting point for visual use, and more again for imaging.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eDovetail:\u003c\/strong\u003e the Vixen-style universal plate on the cradle rings drops into Vixen saddles and into dual-fit saddles that take both Vixen and Losmandy plates.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eEyepieces:\u003c\/strong\u003e none supplied. The 2-inch focuser and diagonal accept 2-inch eyepieces directly and 1.25-inch eyepieces through the included compression-ring adapter. At 826mm, a 30mm gives 27.5x, a 25mm gives 33x, a 9mm gives 92x and a 5.5mm gives 150x.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eImaging:\u003c\/strong\u003e a field flattener is the usual addition for deep-sky work with a fast refractor. Explore Scientific does not publish a corrected image circle or a backfocus figure for this tube, so we are not quoting one — send us the camera and flattener you have in mind and we will work out the spacing with you.\u003c\/li\u003e\n\u003c\/ul\u003e\n\n\u003ch3\u003e\u003cstrong\u003eGood to Know Before You Order\u003c\/strong\u003e\u003c\/h3\u003e\n\u003cul\u003e\n\u003cli\u003e\n\u003cstrong\u003eThis is an optical tube assembly rather than a complete telescope.\u003c\/strong\u003e A mount, a tripod and at least one eyepiece complete it. We can quote the whole package together if that is simpler.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eIt is a 34-inch, 15.6lb tube.\u003c\/strong\u003e That is a two-hands lift onto a saddle and a real presence in a car boot. Levelling and balancing the mount before the tube goes on makes the job easier.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eAchromatic, not apochromatic.\u003c\/strong\u003e Colour on the brightest objects at high power comes with the design at this focal ratio. A minus-violet filter reduces it, and at the low and medium powers this tube is built for it is not the limiting factor.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eExplore Scientific publishes no corrected image circle and no backfocus figure\u003c\/strong\u003e for the AR127, so those rows are absent from the specification table rather than estimated. If you are planning an imaging train, tell us what is in it and we will sort the spacing out with you.\u003c\/li\u003e\n\u003c\/ul\u003e\n\n\u003ch3\u003e\u003cstrong\u003eFrequently Asked Questions\u003c\/strong\u003e\u003c\/h3\u003e\n\u003cp\u003e\u003cstrong\u003eIs it difficult to set up?\u003c\/strong\u003e\u003c\/p\u003e\n\u003cp\u003eThe optics are the easy part — a refractor arrives collimated and stays that way, so the telescope is ready the moment it is on the mount. The effort is in the handling: 15.6lb and 34 inches is a two-handed lift, and the cradle rings slide onto a Vixen saddle in one motion once the mount is levelled.\u003c\/p\u003e\n\u003cp\u003e\u003cstrong\u003eWhat mount does it need?\u003c\/strong\u003e\u003c\/p\u003e\n\u003cp\u003eOne rated well beyond the loaded tube weight. 15.6lb bare becomes noticeably more with the 2-inch diagonal, the 8x50 finder and a heavy eyepiece hanging off the back. Tell us what you already own and we will give you a straight answer on whether it will carry this comfortably.\u003c\/p\u003e\n\u003cp\u003e\u003cstrong\u003eDoes it come with eyepieces?\u003c\/strong\u003e\u003c\/p\u003e\n\u003cp\u003eNo. The 2-inch dual-speed focuser, the 2-inch dielectric diagonal, the 1.25-inch adapter, the 8x50 finder and the cradle rings are all included; eyepieces are chosen to suit the observing you do.\u003c\/p\u003e\n\u003cp\u003e\u003cstrong\u003eWill I see colour fringing?\u003c\/strong\u003e\u003c\/p\u003e\n\u003cp\u003eOn Venus, Jupiter, Sirius and the edge of the Moon at high magnification, yes. That is what an f\/6.5 achromatic doublet does. On clusters, nebulae and galaxies at the powers this focal ratio was designed around, it is not something that intrudes.\u003c\/p\u003e\n\n\u003ch3\u003e\u003cstrong\u003eBottom Line\u003c\/strong\u003e\u003c\/h3\u003e\n\u003cp\u003eIn short: a 127mm f\/6.5 air-spaced achromat at 826mm focal length, supplied as a 15.6lb tube assembly with a 2-inch dual-speed focuser, a dielectric diagonal, an 8x50 finder and a Vixen-style dovetail — five inches of low-maintenance aperture built for wide, bright views. If you are matching it to a mount you already have, send us the model and we will confirm the fit with you before anything ships.\u003c\/p\u003e","brand":"Explore Scientific","offers":[{"title":"Default Title","offer_id":44012381995119,"sku":"DAR127065-02","price":1057.95,"currency_code":"CAD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0686\/0049\/6239\/files\/ar_12711__65320.png?v=1766547929"},{"product_id":"explore-scientific-es-ed0806-01","title":"Explore Scientific ED80 Essential Series 80mm f\/6 Air-Spaced Triplet APO Refractor Telescope","description":"\u003ch3\u003e\u003cstrong\u003eProduct Overview\u003c\/strong\u003e\u003c\/h3\u003e\n\u003cp\u003eThe Explore Scientific ED80 Essential Series is an 80mm air-spaced triplet apochromatic refractor with a focal length of 480mm at f\/6. The objective uses HOYA FCD1 extra-low-dispersion glass with EMD multi-layer coatings. Explore Scientific publishes a limiting magnitude of 12 and a resolution of 1.45 arcsec for it, over an 85mm tube diameter, at 5.95 lb (2.7 kg) — a genuinely portable weight for a triplet apochromat.\u003c\/p\u003e\n\u003cp\u003eThe tube measures 18.5″ (475mm) with the dew shield extended and 15″ (381mm) with it retracted, which puts it comfortably inside a carry-on-sized case. It comes with a 2-inch rack-and-pinion focuser with extension tubes, a pre-installed Hybrid Finder Scope Base and a Vixen-style dovetail, so the tube is ready to mount and use without further hardware.\u003c\/p\u003e\n\n\u003ch3\u003e\u003cstrong\u003eWho It's For\u003c\/strong\u003e\u003c\/h3\u003e\n\u003cul\u003e\n\u003cli\u003e\n\u003cstrong\u003eWide-field deep-sky imagers:\u003c\/strong\u003e 480mm at f\/6 frames large nebulae, the Andromeda region and big open clusters as whole objects, and a fast focal ratio keeps exposures short.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eTravellers and observers short on space:\u003c\/strong\u003e 5.95 lb and a 15-inch retracted tube go in hand luggage, in a backpack or on a small mount without argument.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eImagers running a larger main telescope\u003c\/strong\u003e who want a well-corrected secondary or guide instrument that also works as a standalone scope.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eVisual observers who value grab-and-go:\u003c\/strong\u003e this is a good match if the telescope you actually use is the one that gets outside in five minutes rather than the one that needs a plan.\u003c\/li\u003e\n\u003c\/ul\u003e\n\n\u003ch3\u003e\u003cstrong\u003eKey Features \u0026amp; Design\u003c\/strong\u003e\u003c\/h3\u003e\n\u003cul\u003e\n\u003cli\u003e\n\u003cstrong\u003e80mm air-spaced triplet objective:\u003c\/strong\u003e three elements with air gaps rather than cement, in an apochromatic configuration.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eHOYA FCD1 extra-low-dispersion glass:\u003c\/strong\u003e the low-dispersion element that pulls the design's colour correction into apochromatic territory.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003e480mm focal length at f\/6:\u003c\/strong\u003e fast enough for wide-field imaging and short enough to keep the tube compact.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003e2-inch rack-and-pinion focuser with extension tubes:\u003c\/strong\u003e a positive, direct-drive focuser mechanism, with the extension tubes needed to reach focus with a diagonal or a camera.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eHybrid Finder Scope Base pre-installed:\u003c\/strong\u003e accepts finder shoes of both common patterns without changing the base.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eVixen-style dovetail\u003c\/strong\u003e for mounting on any Vixen saddle or dual-format saddle.\u003c\/li\u003e\n\u003c\/ul\u003e\n\n\u003ch3\u003e\u003cstrong\u003eOptical Design\u003c\/strong\u003e\u003c\/h3\u003e\n\u003cp\u003eAn achromatic doublet brings two wavelengths to a common focus and leaves a residual — the secondary spectrum — visible as colour around bright objects. An apochromatic triplet adds a third element, and with one of the three made from extra-low-dispersion glass, the designer can bring three widely separated wavelengths to essentially the same plane. What that means at the eyepiece is that violet and deep red land close enough to the visual focus that colour fringing stops being a feature of the view, and at the sensor it means bright stars record as points rather than as blue-haloed blobs.\u003c\/p\u003e\n\u003cp\u003eHOYA FCD1 is the ED glass in this objective. Its role is dispersion control: it separates the wavelengths less than ordinary crown or flint glass does, leaving the mating elements a smaller residual to correct. Air spacing rather than cementing gives the design six air-glass surfaces to shape instead of four, and removes a cement layer as a thermal variable during cool-down.\u003c\/p\u003e\n\u003cp\u003eAt f\/6 the light cone is fast, which is what makes this a short-exposure instrument for imaging. It also means the field curvature inherent to a refractor objective shows up sooner across a large sensor, which is why wide-field imagers pair a scope like this with a field flattener — and why many use a reducer-flattener to go faster still. Explore Scientific does not publish a corrected image circle or a backfocus distance for this tube, so those rows are absent below rather than estimated. Tell us which camera and flattener you are planning around and we will work the spacing through with you.\u003c\/p\u003e\n\n\u003ch3\u003e\u003cstrong\u003eRecommended Uses\u003c\/strong\u003e\u003c\/h3\u003e\n\u003cul\u003e\n\u003cli\u003eWide-field deep-sky astrophotography on a tracking equatorial mount, with a flattener matched to the sensor.\u003c\/li\u003e\n\u003cli\u003eGrab-and-go visual observing — open clusters, large nebulae, the Milky Way, comets and the Moon.\u003c\/li\u003e\n\u003cli\u003eTravel astronomy, where 5.95 lb and a 15-inch retracted tube fit the luggage allowance.\u003c\/li\u003e\n\u003c\/ul\u003e\n\n\u003ch3\u003e\u003cstrong\u003eCompatibility and Accessory Notes\u003c\/strong\u003e\u003c\/h3\u003e\n\u003cul\u003e\n\u003cli\u003e\n\u003cstrong\u003eMount:\u003c\/strong\u003e not included. At 5.95 lb bare, this tube sits within the capacity of most small equatorial and alt-azimuth mounts — though for imaging, tracking accuracy rather than raw capacity is what governs the choice. Tell us how you plan to use it and we will suggest something appropriate.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eDovetail:\u003c\/strong\u003e the Vixen-style plate seats in any Vixen saddle, and in the dual-format saddles that accept both Vixen and Losmandy plates.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eFocuser:\u003c\/strong\u003e 2-inch rack and pinion with extension tubes supplied, so it takes 2-inch accessories directly and 1.25-inch ones with an adapter.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eEyepieces and diagonal:\u003c\/strong\u003e not listed in the published package. At 480mm, a 30mm eyepiece gives 16x, a 20mm gives 24x, and a 9mm gives 53x — we can put together a set that covers the range.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eField flattener:\u003c\/strong\u003e a separate purchase, as it is with any fast refractor used for wide-field imaging. We stock flatteners and reducer-flatteners and can match one to your camera.\u003c\/li\u003e\n\u003c\/ul\u003e\n\n\u003ch3\u003e\u003cstrong\u003eGood to Know Before You Order\u003c\/strong\u003e\u003c\/h3\u003e\n\u003cul\u003e\n\u003cli\u003e\n\u003cstrong\u003eThis is an optical tube assembly, not a complete telescope.\u003c\/strong\u003e A mount, tripod, diagonal and at least one eyepiece are separate. We assemble packages around this tube regularly — tell us how you intend to use it and we will price the whole setup.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eEighty millimetres is eighty millimetres.\u003c\/strong\u003e The published 1.45 arcsec resolution and magnitude 12 limit are what the aperture supports. This telescope excels at wide, well-corrected fields rather than at maximum-power planetary detail, and that is what the f\/6 design is built around.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eA field flattener is a separate item for wide-field imaging.\u003c\/strong\u003e Without one, stars toward the corners of a large sensor will show the field curvature every refractor objective produces. We can match a flattener to your camera's sensor size.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eNo corrected image circle or backfocus figure is published\u003c\/strong\u003e for this tube, so we quote neither. Send us your imaging train and we will work out what we can establish about the spacing.\u003c\/li\u003e\n\u003c\/ul\u003e\n\n\u003ch3\u003e\u003cstrong\u003eFrequently Asked Questions\u003c\/strong\u003e\u003c\/h3\u003e\n\u003cp\u003e\u003cstrong\u003eIs it difficult to set up?\u003c\/strong\u003e\u003c\/p\u003e\n\u003cp\u003eVery little to it. A refractor needs no collimation, so the optics are ready as soon as the tube is on the mount, and at 5.95 lb it is a comfortable one-handed lift. The dovetail slides into a Vixen saddle and locks, the finder goes on the pre-installed base, and the focuser takes the diagonal and eyepiece directly. Most people are observing within a few minutes of carrying it outside.\u003c\/p\u003e\n\u003cp\u003e\u003cstrong\u003eWhat mount does it need?\u003c\/strong\u003e\u003c\/p\u003e\n\u003cp\u003eFor visual use, most small equatorial and alt-azimuth mounts will carry 5.95 lb comfortably. For deep-sky imaging the requirement is tracking accuracy rather than capacity, so a tracking equatorial mount is the starting point. Tell us what you have or what you are considering and we will give you an honest assessment.\u003c\/p\u003e\n\u003cp\u003e\u003cstrong\u003eDoes it come with eyepieces or a diagonal?\u003c\/strong\u003e\u003c\/p\u003e\n\u003cp\u003eNeither is listed in the published package. The tube arrives with its 2-inch rack-and-pinion focuser, extension tubes, pre-installed Hybrid Finder Scope Base and Vixen dovetail. We can supply a diagonal and a starting eyepiece set alongside it.\u003c\/p\u003e\n\u003cp\u003e\u003cstrong\u003eWill I see false colour?\u003c\/strong\u003e\u003c\/p\u003e\n\u003cp\u003eAn air-spaced triplet on FCD1 ED glass is built to remove it. On the very brightest targets at high power, some residual is inherent to every refracting design, but it is not the limiting factor in this telescope the way it would be in an achromat.\u003c\/p\u003e\n\n\u003ch3\u003e\u003cstrong\u003eBottom Line\u003c\/strong\u003e\u003c\/h3\u003e\n\u003cp\u003eIn short: an 80mm f\/6 air-spaced triplet apochromat on HOYA FCD1 ED glass, 480mm focal length, 5.95 lb, with a 2-inch rack-and-pinion focuser, extension tubes, a pre-installed Hybrid finder base and a Vixen dovetail — a wide-field imaging and grab-and-go visual instrument that travels easily and needs nothing from you between sessions. If you are matching it to a mount or planning a flattener and camera behind it, send us the details and we will work through the fit with you.\u003c\/p\u003e","brand":"Explore Scientific","offers":[{"title":"Default Title","offer_id":44012382290031,"sku":"ES-ED0806-02","price":986.95,"currency_code":"CAD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0686\/0049\/6239\/files\/ed80_header_281_29__48199.jpg?v=1766547935"},{"product_id":"explore-scientific-ed102","title":"Explore Scientific ED102 Essential Series 102mm f\/7 Air-Spaced Triplet APO Refractor Telescope","description":"\u003ch3\u003e\u003cstrong\u003eProduct Overview\u003c\/strong\u003e\u003c\/h3\u003e\n\u003cp\u003eThe Explore Scientific ED102 Essential Series is a 102mm air-spaced triplet apochromatic refractor with a focal length of 714mm at f\/7. The centre element is genuine HOYA FCD1 extra-low-dispersion glass, and Explore Scientific applies proprietary multi-layer coatings aimed at holding transmission high while keeping chromatic aberration low. Published figures are a limiting magnitude of 12.5 and a resolution of 1.14 arcsec.\u003c\/p\u003e\n\u003cp\u003eThe tube is 30.5″ (774mm) long with the dew shield extended and 23.75″ (603mm) with it retracted, 119mm in diameter, and weighs 12 lb (5.4 kg). It rides on a Vixen-pattern dovetail and focuses through a precision 2-inch rack-and-pinion focuser supplied with extension tubes. What ships is the telescope tube with its dew shield and the focuser extension tubes — no mount and no eyepieces.\u003c\/p\u003e\n\u003ch3\u003e\u003cstrong\u003eWho It's For\u003c\/strong\u003e\u003c\/h3\u003e\n\u003cul\u003e\n\u003cli\u003e\n\u003cstrong\u003eDeep-sky imagers:\u003c\/strong\u003e 714mm at f\/7 is a widely used astrophotography focal length — large enough for the brighter galaxies and globulars, short enough to frame the big nebulae and to keep guiding demands reasonable.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eVisual observers who want colour-free views:\u003c\/strong\u003e the triplet design with FCD1 ED glass removes the violet halo an achromat leaves on Venus, Jupiter and the lunar limb.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eObservers who travel:\u003c\/strong\u003e this is a good match if you want an apochromat that packs down to 23.75″ with the dew shield retracted and weighs 12 lb.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eOwners of mid-capacity equatorial mounts:\u003c\/strong\u003e this is a good match if your mount is rated comfortably above the loaded weight of a 12 lb tube plus rings, diagonal, finder and camera.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eDouble-star and lunar observers,\u003c\/strong\u003e working near the published 1.14 arcsec resolution.\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003ch3\u003e\u003cstrong\u003eKey Features \u0026amp; Design\u003c\/strong\u003e\u003c\/h3\u003e\n\u003cul\u003e\n\u003cli\u003e\n\u003cstrong\u003e102mm air-spaced triplet:\u003c\/strong\u003e three elements with air gaps between them rather than cemented pairs.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eGenuine HOYA FCD1 ED glass\u003c\/strong\u003e in the centre element, chosen for how closely it brings widely separated wavelengths to a common focus.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003e714mm focal length at f\/7:\u003c\/strong\u003e a balanced focal ratio for both wide-field imaging and medium-to-high power visual work.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eProprietary multi-layer coatings\u003c\/strong\u003e applied to maximise light transmission alongside the colour correction.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003ePrecision 2-inch rack-and-pinion focuser\u003c\/strong\u003e supplied with extension tubes, which is what makes reaching focus with a diagonal or a camera straightforward.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eRetracting dew shield:\u003c\/strong\u003e 30.5″ (774mm) extended, 23.75″ (603mm) retracted.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eVixen-pattern dovetail\u003c\/strong\u003e on a tube 119mm in outside diameter.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003ePublished performance:\u003c\/strong\u003e limiting magnitude 12.5, resolution 1.14 arcsec, weight 12 lb (5.4 kg).\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003ch3\u003e\u003cstrong\u003eOptical Design\u003c\/strong\u003e\u003c\/h3\u003e\n\u003cp\u003eAn achromatic doublet brings two wavelengths to a common focus and leaves the rest slightly out, which shows as a violet halo around bright objects at high power. A triplet apochromat adds a third element so three widely separated wavelengths converge together, and the residual error falls below what the eye picks up in normal use. The glass in the centre element is what makes that practical: extra-low-dispersion types spread the colours less to begin with, so the design has less to correct. HOYA FCD1 is the type used here, and Explore Scientific specifies it as genuine FCD1 rather than an equivalent.\u003c\/p\u003e\n\u003cp\u003eAt f\/7 the light cone is moderate. That has a direct effect on imaging: field curvature and off-axis aberrations are easier to correct than in a fast astrograph, and focus tolerance is looser, which makes a night of unattended imaging less fragile. The 2-inch rack-and-pinion focuser is the mechanical half of that story — rack-and-pinion drives resist slipping under load in a way that a lightly tensioned Crayford does not, which matters when a camera train hangs off the drawtube pointed at the zenith.\u003c\/p\u003e\n\u003cp\u003eExplore Scientific does not publish a corrected image circle or a backfocus distance for this tube, so those rows are absent from the specifications rather than estimated. Send us the camera and flattener you have in mind and we will work out the spacing with you before anything ships.\u003c\/p\u003e\n\u003ch3\u003e\u003cstrong\u003eRecommended Uses\u003c\/strong\u003e\u003c\/h3\u003e\n\u003cul\u003e\n\u003cli\u003eWide-field and medium-field deep-sky astrophotography at 714mm.\u003c\/li\u003e\n\u003cli\u003eVisual observing of the Moon, planets and double stars where colour correction sets the ceiling.\u003c\/li\u003e\n\u003cli\u003eDeep-sky visual work on clusters, nebulae and the brighter galaxies.\u003c\/li\u003e\n\u003cli\u003ePortable dark-site sessions, given the 12 lb weight and 23.75″ retracted length.\u003c\/li\u003e\n\u003cli\u003eSolar observing with an appropriate front-mounted filter, and outreach sessions where a refractor's zero-maintenance optics matter.\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003ch3\u003e\u003cstrong\u003eCompatibility and Accessory Notes\u003c\/strong\u003e\u003c\/h3\u003e\n\u003cul\u003e\n\u003cli\u003e\n\u003cstrong\u003eMount:\u003c\/strong\u003e not included. The published tube weight of 12 lb is before rings, diagonal, finder and camera. For visual use a mount comfortably above that loaded figure works well; for imaging, more headroom again.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eDovetail:\u003c\/strong\u003e Vixen pattern, fitting Vixen saddles and dual-fit saddles.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eEyepieces:\u003c\/strong\u003e not included. At 714mm, a 26mm eyepiece gives 27x, a 20mm gives 36x, a 12mm gives 60x and a 6mm gives 119x.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eDiagonal:\u003c\/strong\u003e the 2-inch focuser takes 2-inch diagonals, and the supplied extension tubes are what bring the focal plane out to meet one. We stock dielectric 2-inch diagonals.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eImaging train:\u003c\/strong\u003e a field flattener is the standard companion for deep-sky work. Since no corrected image circle is published, we will confirm the flattener match against your camera rather than quote a figure.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eFocal extenders:\u003c\/strong\u003e a 2x or 3x extender on 714mm brings lunar and planetary work into a useful magnification range for a 102mm aperture.\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003ch3\u003e\u003cstrong\u003eGood to Know Before You Order\u003c\/strong\u003e\u003c\/h3\u003e\n\u003cul\u003e\n\u003cli\u003e\n\u003cstrong\u003eThis is an optical tube assembly, not a complete telescope.\u003c\/strong\u003e A mount, a tripod and at least one eyepiece are needed alongside it. We can quote the package as a whole if that is simpler — tell us what you already own.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eThe 30.5″ length is with the dew shield extended.\u003c\/strong\u003e Retracted it is 23.75″, which is the figure to measure a case or a vehicle against.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eNo corrected image circle or backfocus figure is published\u003c\/strong\u003e for this tube, so those rows are left out below rather than filled with an estimate. If you are planning an imaging train, send us the camera and flattener and we will work the spacing out with you.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eA triplet takes longer to reach ambient temperature than a doublet of the same aperture.\u003c\/strong\u003e Setting the tube outside ahead of the session is what lets the optics settle before high-power observing begins.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eAt 12 lb it is portable but not featherweight.\u003c\/strong\u003e One person handles it comfortably, and the mount underneath it wants capacity to spare once the diagonal, finder and eyepiece are added. We are glad to check your mount against a loaded figure.\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003ch3\u003e\u003cstrong\u003eFrequently Asked Questions\u003c\/strong\u003e\u003c\/h3\u003e\n\u003cp\u003e\u003cstrong\u003eIs it difficult to set up?\u003c\/strong\u003e\u003c\/p\u003e\n\u003cp\u003eThe optics need nothing — a refractor holds its collimation, so the tube is ready as soon as it is in the rings and on the mount. At 12 lb it is a comfortable one-person lift, and it goes on most easily with the mount levelled and the counterweights roughly positioned first. The extension tubes take a moment to fit for whatever is going in the focuser.\u003c\/p\u003e\n\u003cp\u003e\u003cstrong\u003eWhat mount will carry it?\u003c\/strong\u003e\u003c\/p\u003e\n\u003cp\u003eFor visual use, one rated above the 12 lb tube weight with room for the diagonal, finder and eyepiece on top. For imaging, more margin, since tracking accuracy falls off well before a mount reaches its rated capacity. Tell us the model you own and we will give you a straight answer.\u003c\/p\u003e\n\u003cp\u003e\u003cstrong\u003eDoes it come with eyepieces or a diagonal?\u003c\/strong\u003e\u003c\/p\u003e\n\u003cp\u003eNo. The tube arrives with its dew shield and the focuser extension tubes; the diagonal, eyepieces, finder and rings are chosen separately and we can assemble a set that matches.\u003c\/p\u003e\n\u003cp\u003e\u003cstrong\u003eWill I see colour fringing?\u003c\/strong\u003e\u003c\/p\u003e\n\u003cp\u003eAn air-spaced triplet using HOYA FCD1 ED glass is designed to eliminate it in normal use. On Venus, Sirius and the lunar limb at high power the image stays neutral where a two-element achromat would show violet.\u003c\/p\u003e\n\u003cp\u003e\u003cstrong\u003eCan I image with it?\u003c\/strong\u003e\u003c\/p\u003e\n\u003cp\u003eYes — 714mm at f\/7 is a well-liked deep-sky imaging focal length. A field flattener is the usual addition, along with an equatorial mount and guiding.\u003c\/p\u003e\n\u003cp\u003e\u003cstrong\u003eHow does it compare to the 127mm models?\u003c\/strong\u003e\u003c\/p\u003e\n\u003cp\u003eWe stock three ED127s and they are easy to confuse, so it is worth being precise. All three are 127mm at 952mm and f\/7.5. The \u003cstrong\u003eED127 Essential\u003c\/strong\u003e uses HOYA FCD1 glass — the same type as this ED102 — in an 18 lb tube with a 2-inch two-speed rack-and-pinion focuser. The \u003cstrong\u003eED127 FCD100\u003c\/strong\u003e steps up to HOYA FCD100 glass and a 2.5-inch dual-speed HEX Crayford focuser, also 18 lb in the painted aluminium tube. The \u003cstrong\u003eED127 FCD100 Carbon Fiber\u003c\/strong\u003e pairs those same optics and focuser with a carbon tube at 14 lb, which is the one to look at if your mount is the limiting factor.\u003c\/p\u003e\n\u003cp\u003eAgainst any of them, this ED102 gathers less light and resolves less detail — 127mm is roughly 55% more aperture area — but it is 12 lb rather than 14 or 18, it is shorter, it asks considerably less of a mount, and at 714mm it gives a wider field per eyepiece. When people are choosing between them, the mount they own or plan to buy usually settles it faster than the optics do. Ask us and we will work through it with you.\u003c\/p\u003e\n\u003ch3\u003e\u003cstrong\u003eBottom Line\u003c\/strong\u003e\u003c\/h3\u003e\n\u003cp\u003eIn short: a 102mm f\/7 air-spaced triplet apochromat with genuine HOYA FCD1 ED glass, a 2-inch rack-and-pinion focuser with extension tubes, a Vixen dovetail and a published weight of 12 lb — a 714mm focal length that suits wide-field imaging and high-power visual work equally well. If you are matching it to a mount or planning an imaging train around it, send us the details and we will confirm the fit with you before you order.\u003c\/p\u003e","brand":"Explore Scientific","offers":[{"title":"Default Title","offer_id":44012382453871,"sku":"ES-ED10207-02","price":1409.95,"currency_code":"CAD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0686\/0049\/6239\/files\/ed102straightonsmall21__85958.jpg?v=1766547942"},{"product_id":"explore-scientific-ed-127-075-04","title":"Explore Scientific ED127 Essential Series 127mm f\/7.5 Air-Spaced Triplet APO Refractor Telescope","description":"\u003ch3\u003e\u003cstrong\u003eProduct Overview\u003c\/strong\u003e\u003c\/h3\u003e\n\u003cp\u003eThe Explore Scientific ED127 Essential Series is a 127mm air-spaced triplet apochromatic refractor with a focal length of 952mm at f\/7.5. The objective uses genuine HOYA FCD1 extra-low-dispersion glass with EMD enhanced multi-layer coatings on every optical surface. Explore Scientific publishes a limiting magnitude of 13 and a resolution of 0.9 arcsec — five inches of well-corrected aperture, which is where a refractor starts to hold its own against much larger reflectors on planetary and double-star work.\u003c\/p\u003e\n\u003cp\u003eThis is the fourth-generation tube, and the changes are worth knowing about. The front cell is a precision design with push-pull tilt and centering adjustment, so the objective can be collimated rather than simply trusted. The focuser is a 2-inch two-speed rack-and-pinion with heavy-duty locks and rotation adjustment. The dew shield retracts, which takes the tube from 41.75″ (1060mm) extended down to 33.25″ (849mm) for transport. Cradle rings with a carry handle, a Vixen-style dovetail, a 2-inch 99% dielectric star diagonal and the Explore Scientific 2N1 finder base all come in the box. The tube alone is 18 lb (8.16 kg); with the rings and diagonal fitted the assembly is closer to 22 lb.\u003c\/p\u003e\n\n\u003ch3\u003e\u003cstrong\u003eWho It's For\u003c\/strong\u003e\u003c\/h3\u003e\n\u003cul\u003e\n\u003cli\u003e\n\u003cstrong\u003eAstrophotographers who have outgrown a small refractor:\u003c\/strong\u003e 952mm at f\/7.5 frames galaxies, globulars and planetary nebulae at a scale an 80mm tube cannot reach, while staying short enough to guide without drama.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003ePlanetary and lunar observers:\u003c\/strong\u003e 127mm of unobstructed aperture at 0.9 arcsec resolution delivers the high-contrast, colour-free view that is the reason people buy apochromats in the first place.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eDouble-star observers,\u003c\/strong\u003e working close to the published 0.9 arcsec figure with no diffraction spikes and no central obstruction to fill in the gaps.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eObservers who want one telescope to do everything well:\u003c\/strong\u003e this is a good match if you would rather own a single instrument that images deep-sky, splits doubles and shows the Moon properly than three that each do one job.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eAnyone who has been frustrated by a fixed front cell:\u003c\/strong\u003e the push-pull collimation on this generation means star shape is something you can correct rather than live with.\u003c\/li\u003e\n\u003c\/ul\u003e\n\n\u003ch3\u003e\u003cstrong\u003eKey Features \u0026amp; Design\u003c\/strong\u003e\u003c\/h3\u003e\n\u003cul\u003e\n\u003cli\u003e\n\u003cstrong\u003e127mm air-spaced triplet objective:\u003c\/strong\u003e three elements separated by air rather than cement, in an apochromatic configuration.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eGenuine HOYA FCD1 ED glass:\u003c\/strong\u003e Explore Scientific specifies the actual FCD1 type rather than an unnamed equivalent.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eEMD enhanced multi-layer coatings\u003c\/strong\u003e on all optical surfaces, applied to hold transmission high across the visual band.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003ePrecision front cell with push-pull adjustment\u003c\/strong\u003e for tilt and centering — the objective can be collimated for the tightest possible stars.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003e2-inch two-speed rack-and-pinion focuser\u003c\/strong\u003e with heavy-duty locks and rotation adjustment, so a camera train can be squared up and then held there.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eRetractable dew shield:\u003c\/strong\u003e 41.75″ (1060mm) extended, 33.25″ (849mm) retracted.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eCradle rings with a slotted carry handle,\u003c\/strong\u003e tapped 1\/4″-20 for piggybacking a DSLR, on a Vixen-style dovetail plate.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003e2-inch 99% dielectric star diagonal included,\u003c\/strong\u003e along with the 2N1 finder scope base (finder scope sold separately).\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003ePublished performance:\u003c\/strong\u003e limiting magnitude 13, resolution 0.9 arcsec, tube diameter 130mm, tube weight 18 lb (8.16 kg).\u003c\/li\u003e\n\u003c\/ul\u003e\n\n\u003ch3\u003e\u003cstrong\u003eOptical Design\u003c\/strong\u003e\u003c\/h3\u003e\n\u003cp\u003eAn achromatic doublet brings two wavelengths to a common focus and leaves a residual — the secondary spectrum — that shows as violet fringing around bright objects. A triplet apochromat adds a third element so that three widely separated wavelengths converge together, and with one element made from extra-low-dispersion glass the residual drops below what the eye registers in normal use. At 127mm this matters more than it does at 80mm: the brighter the image and the higher the usable magnification, the more obvious an uncorrected secondary spectrum becomes. HOYA FCD1 is the ED type used here, and air spacing gives the designer six air-glass surfaces to shape rather than four, while removing a cement layer as a variable during cool-down.\u003c\/p\u003e\n\u003cp\u003eAt f\/7.5 the light cone is moderate rather than fast. For imaging that means field curvature and off-axis aberration are easier to correct than in a fast astrograph, and focus tolerance is looser — which makes an unattended night of subframes considerably less fragile. It also means longer exposures than an f\/5 or f\/6 instrument would need for the same signal, which is the trade you make for the extra focal length and resolution.\u003c\/p\u003e\n\u003cp\u003eThe two-speed rack-and-pinion focuser is the mechanical half of the story. A rack-and-pinion drive resists slipping under a heavy imaging train in a way a lightly tensioned Crayford does not, and that matters when a camera, filter wheel and flattener hang off the drawtube pointed near the zenith. The 10:1 fine adjustment is what makes critical focus at 952mm a matter of a small deliberate movement rather than a hunt.\u003c\/p\u003e\n\u003cp\u003eExplore Scientific does not publish a corrected image circle or a backfocus distance for this tube, so we quote neither rather than estimate. Tell us which camera and flattener you are planning around and we will work the spacing through with you before anything ships.\u003c\/p\u003e\n\n\u003ch3\u003e\u003cstrong\u003eRecommended Uses\u003c\/strong\u003e\u003c\/h3\u003e\n\u003cul\u003e\n\u003cli\u003eDeep-sky astrophotography at 952mm — galaxies, globular clusters and planetary nebulae — on a tracking equatorial mount with a flattener matched to the sensor.\u003c\/li\u003e\n\u003cli\u003eHigh-power visual observing of the Moon, planets and double stars, where colour correction and unobstructed aperture set the ceiling.\u003c\/li\u003e\n\u003cli\u003eDeep-sky visual work on clusters, nebulae and brighter galaxies.\u003c\/li\u003e\n\u003cli\u003eSolar observing with an appropriate front-mounted filter, and outreach sessions where a refractor's zero-maintenance optics matter.\u003c\/li\u003e\n\u003c\/ul\u003e\n\n\u003ch3\u003e\u003cstrong\u003eCompatibility and Accessory Notes\u003c\/strong\u003e\u003c\/h3\u003e\n\u003cul\u003e\n\u003cli\u003e\n\u003cstrong\u003eMount:\u003c\/strong\u003e not included, and this is the part to plan carefully. The tube is 18 lb bare and roughly 22 lb with rings and diagonal, before a finder, eyepiece or camera. At 952mm the mount also has to track well, not just carry the load — for imaging we would want meaningful headroom over the loaded weight. Tell us what you own or are considering and we will give you a straight assessment.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eDovetail:\u003c\/strong\u003e Vixen-style plate on the cradle rings, seating in any Vixen saddle or dual-format saddle. On a heavier mount, a Losmandy-style plate is a common upgrade for the extra rigidity.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eFocuser:\u003c\/strong\u003e 2-inch two-speed rack and pinion, taking 2-inch accessories directly and 1.25-inch ones with an adapter.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eDiagonal:\u003c\/strong\u003e a 2-inch 99% dielectric star diagonal is included, so the tube is ready for visual use as soon as you add an eyepiece.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eEyepieces:\u003c\/strong\u003e not included. At 952mm, a 30mm eyepiece gives 32x, a 20mm gives 48x, a 12mm gives 79x and a 6mm gives 159x — we can put together a set that covers the range.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eFinder:\u003c\/strong\u003e the 2N1 base is pre-installed and accepts both common finder shoe patterns; the finder scope itself is a separate purchase.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eField flattener:\u003c\/strong\u003e a separate item for deep-sky imaging, as it is with any refractor. Since no corrected image circle is published, we will confirm the flattener match against your camera rather than quote a figure.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eFocal extenders:\u003c\/strong\u003e a 2x or 3x extender on 952mm brings lunar and planetary work into a genuinely useful magnification range for a 127mm aperture.\u003c\/li\u003e\n\u003c\/ul\u003e\n\n\u003ch3\u003e\u003cstrong\u003eGood to Know Before You Order\u003c\/strong\u003e\u003c\/h3\u003e\n\u003cul\u003e\n\u003cli\u003e\n\u003cstrong\u003eThis is an optical tube assembly, not a complete telescope.\u003c\/strong\u003e A mount, a tripod and at least one eyepiece are separate. We assemble packages around this tube regularly — tell us how you intend to use it and we will price the whole setup.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eThe mount is the real decision here.\u003c\/strong\u003e An 18 lb tube at 952mm asks more of a mount than the raw weight suggests, particularly for imaging. This is the single most common place people underspend, and we would rather talk it through with you first.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eThe 41.75″ length is with the dew shield extended.\u003c\/strong\u003e Retracted it is 33.25″, which is the figure to measure a case or a vehicle against.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eA five-inch triplet takes real time to reach ambient temperature.\u003c\/strong\u003e More glass means a longer cool-down than a doublet or a smaller triplet — setting the tube outside well ahead of the session is what lets the optics settle before high-power observing begins.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eNo corrected image circle or backfocus figure is published\u003c\/strong\u003e for this tube, so we quote neither. Send us your imaging train and we will work out what we can establish about the spacing.\u003c\/li\u003e\n\u003c\/ul\u003e\n\n\u003ch3\u003e\u003cstrong\u003eFrequently Asked Questions\u003c\/strong\u003e\u003c\/h3\u003e\n\u003cp\u003e\u003cstrong\u003eIs it difficult to set up?\u003c\/strong\u003e\u003c\/p\u003e\n\u003cp\u003eThe optics need nothing routine — a refractor holds its collimation through normal use, and the push-pull front cell is there for correction rather than regular adjustment. At 18 lb the tube is a manageable one-person lift, and the carry handle on the rings is genuinely useful for that. Level the mount and position the counterweights first, then the dovetail slides into the saddle and locks. The diagonal and eyepiece go straight into the focuser.\u003c\/p\u003e\n\u003cp\u003e\u003cstrong\u003eWhat mount does it need?\u003c\/strong\u003e\u003c\/p\u003e\n\u003cp\u003eFor visual use, a mount comfortably above the roughly 22 lb loaded weight of tube, rings and diagonal. For deep-sky imaging at 952mm, more margin again — tracking accuracy falls away well before a mount reaches its rated capacity. Tell us the model you have in mind and we will tell you honestly whether it is enough.\u003c\/p\u003e\n\u003cp\u003e\u003cstrong\u003eDoes it come with a diagonal or eyepieces?\u003c\/strong\u003e\u003c\/p\u003e\n\u003cp\u003eA 2-inch 99% dielectric star diagonal is included, along with the cradle rings, dew shield, Vixen dovetail and 2N1 finder base. Eyepieces and the finder scope itself are separate, and we can supply a set that suits how you plan to use it.\u003c\/p\u003e\n\u003cp\u003e\u003cstrong\u003eWill I see false colour?\u003c\/strong\u003e\u003c\/p\u003e\n\u003cp\u003eAn air-spaced triplet on genuine HOYA FCD1 ED glass is built to remove it. On Venus, Sirius and the lunar limb at high power the image stays neutral where a two-element achromat of this aperture would show obvious violet.\u003c\/p\u003e\n\u003cp\u003e\u003cstrong\u003eCan I collimate it myself?\u003c\/strong\u003e\u003c\/p\u003e\n\u003cp\u003eYes — that is what the push-pull front cell on this generation is for. It is not something the telescope should need often, but if star shape drifts after travel, the adjustment is there rather than requiring a trip back to the manufacturer. Ask us before you start if you have not done it before.\u003c\/p\u003e\n\u003cp\u003e\u003cstrong\u003eHow does it compare to the ED102 Essential?\u003c\/strong\u003e\u003c\/p\u003e\n\u003cp\u003eThe ED102 is 102mm at 714mm and f\/7, 12 lb, with a single-speed 2-inch rack-and-pinion. The ED127 is 127mm at 952mm and f\/7.5, 18 lb, with a two-speed focuser, push-pull front cell and a diagonal included. The ED127 gathers roughly 55% more light and resolves finer detail; the ED102 is lighter, shorter, asks less of a mount and gives a wider field per eyepiece.\u003c\/p\u003e\n\n\u003ch3\u003e\u003cstrong\u003eBottom Line\u003c\/strong\u003e\u003c\/h3\u003e\n\u003cp\u003eIn short: a 127mm f\/7.5 air-spaced triplet apochromat on genuine HOYA FCD1 ED glass, 952mm focal length, 18 lb, with a precision push-pull front cell, a 2-inch two-speed rack-and-pinion focuser, a retracting dew shield, cradle rings with a piggyback handle, a Vixen dovetail and a 2-inch dielectric diagonal in the box — a five-inch apochromat that images deep-sky properly and shows the Moon and planets the way an unobstructed aperture should. The mount underneath it is the decision that matters most; send us the details and we will work through the fit with you.\u003c\/p\u003e","brand":"Explore Scientific","offers":[{"title":"Default Title","offer_id":44012382781551,"sku":"ES-ED127075-04","price":2114.95,"currency_code":"CAD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0686\/0049\/6239\/files\/ed127_header__23128.jpg?v=1766547948"},{"product_id":"explore-scientific-152mm-carbon-fiber-apo-with-2-hex-focuser","title":"Explore Scientific ED152 152mm f\/8 Carbon Fiber Air-Spaced Triplet APO Telescope","description":"\u003ch3\u003e\u003cstrong\u003eProduct Overview\u003c\/strong\u003e\u003c\/h3\u003e\n\u003cp\u003eThe Explore Scientific ED152 Carbon Fiber is a 152mm air-spaced apochromatic triplet refractor with a focal length of 1216mm at f\/8, built around HOYA FCD1 extra-low dispersion glass in a carbon fibre tube. Explore Scientific publishes a limiting magnitude of 13 and a resolution of .75 arcsec for the optic, with a stated tube weight of 20.5lb; 9.3kg.\u003c\/p\u003e\n\u003cp\u003eThe tube measures 41″ (1041mm) with the dew shield retracted and 52″ (1320mm) extended. It is supplied as an optical tube assembly with a 2.5-inch hexagonal HEX focuser, cradle rings, a finder base and a 99% reflective 2-inch diagonal. A mount and eyepieces are chosen separately.\u003c\/p\u003e\n\u003cp\u003eUnusually, Explore Scientific publishes a complete set of image circle figures for this tube — 50.8mm natively, 76mm with the 3-inch adapter, and separate full-illumination and distortion-free numbers for the flat field adapter and the 0.7 focal reducer. Those figures are reproduced verbatim in the specifications below.\u003c\/p\u003e\n\n\u003ch3\u003e\u003cstrong\u003eWho It's For\u003c\/strong\u003e\u003c\/h3\u003e\n\u003cul\u003e\n\u003cli\u003e\n\u003cstrong\u003eDeep-sky imagers working at medium focal length:\u003c\/strong\u003e 1216mm with a 50.8mm total image circle, rising to 76mm with the 3-inch adapter, covers sensor formats up to and past full frame — the full-frame diagonal is 43.3mm.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eImagers who want a shorter focal length on the same optic:\u003c\/strong\u003e the 0.7 focal reducer takes 1216mm to 851.2mm at f\/5.6.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eHigh-resolution visual observers:\u003c\/strong\u003e .75 arcsec of stated resolution at f\/8 suits lunar, planetary and double-star work as much as imaging.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eObservers carrying gear to dark sites:\u003c\/strong\u003e the carbon fibre tube is what holds a six-inch triplet to a published 20.5lb; 9.3kg.\u003c\/li\u003e\n\u003cli\u003eThis is a good match if you already own an equatorial mount with real capacity in reserve and a Losmandy-pattern saddle.\u003c\/li\u003e\n\u003c\/ul\u003e\n\n\u003ch3\u003e\u003cstrong\u003eKey Features \u0026amp; Design\u003c\/strong\u003e\u003c\/h3\u003e\n\u003cul\u003e\n\u003cli\u003e\n\u003cstrong\u003e152mm air-spaced apochromatic triplet:\u003c\/strong\u003e three elements with air gaps between them, using HOYA FCD1 extra-low dispersion glass.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003e1216mm focal length at f\/8:\u003c\/strong\u003e a long-focus ratio for an apochromat, which eases correction across the field and raises image scale.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eCarbon fibre tube:\u003c\/strong\u003e carbon has a very low coefficient of thermal expansion along the fibre direction, so focus position drifts less across a night than it does in an aluminium tube of the same length.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003e2.5-inch HEX focuser:\u003c\/strong\u003e the hexagonal drawtube resists rotation and flexure that a round drawtube resists only through its pinion and bearings — which matters when a heavy camera train hangs off the back.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eLosmandy dovetail:\u003c\/strong\u003e the wide D-plate pattern, spreading a 20.5lb tube across a long saddle contact.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003e52″ (1320mm) extended, 41″ (1041mm) retracted:\u003c\/strong\u003e the dew shield accounts for 11 inches of the overall length, and published limiting magnitude is 13 with .75 arcsec of resolution.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eSupplied accessories:\u003c\/strong\u003e cradle rings, a finder base and a 99% reflective 2-inch diagonal.\u003c\/li\u003e\n\u003c\/ul\u003e\n\n\u003ch3\u003e\u003cstrong\u003eOptical Design\u003c\/strong\u003e\u003c\/h3\u003e\n\u003cp\u003eAn apochromatic triplet brings three wavelengths to a common focus rather than the two an achromatic doublet manages. The extra element, and the extra-low dispersion glass in the stack, is what removes the violet halo a two-element crown-and-flint design leaves around Venus, Sirius and the lunar limb. In imaging terms, red, green and blue channels focus at very nearly the same point, so stars stay tight in all three rather than bloating in one. Air spacing gives the designer six optical surfaces to shape instead of the four a cemented pair offers, and removes the cement layer as a thermal variable in a 152mm lens.\u003c\/p\u003e\n\u003cp\u003eThe published image circle figures describe what the optic delivers to a sensor. The 50.8mm total image circle is the illuminated field the native 2.5-inch train passes, rising to 76mm with the 3-inch adapter. Explore Scientific separates that from the fully illuminated field (36mm with the flat field adapter) and the distortion-free field (40.4mm with the same adapter). With the 0.7 reducer, full illumination is 20.9mm through the 2-inch version and 30.3mm through the 3-inch, with a 46.4mm distortion-free circle either way — so the choice between reducer paths is a question of sensor size. At f\/8 exposures run longer than on a fast astrograph; what the focal ratio buys back is the image scale 1216mm gives.\u003c\/p\u003e\n\n\u003ch3\u003e\u003cstrong\u003eRecommended Uses\u003c\/strong\u003e\u003c\/h3\u003e\n\u003cul\u003e\n\u003cli\u003eLong-exposure deep-sky imaging of galaxies, globular clusters and compact nebulae at 1216mm, or 851.2mm with the 0.7 reducer.\u003c\/li\u003e\n\u003cli\u003eHigh-resolution lunar and planetary imaging, where .75 arcsec of stated resolution sets the ceiling.\u003c\/li\u003e\n\u003cli\u003eVisual double-star and planetary observing — a 9mm eyepiece gives 135x, a 5mm gives 243x, a 30mm yields 40.5x for low-power sweeping.\u003c\/li\u003e\n\u003cli\u003eNarrowband imaging from suburban skies, where a long focal ratio and a well corrected field work together.\u003c\/li\u003e\n\u003c\/ul\u003e\n\n\u003ch3\u003e\u003cstrong\u003eCompatibility and Accessory Notes\u003c\/strong\u003e\u003c\/h3\u003e\n\u003cul\u003e\n\u003cli\u003e\n\u003cstrong\u003eMount:\u003c\/strong\u003e not included. The tube alone is 20.5lb; 9.3kg before rings, diagonal, finder, camera and filter wheel, so a German equatorial with substantial rated capacity above that is the sensible starting point for imaging.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eDovetail:\u003c\/strong\u003e Losmandy pattern. Saddles that accept both Losmandy and Vixen plates will take it directly; a Vixen-only saddle needs a plate change.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eImaging train:\u003c\/strong\u003e the flat field adapter and the 0.7 focal reducer each have their own published circles, listed in the specifications. Sensor diagonal is the number to compare them against.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eEyepieces and finder:\u003c\/strong\u003e none supplied, though the 99% reflective 2-inch diagonal and a finder base are. The diagonal takes 2-inch eyepieces directly and 1.25-inch eyepieces through an adapter, and accepts 2-inch threaded filters for visual work.\u003c\/li\u003e\n\u003c\/ul\u003e\n\n\u003ch3\u003e\u003cstrong\u003eGood to Know Before You Order\u003c\/strong\u003e\u003c\/h3\u003e\n\u003cul\u003e\n\u003cli\u003e\n\u003cstrong\u003eThis is an optical tube assembly.\u003c\/strong\u003e A mount, a tripod or pier, and eyepieces or a camera complete it. We put packages together regularly — tell us what you already own and we will fill in the gaps.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eIt is a 52-inch tube with the dew shield out,\u003c\/strong\u003e and 41″ retracted. That governs case choice, vehicle space and clearance past the tripod legs. The 20.5lb; 9.3kg figure is the bare tube, so mount capacity is best judged against the loaded weight rather than the published one.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eExplore Scientific does not publish a backfocus distance for this focuser,\u003c\/strong\u003e so that row is absent from the specifications rather than estimated. Send us the camera, filter wheel and adapters you plan to use and we will work the spacing out with you.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eCool-down is real on a 152mm triplet.\u003c\/strong\u003e A large glass stack takes time to reach ambient temperature, and images taken during that period will not show what the optic can do. This is normal for the aperture rather than a fault, and it is the reason many owners set up early.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eThe 0.7 reducer and flat field adapter are separate items,\u003c\/strong\u003e with their published image circles listed below. We stock the adapters and can advise which path suits your sensor.\u003c\/li\u003e\n\u003c\/ul\u003e\n\n\u003ch3\u003e\u003cstrong\u003eFrequently Asked Questions\u003c\/strong\u003e\u003c\/h3\u003e\n\u003cp\u003e\u003cstrong\u003eIs it difficult to set up?\u003c\/strong\u003e\u003c\/p\u003e\n\u003cp\u003eThe optics need no collimation and no maintenance, so the telescope side is simple. The work is mechanical: lifting a 20.5lb, 41-inch tube onto a saddle is a two-hands job, and it goes more easily with the mount levelled and the counterweights already on the shaft.\u003c\/p\u003e\n\u003cp\u003e\u003cstrong\u003eWhat sensor size will it cover?\u003c\/strong\u003e\u003c\/p\u003e\n\u003cp\u003eExplore Scientific publishes 50.8mm of total image circle natively and 76mm with the 3-inch adapter, with 36mm of full illumination through the flat field adapter. A full-frame sensor has a 43.3mm diagonal, so the numbers to compare are in the table.\u003c\/p\u003e\n\u003cp\u003e\u003cstrong\u003eWhat does the 0.7 focal reducer change?\u003c\/strong\u003e\u003c\/p\u003e\n\u003cp\u003eIt takes 1216mm to 851.2mm and f\/8 to f\/5.6, which shortens exposures and widens the field. Full illumination is 20.9mm through the 2-inch version and 30.3mm through the 3-inch, with a 46.4mm distortion-free circle either way.\u003c\/p\u003e\n\u003cp\u003e\u003cstrong\u003eWhat mount does it want?\u003c\/strong\u003e\u003c\/p\u003e\n\u003cp\u003eOne rated comfortably above the loaded weight, with a Losmandy-compatible saddle. Tell us what you own and we will give you a straight answer about whether it will carry this tube for imaging as well as for visual use.\u003c\/p\u003e\n\n\u003ch3\u003e\u003cstrong\u003eBottom Line\u003c\/strong\u003e\u003c\/h3\u003e\n\u003cp\u003eIn short: a 152mm f\/8 air-spaced triplet apochromat in carbon fibre, 1216mm focal length, .75 arcsec resolution, 20.5lb, on a Losmandy dovetail with a 2.5-inch HEX focuser, and with a 99% reflective 2-inch diagonal, cradle rings and a finder base included. If you would like us to map an imaging train onto your camera before you order, send us the camera and any adapters you already have and we will work the numbers with you.\u003c\/p\u003e","brand":"Explore Scientific","offers":[{"title":"Default Title","offer_id":44012606914671,"sku":"TED15208CF-HEX33","price":5639.95,"currency_code":"CAD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0686\/0049\/6239\/files\/ed_152cf_d5d02ceb-4787-459d-b69f-6d0d8c5c71a1_compact__31997.jpg?v=1766548133"},{"product_id":"explore-scientific-ar102-air-spaced-doublet-refractor","title":"Explore Scientific AR102 102mm f\/6.5 Air-Spaced Doublet Refractor Telescope","description":"\u003ch3\u003e\u003cstrong\u003eProduct Overview\u003c\/strong\u003e\u003c\/h3\u003e\n\u003cp\u003eThe Explore Scientific AR102 is a 102mm air-spaced crown-and-flint achromatic doublet refractor with a published focal length of 663mm at f\/6.5. Explore Scientific gives the optical diameter as 101mm, the limiting magnitude as 12.5 and the resolution as 1.14 arcsec — the three figures that describe how faint this aperture reaches and how close a pair of stars can sit and still separate.\u003c\/p\u003e\n\u003cp\u003eThe tube measures 25.5″ (698mm) with the dew shield extended, and the published weight is 11.5 lbs (5.2 kg). At f\/6.5 this is a short-focus four-inch, built around bright wide-field views at low and medium power rather than long-focus planetary work. The short tube is a large part of why it stays a one-trip instrument.\u003c\/p\u003e\n\u003cp\u003eIt ships as an optical tube assembly with its accessory package: a dual-speed 2-inch Crayford focuser, a 2-inch diagonal with 99% dielectric coatings, an 8x50 finderscope with a quick-release bracket, and a cradle ring assembly carrying a 45mm wide Vixen-style dovetail plate. A mount and eyepieces are chosen separately.\u003c\/p\u003e\n\n\u003ch3\u003e\u003cstrong\u003eWho It's For\u003c\/strong\u003e\u003c\/h3\u003e\n\u003cul\u003e\n\u003cli\u003e\n\u003cstrong\u003eWide-field visual observers:\u003c\/strong\u003e a 101mm objective gathers on the order of 200 times the light a 7mm dark-adapted pupil collects, and at 663mm through a 2-inch focuser the true field stays wide enough for large open clusters and the brighter nebulae to sit inside a single view.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eObservers who set up and pack down every session:\u003c\/strong\u003e 11.5 lbs and 25.5 inches is a tube most people carry in one hand, and a refractor holds its optical alignment between sessions.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eOutreach and star-party use:\u003c\/strong\u003e nothing to collimate between events, a quick-release finder, and a dielectric diagonal already in the box.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eAnyone with mount capacity to spare:\u003c\/strong\u003e this is a good match if your mount is rated comfortably above the 11.5 lb tube once a diagonal, finder and 2-inch eyepiece are added to it.\u003c\/li\u003e\n\u003c\/ul\u003e\n\n\u003ch3\u003e\u003cstrong\u003eKey Features \u0026amp; Design\u003c\/strong\u003e\u003c\/h3\u003e\n\u003cul\u003e\n\u003cli\u003e\n\u003cstrong\u003e102mm air-spaced doublet:\u003c\/strong\u003e crown and flint elements separated by an air gap rather than cemented, with a published optical diameter of 101mm.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003e663mm focal length at f\/6.5:\u003c\/strong\u003e a short focal ratio for a four-inch refractor, which is what keeps both the tube length and the true field generous.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eLimiting magnitude 12.5:\u003c\/strong\u003e the faintest star the aperture is rated to reach.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003e1.14 arcsec resolution:\u003c\/strong\u003e the governing figure for splitting close double stars.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eDual-speed 2-inch Crayford focuser:\u003c\/strong\u003e coarse and fine motion on the same shaft, which is what makes focus repeatable at higher magnification and under a heavy 2-inch eyepiece.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003e2-inch diagonal with 99% dielectric coatings,\u003c\/strong\u003e supplied with the tube rather than sold alongside it.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eCradle ring assembly with a 45mm wide Vixen-style dovetail:\u003c\/strong\u003e the tube load spreads across two rings instead of one clamp point, and the rings allow the tube to be rotated for eyepiece position.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003e25.5″ (698mm) overall with the dew shield extended,\u003c\/strong\u003e at a published 11.5 lbs (5.2 kg).\u003c\/li\u003e\n\u003c\/ul\u003e\n\n\u003ch3\u003e\u003cstrong\u003eOptical Design\u003c\/strong\u003e\u003c\/h3\u003e\n\u003cp\u003eAn achromatic doublet brings two wavelengths of light to a common focus by pairing a crown element with a flint element. Air-spacing the pair, rather than cementing it, gives the designer two extra optical surfaces to shape and removes the cement layer as a thermal variable when the tube cools down at the start of a session.\u003c\/p\u003e\n\u003cp\u003eAn achromat is not an apochromat, and at f\/6.5 that difference is visible on the brightest targets. Venus, Jupiter, Sirius and the lunar limb will show a violet edge at high magnification. That behaviour belongs to two-element crown-and-flint designs generally rather than to this tube in particular, and it scales with magnification: at the 25x to 60x range this focal length is happiest at, it is not something that intrudes. Observers who want it reduced at high power usually add a minus-violet or fringe-killer filter to the 2-inch diagonal, and we stock those. Observers who want the colour gone rather than reduced are looking at an ED doublet or an apochromatic triplet, which is a different price class and a different tube.\u003c\/p\u003e\n\n\u003ch3\u003e\u003cstrong\u003eRecommended Uses\u003c\/strong\u003e\u003c\/h3\u003e\n\u003cul\u003e\n\u003cli\u003eLow and medium-power sweeping of open clusters, the brighter nebulae and the larger galaxies.\u003c\/li\u003e\n\u003cli\u003eLunar observing at moderate magnification, where the flat, contrasty field of a refractor shows well.\u003c\/li\u003e\n\u003cli\u003eDouble-star work within the 1.14 arcsec published resolution.\u003c\/li\u003e\n\u003cli\u003ePublic outreach, school sessions and travel, where an 11.5 lb tube that needs no collimation is the practical advantage.\u003c\/li\u003e\n\u003cli\u003eWide-field and solar-system imaging on an equatorial mount rated well above the tube weight.\u003c\/li\u003e\n\u003c\/ul\u003e\n\n\u003ch3\u003e\u003cstrong\u003eCompatibility and Accessory Notes\u003c\/strong\u003e\u003c\/h3\u003e\n\u003cul\u003e\n\u003cli\u003e\n\u003cstrong\u003eMount:\u003c\/strong\u003e not included. The published tube weight of 11.5 lbs is before the diagonal, finder and eyepiece, so the loaded tube sits higher than that. A mount with 15 lb or more of rated visual capacity is a sensible starting point, and more again for imaging.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eDovetail:\u003c\/strong\u003e the 45mm wide plate follows the Vixen-style pattern, so it drops into a Vixen saddle or a dual Vixen\/Losmandy saddle without an adapter.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eEyepieces:\u003c\/strong\u003e none included. At 663mm, a 30mm eyepiece gives 22x, a 25mm gives 27x, a 15mm gives 44x and a 9mm gives 74x. Divide 663 by the eyepiece focal length in millimetres for any other combination.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eDiagonal and barrel sizes:\u003c\/strong\u003e the supplied 2-inch diagonal takes 2-inch eyepieces, and 1.25-inch eyepieces with a 2-inch to 1.25-inch adapter.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eFilters:\u003c\/strong\u003e the 2-inch diagonal accepts 2-inch threaded filters. A minus-violet filter is the usual pairing for high-power lunar and planetary work on a fast achromat; broadband and narrowband nebula filters suit the wide-field work this focal ratio is built around.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eImaging:\u003c\/strong\u003e Explore Scientific does not publish a corrected image circle or a backfocus figure for this tube, so we are not going to quote one. Send us the camera and flattener you have in mind and we will work out what fits before you order.\u003c\/li\u003e\n\u003c\/ul\u003e\n\n\u003ch3\u003e\u003cstrong\u003eGood to Know Before You Order\u003c\/strong\u003e\u003c\/h3\u003e\n\u003cul\u003e\n\u003cli\u003e\n\u003cstrong\u003eThis is an optical tube assembly, not a complete telescope.\u003c\/strong\u003e A mount and tripod are needed to use it, and so is at least one eyepiece. We put packages together regularly and can price one against the mount you already own.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eAchromatic, not apochromatic.\u003c\/strong\u003e Colour on the brightest objects at high power is part of the design. A minus-violet filter reduces it, and at the low to medium powers this focal ratio is built for it is not the limiting factor.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eThe 25.5-inch figure includes the dew shield extended.\u003c\/strong\u003e That is the dimension to measure against a case or a car boot if the tube travels with you.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eExplore Scientific publishes no corrected image circle and no backfocus figure\u003c\/strong\u003e for the AR102, so those rows are absent from the specification table below rather than estimated. If you are planning an imaging train, we will confirm spacing with you first.\u003c\/li\u003e\n\u003c\/ul\u003e\n\n\u003ch3\u003e\u003cstrong\u003eFrequently Asked Questions\u003c\/strong\u003e\u003c\/h3\u003e\n\u003cp\u003e\u003cstrong\u003eIs it difficult to set up?\u003c\/strong\u003e\u003c\/p\u003e\n\u003cp\u003eNo. A refractor needs no collimation, so the tube is ready the moment the rings are clamped into the saddle. At 11.5 lbs it lifts onto a mount comfortably, and the finder bracket and diagonal push in and lock with thumbscrews. The only first-night task is aligning the 8x50 finder to the main tube, which takes a few minutes on a distant daytime object.\u003c\/p\u003e\n\u003cp\u003e\u003cstrong\u003eWhat mount does it need?\u003c\/strong\u003e\u003c\/p\u003e\n\u003cp\u003eOne rated comfortably above the loaded tube. The bare tube is 11.5 lbs and the diagonal, finder and a 2-inch eyepiece add to that, so around 15 lbs of rated visual capacity is a reasonable floor and more is better for photography. Tell us what you have and we will give you a straight answer on whether it will carry this.\u003c\/p\u003e\n\u003cp\u003e\u003cstrong\u003eDoes it come with eyepieces?\u003c\/strong\u003e\u003c\/p\u003e\n\u003cp\u003eNo. The 2-inch dielectric diagonal, the 8x50 finderscope and the cradle rings with dovetail are included; eyepieces are chosen separately to suit the 663mm focal length.\u003c\/p\u003e\n\u003cp\u003e\u003cstrong\u003eWill I see colour around bright objects?\u003c\/strong\u003e\u003c\/p\u003e\n\u003cp\u003eOn Venus, Jupiter, Sirius and the edge of the Moon at high magnification, yes — that is what a crown-and-flint doublet does. On clusters, nebulae and galaxies at the powers this f\/6.5 tube is built for, it is not something that shows.\u003c\/p\u003e\n\n\u003ch3\u003e\u003cstrong\u003eBottom Line\u003c\/strong\u003e\u003c\/h3\u003e\n\u003cp\u003eIn short: a 102mm f\/6.5 air-spaced achromat at 663mm focal length, supplied as an 11.5 lb tube with a dual-speed 2-inch Crayford focuser, a 99% dielectric 2-inch diagonal, an 8x50 finder and a Vixen-style dovetail — four inches of low-maintenance aperture built for wide, bright fields. If you are matching it to a mount you already own or working out a first pair of eyepieces for 663mm, send us the details and we will sort it out with you.\u003c\/p\u003e","brand":"Explore Scientific","offers":[{"title":"Default Title","offer_id":44012795723887,"sku":"DAR102065-02","price":634.95,"currency_code":"CAD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0686\/0049\/6239\/files\/ar_10211__08092.png?v=1766548214"},{"product_id":"explore-scientific-127mm-fcd100-apo","title":"Explore Scientific FCD100 Series 127mm f\/7.5 Air-Spaced Triplet ED APO Refractor Telescope","description":"\u003ch3\u003e\u003cstrong\u003eProduct Overview\u003c\/strong\u003e\u003c\/h3\u003e\n\u003cp\u003eThe Explore Scientific FCD100 Series 127mm is a five-inch air-spaced triplet apochromatic refractor with a focal length of 952mm at f\/7.5. The objective is built around Hoya FCD100 extra-low-dispersion glass, and Explore Scientific publishes a limiting magnitude of 13 and a resolution of .9 arcsec for it. The tube is aluminium, finished in white, and measures 41.75″ (1060mm) with the dew shield extended, 33.25″ (849mm) with it retracted, over a 130mm outside diameter, at a published 18lb (8.2kg).\u003c\/p\u003e\n\u003cp\u003eIt is supplied as an optical tube assembly. The published package covers a 2.5-inch focuser rated to carry up to 10 lbs of imaging gear, an integrated retractable dew shield, a cradle ring with a carry handle, and a Vixen-style dovetail plate. Enhanced multi-layer coatings are applied to suppress aberrations. No mount and no eyepieces are listed in the vendor's package.\u003c\/p\u003e\n\n\u003ch3\u003e\u003cstrong\u003eWho It's For\u003c\/strong\u003e\u003c\/h3\u003e\n\u003cul\u003e\n\u003cli\u003e\n\u003cstrong\u003eDeep-sky imagers\u003c\/strong\u003e who want a five-inch refractor with a focuser rated for a real imaging train rather than a token one. The 10 lb focuser rating is the figure that matters when a cooled camera, filter wheel, off-axis guider and rotator are all hanging off the back.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eHigh-power visual observers:\u003c\/strong\u003e at f\/7.5 and 952mm this is a long enough refractor to hold correction on the Moon, planets and double stars, with .9 arcsec of published resolution to work with.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eObservers stepping up from an 80mm or 100mm ED tube\u003c\/strong\u003e who want more aperture without moving to a mirror system and the collimation and cool-down that comes with one. This is a good match if you already run a mount with headroom well above 18 lb.\u003c\/li\u003e\n\u003c\/ul\u003e\n\n\u003ch3\u003e\u003cstrong\u003eKey Features \u0026amp; Design\u003c\/strong\u003e\u003c\/h3\u003e\n\u003cul\u003e\n\u003cli\u003e\n\u003cstrong\u003e127mm air-spaced triplet objective:\u003c\/strong\u003e three elements in the objective cell, separated by air gaps rather than cemented.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eHoya FCD100 ED glass:\u003c\/strong\u003e the low-dispersion element in the group, which is what pulls the design into apochromatic territory.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003e952mm focal length at f\/7.5:\u003c\/strong\u003e a moderate focal ratio for an apochromat, which eases the correction burden on the objective and keeps the field better behaved than a very fast triplet.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003e2.5-inch focuser rated to 10 lbs:\u003c\/strong\u003e a load rating Explore Scientific publishes specifically for imaging gear.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eIntegrated retractable dew shield:\u003c\/strong\u003e it slides back over the tube, which is where the 8.5-inch difference between the two published tube lengths comes from.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eEnhanced multi-layer deposition coatings\u003c\/strong\u003e on the optical surfaces, applied to raise transmission and hold contrast.\u003c\/li\u003e\n\u003c\/ul\u003e\n\n\u003ch3\u003e\u003cstrong\u003eOptical Design\u003c\/strong\u003e\u003c\/h3\u003e\n\u003cp\u003eA two-element achromat brings two wavelengths to a common focus and leaves a visible residual — the secondary spectrum — around bright objects. A three-element apochromat adds a degree of freedom: with one element made of extra-low-dispersion glass, the designer can bring three widely separated wavelengths to essentially the same focal plane instead of two. The practical result is that the violet and deep-red ends of the spectrum land close enough to the visual focus that colour fringing on Venus, Jupiter and the lunar limb stops being a feature of the view.\u003c\/p\u003e\n\u003cp\u003eFCD100 is the ED glass type in this objective. Its job is dispersion control: it bends the different wavelengths by more similar amounts than ordinary crown or flint glass does, so the two mating elements have less residual colour to correct. Air spacing rather than cementing gives the design six optical surfaces to shape instead of four, and it removes a cement layer as a thermal variable in a five-inch lens — a real consideration in a lens this size cooling down through an evening.\u003c\/p\u003e\n\u003cp\u003eExplore Scientific does not publish a corrected image circle or a backfocus distance for this tube, so those rows are absent from the specifications below rather than estimated. If you are assembling an imaging train, send us the camera and flattener you have in mind and we will work the spacing out with you.\u003c\/p\u003e\n\n\u003ch3\u003e\u003cstrong\u003eRecommended Uses\u003c\/strong\u003e\u003c\/h3\u003e\n\u003cul\u003e\n\u003cli\u003eDeep-sky astrophotography on a suitably rated equatorial mount, with a flattener matched to your sensor.\u003c\/li\u003e\n\u003cli\u003eHigh-magnification visual work on the Moon, planets and double stars, where .9 arcsec of published resolution sets the ceiling.\u003c\/li\u003e\n\u003cli\u003eLunar and planetary imaging with a focal extender ahead of a planetary camera.\u003c\/li\u003e\n\u003c\/ul\u003e\n\n\u003ch3\u003e\u003cstrong\u003eCompatibility and Accessory Notes\u003c\/strong\u003e\u003c\/h3\u003e\n\u003cul\u003e\n\u003cli\u003e\n\u003cstrong\u003eMount:\u003c\/strong\u003e not included. The published tube weight is 18lb (8.2kg) bare, before a diagonal, finder, camera or eyepiece, so a mount rated comfortably above that is the sensible starting point — and more again for imaging, where tracking accuracy rather than raw capacity is the constraint.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eDovetail:\u003c\/strong\u003e the supplied plate is Vixen-style, so it seats in any Vixen saddle and in the dual-format saddles that take both Vixen and Losmandy plates.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eEyepieces and diagonal:\u003c\/strong\u003e not listed in the published package. The 2.5-inch focuser takes 2-inch accessories with the appropriate adapter, and 2-inch is the format most observers build around at this focal length.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eMagnification:\u003c\/strong\u003e 952mm ÷ eyepiece focal length. A 30mm gives 32x, a 20mm gives 48x, a 9mm gives 106x, a 5mm gives 190x.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eFocal extenders:\u003c\/strong\u003e a 2x extender takes the system to 1904mm at f\/15, which is planetary imaging territory in steady air.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eImaging train:\u003c\/strong\u003e the 10 lb focuser rating covers most cooled-camera trains, and we can go through yours item by item if you would like a second opinion on the load.\u003c\/li\u003e\n\u003c\/ul\u003e\n\n\u003ch3\u003e\u003cstrong\u003eGood to Know Before You Order\u003c\/strong\u003e\u003c\/h3\u003e\n\u003cul\u003e\n\u003cli\u003e\n\u003cstrong\u003eThis is an optical tube assembly, not a complete telescope.\u003c\/strong\u003e A mount, a tripod, a diagonal and at least one eyepiece are separate items. We put packages like this together regularly — tell us how you plan to use it and we will price the whole thing out.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eIt is a 41.75-inch tube with the dew shield extended.\u003c\/strong\u003e That length is worth measuring against your case, your car and your observing space before ordering; the shield retracts to bring the tube down to 33.25 inches for transport.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eThe published 18lb is the bare tube.\u003c\/strong\u003e Loaded with a diagonal, finder and a 2-inch eyepiece, or with a full imaging train, it sits meaningfully higher, which is why mount headroom matters more than a bare-minimum rating.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eNo corrected image circle or backfocus figure is published\u003c\/strong\u003e for this tube, so we quote neither. Send us your camera and we will tell you what we can establish about the spacing.\u003c\/li\u003e\n\u003c\/ul\u003e\n\n\u003ch3\u003e\u003cstrong\u003eFrequently Asked Questions\u003c\/strong\u003e\u003c\/h3\u003e\n\u003cp\u003e\u003cstrong\u003eIs it difficult to set up?\u003c\/strong\u003e\u003c\/p\u003e\n\u003cp\u003eThe optics need nothing from you — a refractor holds its collimation, so the tube is ready the moment it is on the mount. The work is physical rather than technical: 18lb and nearly 42 inches is a two-handed lift onto a saddle, and it goes more smoothly with the mount already levelled and the counterweights roughly positioned first.\u003c\/p\u003e\n\u003cp\u003e\u003cstrong\u003eWhat mount does it need?\u003c\/strong\u003e\u003c\/p\u003e\n\u003cp\u003eOne with capacity well above the 18lb bare tube weight, since the diagonal, finder and eyepiece or camera all add to it. For imaging, the useful figure is usually around half a mount's visual rating. Tell us what you own and we will give you an honest read on whether it will carry this tube.\u003c\/p\u003e\n\u003cp\u003e\u003cstrong\u003eWill I see false colour?\u003c\/strong\u003e\u003c\/p\u003e\n\u003cp\u003eAn air-spaced triplet using FCD100 ED glass is built specifically to remove it. On the brightest targets at very high power some residual is inherent to any refracting design, but it is not the limiting factor in this telescope the way it is in an achromat.\u003c\/p\u003e\n\u003cp\u003e\u003cstrong\u003eDoes it come with eyepieces or a diagonal?\u003c\/strong\u003e\u003c\/p\u003e\n\u003cp\u003eNeither is listed in the vendor's published package. The tube arrives with its 2.5-inch focuser, dew shield, cradle ring and Vixen dovetail. We can supply a diagonal and a starting eyepiece set alongside it.\u003c\/p\u003e\n\n\u003ch3\u003e\u003cstrong\u003eBottom Line\u003c\/strong\u003e\u003c\/h3\u003e\n\u003cp\u003eIn short: a 127mm f\/7.5 air-spaced triplet apochromat on FCD100 ED glass, 952mm focal length, with a 2.5-inch focuser rated to 10 lbs of imaging gear, a retractable dew shield, a cradle ring with carry handle and a Vixen dovetail — five inches of low-maintenance refractor aperture that serves visual and photographic use equally. If you are matching it to a mount or planning the imaging train, send us the details and we will work through the fit with you before you order.\u003c\/p\u003e","brand":"Explore Scientific","offers":[{"title":"Default Title","offer_id":44013369589871,"sku":"FCD100-127075-02","price":3524.95,"currency_code":"CAD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0686\/0049\/6239\/files\/FCD100_127mm_1__75589.jpg?v=1766551589"},{"product_id":"explore-scientific-102mm-fcd100","title":"Explore Scientific ED102 FCD-100 Series 102mm f\/7 Air-Spaced Triplet Refractor Telescope","description":"\u003ch3\u003e\u003cstrong\u003eProduct Overview\u003c\/strong\u003e\u003c\/h3\u003e\n\u003cp\u003eThe Explore Scientific ED102 FCD-100 Series is a 102mm air-spaced triplet apochromatic refractor with a focal length of 714mm working at f\/7. The centre element is HOYA FCD100 extra-low-dispersion glass, and every air-to-glass surface carries Explore Scientific's EMD (Enhanced Multi-Layer Deposition) coating. For this aperture Explore Scientific publishes a limiting magnitude of 12.5 and a resolution of 1.14 arcsec.\u003c\/p\u003e\n\u003cp\u003eThe tube measures 30.5″ (774mm) with the dew shield extended and 23.75″ (603mm) with it retracted, over a 119mm outside diameter, at a published weight of 10.9 lb (4.94 kg). It carries a 2.5-inch focuser rated by Explore Scientific for imaging loads to 10 lb, and rides on a 45mm wide V-block dovetail of the Vixen pattern.\u003c\/p\u003e\n\n\u003ch3\u003e\u003cstrong\u003eWho It's For\u003c\/strong\u003e\u003c\/h3\u003e\n\u003cul\u003e\n\u003cli\u003e\n\u003cstrong\u003eWide-field imagers:\u003c\/strong\u003e 714mm at f\/7 puts the larger emission nebulae, the Andromeda core and the bigger open clusters inside a single APS-C frame, and the triplet holds star colour to the corners of the illuminated field.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eVisual observers who want colour-free high power:\u003c\/strong\u003e 1.14 arcsec of published resolution is enough for the Cassini division, the Jovian festoons and tight double pairs, with none of the violet halo an achromat shows on those targets.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eTravelling observers:\u003c\/strong\u003e a 23.75-inch retracted tube at 10.9 lb fits luggage and small cases in a way a six-inch instrument does not.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eObservers building a second imaging rig:\u003c\/strong\u003e this is a good match if you already own a mount rated comfortably above 11 lb and want a refractor that can front an imaging train today and guide a larger scope later.\u003c\/li\u003e\n\u003c\/ul\u003e\n\n\u003ch3\u003e\u003cstrong\u003eKey Features \u0026amp; Design\u003c\/strong\u003e\u003c\/h3\u003e\n\u003cul\u003e\n\u003cli\u003e\n\u003cstrong\u003e102mm air-spaced triplet:\u003c\/strong\u003e three elements in a single cell with air gaps rather than cement, built around a HOYA FCD100 extra-low-dispersion centre element.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003e714mm focal length at f\/7:\u003c\/strong\u003e short enough for wide-field framing, long enough that eyepieces in the 5mm to 9mm range reach usable planetary powers.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eEMD enhanced multi-layer coatings\u003c\/strong\u003e on the air-to-glass surfaces, which is where transmission and stray-light control are won or lost in a three-element objective.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003e2.5-inch focuser rated to 10 lb:\u003c\/strong\u003e Explore Scientific specifies the load capacity, which is the figure that matters once a camera, filter wheel and off-axis guider are hanging off the back.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eRetracting dew shield:\u003c\/strong\u003e 30.5″ (774mm) extended, 23.75″ (603mm) retracted, so the transport length is nearly seven inches shorter than the working length.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003e119mm tube diameter\u003c\/strong\u003e with a 45mm wide V-block dovetail similar to the Vixen standard.\u003c\/li\u003e\n\u003c\/ul\u003e\n\n\u003ch3\u003e\u003cstrong\u003eOptical Design\u003c\/strong\u003e\u003c\/h3\u003e\n\u003cp\u003eA triplet apochromat uses three elements to bring three wavelengths to a common focus, where a doublet manages two. The practical result is that the secondary spectrum — the residual colour error left over after the primary correction — drops to a level where it stops being visible on bright stars and stops bloating blue channels in a stacked image. The FCD100 glass in the centre element is a fluoro-crown type with very low dispersion, which is what makes that three-wavelength correction achievable in a cell only 102mm across.\u003c\/p\u003e\n\u003cp\u003eAir spacing rather than cementing gives the designer additional surfaces to work with and removes the cement layer as a thermal variable. It also means the objective cools as three separate pieces of glass, so a triplet takes longer to reach thermal equilibrium than a doublet of the same aperture. In practice that is twenty to forty minutes outside before the highest powers settle, which is worth knowing when planning a session.\u003c\/p\u003e\n\u003cp\u003eAt f\/7 the native field is not flat. Refractor objectives produce a curved focal surface, and across a large sensor that shows as stars stretching at the corners while the centre is sharp. A dedicated field flattener corrects it. Explore Scientific does not publish a corrected image circle or a backfocus figure for this tube, so no number is quoted here — we can work out the spacing with you against the camera and flattener you have in mind.\u003c\/p\u003e\n\n\u003ch3\u003e\u003cstrong\u003eRecommended Uses\u003c\/strong\u003e\u003c\/h3\u003e\n\u003cul\u003e\n\u003cli\u003eWide-field deep-sky imaging of nebulae, large clusters and the brighter galaxies at 714mm.\u003c\/li\u003e\n\u003cli\u003eHigh-power visual work on the Moon, planets and double stars, where the 1.14 arcsec resolution figure governs.\u003c\/li\u003e\n\u003cli\u003eLunar and solar-system imaging with a focal extender to raise the effective focal length.\u003c\/li\u003e\n\u003cli\u003eTravel and dark-site trips where the 23.75-inch retracted length matters.\u003c\/li\u003e\n\u003c\/ul\u003e\n\n\u003ch3\u003e\u003cstrong\u003eCompatibility and Accessory Notes\u003c\/strong\u003e\u003c\/h3\u003e\n\u003cul\u003e\n\u003cli\u003e\n\u003cstrong\u003eMount:\u003c\/strong\u003e not part of the published package. At 10.9 lb bare, a mount rated at 25 lb or more gives the margin imaging wants once a camera and accessories are added.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eDovetail:\u003c\/strong\u003e the 45mm wide V-block seats in Vixen-style saddles, including dual-fit saddles that take both Vixen and Losmandy plates.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eEyepieces:\u003c\/strong\u003e at 714mm, a 30mm eyepiece gives 24x, a 20mm gives 36x, a 9mm gives 79x and a 5mm gives 143x.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eFocal extenders:\u003c\/strong\u003e a 2x extender takes the system to 1428mm at f\/14 for lunar and planetary imaging.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eImaging train:\u003c\/strong\u003e the 2.5-inch focuser is specified to 10 lb, which accommodates most cooled CMOS cameras with a filter wheel and off-axis guider.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eField flattener:\u003c\/strong\u003e needed for a flat field across an APS-C or larger sensor. Send us the camera and we will work through the spacing with you.\u003c\/li\u003e\n\u003c\/ul\u003e\n\n\u003ch3\u003e\u003cstrong\u003eGood to Know Before You Order\u003c\/strong\u003e\u003c\/h3\u003e\n\u003cul\u003e\n\u003cli\u003e\n\u003cstrong\u003eThis is an optical tube assembly.\u003c\/strong\u003e A mount, tripod and at least one eyepiece are separate items, and Explore Scientific does not publish an itemised box-contents list for this tube. We can check what is in the carton with our rep before you order, and put a package together if that is simpler.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eExplore Scientific publishes two weight figures for this model.\u003c\/strong\u003e The current spec sheet for item FCD100-10207-02 lists 10.9 lb (4.94 kg); an earlier sheet for the aluminium FCD100-10207-01 listed 12 lb (5.4 kg). Both are shown here as published rather than averaged.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eA triplet needs cooling time.\u003c\/strong\u003e Three separate elements reach ambient temperature more slowly than two, so the sharpest high-power views arrive some time after the tube goes outside rather than immediately.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eNo corrected image circle or backfocus figure is published\u003c\/strong\u003e for this tube, so those rows are absent from the specifications rather than estimated. If you are planning an imaging train, tell us the camera and flattener and we will map the spacing out with you.\u003c\/li\u003e\n\u003c\/ul\u003e\n\n\u003ch3\u003e\u003cstrong\u003eFrequently Asked Questions\u003c\/strong\u003e\u003c\/h3\u003e\n\u003cp\u003e\u003cstrong\u003eIs it difficult to set up?\u003c\/strong\u003e\u003c\/p\u003e\n\u003cp\u003eThe optics need nothing — a refractor holds its collimation, so there is no alignment step before observing. The work is mounting it: 10.9 lb onto a levelled saddle, dovetail clamped, dew shield pulled out, and then a cooling period before the highest powers look their best.\u003c\/p\u003e\n\u003cp\u003e\u003cstrong\u003eWhat mount does it want?\u003c\/strong\u003e\u003c\/p\u003e\n\u003cp\u003eSomething rated well above 10.9 lb once a diagonal, finder and eyepiece or an imaging train are added. For visual work a 20 lb mount is comfortable; for imaging, 25 lb or more gives the settling margin that guiding depends on. Tell us what you have and we will give you a straight answer on the fit.\u003c\/p\u003e\n\u003cp\u003e\u003cstrong\u003eWhat does FCD100 glass actually do?\u003c\/strong\u003e\u003c\/p\u003e\n\u003cp\u003eIt is a low-dispersion fluoro-crown glass that spreads wavelengths less than ordinary optical glass. Used as the centre element of a triplet, it allows three wavelengths to be brought to a common focus, which is what removes the violet halo an achromatic doublet shows on Venus, Sirius and the lunar limb.\u003c\/p\u003e\n\u003cp\u003e\u003cstrong\u003eWill it show colour fringing?\u003c\/strong\u003e\u003c\/p\u003e\n\u003cp\u003eAn apochromatic triplet is designed to bring that below the visible threshold. On the very brightest targets at very high power a trace of residual colour is inherent to any refracting design, but it is a different order of magnitude from what a two-element achromat produces.\u003c\/p\u003e\n\n\u003ch3\u003e\u003cstrong\u003eBottom Line\u003c\/strong\u003e\u003c\/h3\u003e\n\u003cp\u003eIn short: a 102mm f\/7 air-spaced triplet on HOYA FCD100 glass, 714mm focal length, 10.9 lb, with a 2.5-inch focuser rated to 10 lb and a Vixen-pattern dovetail — a four-inch apochromat short enough to travel and capable enough to image with. If you are matching it to a mount or an existing camera, send us the details and we will work out the fit with you before you order.\u003c\/p\u003e","brand":"Explore Scientific","offers":[{"title":"Explore Scientific Field Flattener f\/5 to f\/7","offer_id":44013369720943,"sku":"FCD100-10207-02","price":2396.95,"currency_code":"CAD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0686\/0049\/6239\/files\/explore_scientific_fcd100_10207_01_102mm__86741.jpg?v=1766551603"},{"product_id":"102mm-fcd100-air-spaced-triplet-ed-apo-in-carbon-fiber","title":"Explore Scientific FCD-100 Series 102mm Carbon Fiber Air-Spaced Triplet ED Apo Refractor","description":"\u003ch3\u003e\u003cstrong\u003eProduct Overview\u003c\/strong\u003e\u003c\/h3\u003e\n\u003cp\u003eThe Explore Scientific FCD-100 Series 102mm carbon fiber apochromat is a four-inch refractor built around an air-spaced triplet objective made with FCD-100 extra-low-dispersion glass, carried in a carbon fiber optical tube. It is catalogued as item FCD100-10207-CF-01 — the carbon fiber version of the 102mm FCD-100 apochromat, distinct from the aluminium-tube 102mm which carries its own separate item number.\u003c\/p\u003e\n\u003cp\u003eExplore Scientific does not currently publish a specification table for this carbon fiber configuration. Focal length, focal ratio, tube length, focuser travel, dovetail pattern, backfocus and weight are therefore absent from the specifications below rather than estimated. The figures belonging to the aluminium-tube 102mm are not carried across to this listing, because that is a different model and its numbers are not ours to lend. What the model designation itself establishes is the part that governs the optics: 102mm of clear aperture, three elements in an air-spaced triplet, FCD-100 ED glass, and a carbon fiber tube.\u003c\/p\u003e\n\u003cp\u003eAperture on its own settles a good deal. A 102mm objective gathers roughly 212 times the light of a fully dark-adapted 7mm eye pupil, and Dawes' criterion for a 102mm aperture works out to about 1.14 arcseconds — the separation at which a tight double star begins to resolve into two points. Both are calculations from the aperture figure rather than published specifications.\u003c\/p\u003e\n\n\u003ch3\u003e\u003cstrong\u003eWho It's For\u003c\/strong\u003e\u003c\/h3\u003e\n\u003cul\u003e\n\u003cli\u003e\n\u003cstrong\u003eObservers who want colour-free high power in a four-inch tube:\u003c\/strong\u003e a triplet apochromat is designed to bring three wavelengths to a common focus, which is what removes the violet halo that a two-element achromat leaves around Venus, Jupiter and the lunar limb.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eDeep-sky imagers:\u003c\/strong\u003e the combination of a triplet objective and a carbon fiber tube targets the two things that spoil a long exposure — colour spread across the star field, and focus drifting as the night cools.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003ePeople who already own a capable equatorial or alt-az mount.\u003c\/strong\u003e This is a good match if you have a mount with capacity to spare and want a four-inch apochromat to put on it.\u003c\/li\u003e\n\u003c\/ul\u003e\n\n\u003ch3\u003e\u003cstrong\u003eKey Features \u0026amp; Design\u003c\/strong\u003e\u003c\/h3\u003e\n\u003cul\u003e\n\u003cli\u003e\n\u003cstrong\u003e102mm clear aperture:\u003c\/strong\u003e four inches of light grasp, with a theoretical resolution near 1.14 arcseconds by Dawes' criterion.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eAir-spaced triplet objective:\u003c\/strong\u003e three elements with air gaps between them rather than cement, giving the designer six optical surfaces to shape instead of the four a cemented pair offers.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eFCD-100 extra-low-dispersion glass:\u003c\/strong\u003e an ED glass type chosen for its low dispersion, which is the property that lets a triplet close the secondary spectrum rather than merely reduce it.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eCarbon fiber optical tube:\u003c\/strong\u003e carbon composite has a far lower coefficient of thermal expansion than aluminium, so the distance between objective and focal plane changes less as the ambient temperature falls through the night.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003ePublished data is limited:\u003c\/strong\u003e the model designation is the whole of what Explore Scientific states publicly for this configuration, so the rest of the table reads \"Not published by vendor\" instead of carrying a borrowed figure.\u003c\/li\u003e\n\u003c\/ul\u003e\n\n\u003ch3\u003e\u003cstrong\u003eOptical Design\u003c\/strong\u003e\u003c\/h3\u003e\n\u003cp\u003eAn apochromatic triplet works on the same principle as an achromatic doublet, taken a step further. A doublet pairs a crown element with a flint element so that two wavelengths — typically in the red and the blue — land on the same focal plane, leaving a residual violet focus error known as the secondary spectrum. A triplet adds a third element, usually with an extra-low-dispersion glass such as FCD-100 in the middle of the stack, and brings a third wavelength onto that plane as well. The residual colour error drops by roughly an order of magnitude, which is why bright stars in an apochromat show as clean points rather than as points wearing a purple ring.\u003c\/p\u003e\n\u003cp\u003eAir-spacing the elements rather than cementing them serves two ends. It gives the optical designer additional free surfaces to shape and additional degrees of freedom in balancing spherical aberration against colour correction. It also removes the cement layer as a thermal variable: in a four-inch objective, a bonded interface between glasses of differing expansion rates is one more thing that has to settle as the lens cools toward ambient.\u003c\/p\u003e\n\u003cp\u003eThe carbon fiber tube is doing thermal work of its own. Every refractor has a fixed distance from the objective to the focal plane, and every tube material changes length as it cools. Aluminium moves enough over a twenty-degree evening drop to be visible in a critically focused image at high magnification or on a small imaging pixel scale. Carbon composite moves far less, so a focus position set at the start of an imaging run holds closer to true through the session. The same stiffness-to-weight advantage also keeps flexure between the objective cell and the focuser lower for a given tube mass. What the design cannot settle without a published focal length is the focal ratio, the field any eyepiece will deliver, or the illuminated image circle at the camera — and those we would rather leave blank than guess at.\u003c\/p\u003e\n\n\u003ch3\u003e\u003cstrong\u003eRecommended Uses\u003c\/strong\u003e\u003c\/h3\u003e\n\u003cul\u003e\n\u003cli\u003eHigh-power visual observing of the Moon, planets and double stars, where colour correction is the limiting factor rather than aperture.\u003c\/li\u003e\n\u003cli\u003eDeep-sky imaging, where a triplet objective keeps star colour tight across the frame.\u003c\/li\u003e\n\u003cli\u003eLong imaging sessions through a falling temperature, where a low-expansion tube reduces the number of refocus stops.\u003c\/li\u003e\n\u003c\/ul\u003e\n\n\u003ch3\u003e\u003cstrong\u003eCompatibility and Accessory Notes\u003c\/strong\u003e\u003c\/h3\u003e\n\u003cul\u003e\n\u003cli\u003e\n\u003cstrong\u003eMount:\u003c\/strong\u003e the tube weight is not published for this configuration, so a mount recommendation from us would be a guess. We can obtain the figure from Explore Scientific and match it against the mount you own before you order.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eDovetail:\u003c\/strong\u003e the pattern supplied with the carbon fiber version is not stated on the vendor page. Vixen-style and Losmandy-style saddles are the two common standards, and we can tell you which one applies once we have it in writing.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eEyepieces and magnification:\u003c\/strong\u003e magnification is telescope focal length divided by eyepiece focal length, so without a published focal length for this tube we are not going to quote example magnifications.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eField flatteners and reducers:\u003c\/strong\u003e a triplet apochromat corrects colour, not field curvature, so imaging across an APS-C or full-frame sensor generally calls for a flattener matched to the focal length. That match depends on figures the vendor has not published here, so we would sort the spacing out with you rather than sell a flattener blind.\u003c\/li\u003e\n\u003c\/ul\u003e\n\n\u003ch3\u003e\u003cstrong\u003eGood to Know Before You Order\u003c\/strong\u003e\u003c\/h3\u003e\n\u003cul\u003e\n\u003cli\u003e\n\u003cstrong\u003eExplore Scientific publishes no specification table for the carbon fiber 102mm.\u003c\/strong\u003e Focal length, focal ratio, focuser type, tube length, dovetail and weight are all absent from their page for this item number. Rather than lift them from the aluminium-tube model, we have left those rows blank — and if any one of them is the deciding factor for you, we will put the question to our Explore Scientific rep and come back with an answer in writing.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eThe in-the-box list is also unpublished.\u003c\/strong\u003e Whether a diagonal, finder or rings ship with this configuration is not stated, so we will confirm exactly what is in the carton with the distributor before anything leaves here.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eCarbon fiber reduces focus drift rather than eliminating it.\u003c\/strong\u003e Long imaging runs still benefit from periodic refocusing or an autofocus routine, and we stock motorised focusers that handle that automatically.\u003c\/li\u003e\n\u003c\/ul\u003e\n\n\u003ch3\u003e\u003cstrong\u003eFrequently Asked Questions\u003c\/strong\u003e\u003c\/h3\u003e\n\u003cp\u003e\u003cstrong\u003eIs it difficult to set up?\u003c\/strong\u003e\u003c\/p\u003e\n\u003cp\u003eNo. A refractor holds its collimation from the factory, so there is nothing to align before first light — the tube goes into the saddle, the diagonal and eyepiece go into the focuser, and it is ready. The only real work is balancing the mount once the tube is on it.\u003c\/p\u003e\n\u003cp\u003e\u003cstrong\u003eWhat magnification will it give?\u003c\/strong\u003e\u003c\/p\u003e\n\u003cp\u003eThat depends on the focal length, and Explore Scientific has not published one for this configuration. We would rather ask them than quote a number we cannot stand behind, so if the answer matters to your eyepiece plan, ask us and we will get it.\u003c\/p\u003e\n\u003cp\u003e\u003cstrong\u003eWhat does FCD-100 glass actually do?\u003c\/strong\u003e\u003c\/p\u003e\n\u003cp\u003eIt is an extra-low-dispersion optical glass. Dispersion is the tendency of glass to bend different wavelengths by different amounts, which is the root cause of chromatic aberration. A low-dispersion element in the middle of a triplet lets the design bring red, green and blue essentially to the same focus instead of leaving violet behind.\u003c\/p\u003e\n\u003cp\u003e\u003cstrong\u003eWhy a carbon fiber tube instead of aluminium?\u003c\/strong\u003e\u003c\/p\u003e\n\u003cp\u003eThermal stability and stiffness for the mass. Carbon composite changes length far less than aluminium as the night cools, which keeps focus closer to where you set it, and it is rigid without being heavy.\u003c\/p\u003e\n\u003cp\u003e\u003cstrong\u003eCan I image with it?\u003c\/strong\u003e\u003c\/p\u003e\n\u003cp\u003eIt is built for it — a triplet apochromat on a low-expansion tube is a deep-sky imaging configuration. The accessories that go with it (flattener, spacers, filter drawer) depend on the focal length and backfocus, which is where we can help once those figures are in hand.\u003c\/p\u003e\n\n\u003ch3\u003e\u003cstrong\u003eBottom Line\u003c\/strong\u003e\u003c\/h3\u003e\n\u003cp\u003eIn short: a 102mm air-spaced triplet apochromat using FCD-100 ED glass in a carbon fiber tube — four inches of three-colour correction on a low-expansion tube, with a specification table Explore Scientific has not yet published for this particular item number. If there is a figure you need before committing, send us the question and we will get it from Explore Scientific and pass on exactly what they tell us.\u003c\/p\u003e","brand":"Explore Scientific","offers":[{"title":"Default Title","offer_id":44013376045167,"sku":"FCD100-10207-CF-01","price":2678.95,"currency_code":"CAD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0686\/0049\/6239\/files\/FCD100_102ED_CF_Burst__17456.jpg?v=1766552108"},{"product_id":"127mm-fcd100-air-spaced-triplet-ed-apo-in-carbon-fiber","title":"Explore Scientific FCD100 Series ED127 127mm f\/7.5 Carbon Fiber Air-Spaced Triplet APO Refractor Telescope","description":"\u003ch3\u003e\u003cstrong\u003eProduct Overview\u003c\/strong\u003e\u003c\/h3\u003e\n\u003cp\u003eThe Explore Scientific ED127 FCD100 Series is a 127mm air-spaced triplet apochromatic refractor with a focal length of 952mm at f\/7.5, built into a carbon fiber optical tube. The centre element of the triplet is HOYA FCD100 extra-low-dispersion glass, and the front and rear elements are air-spaced against it rather than cemented. Explore Scientific publishes a limiting magnitude of 13 and a resolution figure of .9 arcsec for this aperture.\u003c\/p\u003e\n\u003cp\u003eIt is supplied as an optical tube assembly with a 2.5″ HEX focuser rated to carry 10 lb of imaging equipment, and a Vixen-pattern dovetail. The tube measures 41.75″ (1060mm) with the dew shield extended and 33.25″ (849mm) with it retracted, 145mm across, and weighs 14 lb (6.4 kg). No mount and no eyepieces are included.\u003c\/p\u003e\n\u003ch3\u003e\u003cstrong\u003eWho It's For\u003c\/strong\u003e\u003c\/h3\u003e\n\u003cul\u003e\n\u003cli\u003e\n\u003cstrong\u003eDeep-sky imagers:\u003c\/strong\u003e 952mm at f\/7.5 is a long-enough focal length for galaxies and small nebulae without becoming an autoguiding problem, and the 2.5″ HEX focuser is specified to hold 10 lb of camera, filter wheel and rotator without sagging.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eVisual observers who want colour-free high power:\u003c\/strong\u003e an air-spaced triplet using FCD100 glass is built to bring three wavelengths to a common focus, which is what removes the violet halo an achromat shows on Venus, Jupiter and the lunar limb.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eObservers who travel to dark sites:\u003c\/strong\u003e this is a good match if you want five inches of apochromatic aperture that one person can carry to the car in a single trip. The carbon fiber tube is the reason the published weight is 14 lb rather than what a comparable aluminium tube would read.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eOwners of mid-capacity equatorial mounts:\u003c\/strong\u003e this is a good match if your mount is rated comfortably above the loaded weight of a 14 lb tube plus rings, diagonal, finder and camera train.\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003ch3\u003e\u003cstrong\u003eKey Features \u0026amp; Design\u003c\/strong\u003e\u003c\/h3\u003e\n\u003cul\u003e\n\u003cli\u003e\n\u003cstrong\u003e127mm air-spaced triplet:\u003c\/strong\u003e three elements with air gaps between them, rather than a cemented pair, giving the designer additional surfaces to work with and removing cement as a thermal variable in a five-inch lens.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eHOYA FCD100 ED glass:\u003c\/strong\u003e a high-grade extra-low-dispersion type used for the centre element, chosen for how tightly it brings the red, green and blue focal points together.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003e952mm focal length at f\/7.5:\u003c\/strong\u003e a moderate focal ratio that keeps the image scale useful for galaxies and planetary detail while remaining tractable for imaging exposures.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003e2.5″ HEX focuser:\u003c\/strong\u003e rated by Explore Scientific to support up to 10 lb of imaging equipment, so a camera, filter wheel and off-axis guider can ride on it together.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eCarbon fiber optical tube:\u003c\/strong\u003e stiffness per unit weight is the point — it is what allows a 127mm triplet to be published at 14 lb (6.4 kg).\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eRetracting dew shield:\u003c\/strong\u003e 41.75″ (1060mm) extended, 33.25″ (849mm) retracted, which is the figure that matters for a case or a back seat.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eVixen-pattern dovetail\u003c\/strong\u003e for mounting, on a tube 145mm in outside diameter.\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003ch3\u003e\u003cstrong\u003eOptical Design\u003c\/strong\u003e\u003c\/h3\u003e\n\u003cp\u003eA doublet achromat brings two wavelengths to a common focus and leaves a residual violet fringe on the brightest targets. A triplet apochromat adds a third element so that three widely separated wavelengths land together, and the residual colour error drops to the point where it stops being visible at normal magnifications. The glass type in the centre element governs how well that works: extra-low-dispersion glass bends the different colours by more nearly the same amount, so less correction has to be forced by the surface curvatures. FCD100 is one of the higher-performing ED types HOYA produces, and it is what this tube is named for.\u003c\/p\u003e\n\u003cp\u003eAir-spacing the elements, rather than cementing them, matters more as lenses get larger. A cemented joint in a 127mm lens is a thick layer of adhesive that expands and contracts with temperature at a different rate to the glass around it. Separating the elements removes that layer, adds two more optical surfaces the designer can shape, and lets the lens reach thermal equilibrium more predictably on a cooling night.\u003c\/p\u003e\n\u003cp\u003eExplore Scientific does not publish a corrected image circle or a backfocus distance for this tube, so those rows are absent from the specifications rather than estimated. If you are planning an imaging train around a specific camera and flattener, send us the parts you have in mind and we will work the spacing out with you before you order.\u003c\/p\u003e\n\u003ch3\u003e\u003cstrong\u003eRecommended Uses\u003c\/strong\u003e\u003c\/h3\u003e\n\u003cul\u003e\n\u003cli\u003eDeep-sky astrophotography of galaxies, globular clusters and small to medium emission nebulae at 952mm.\u003c\/li\u003e\n\u003cli\u003eHigh-power visual observing of the Moon, planets and planetary detail where colour correction is the limiting factor.\u003c\/li\u003e\n\u003cli\u003eDouble-star work near the published .9 arcsec resolution.\u003c\/li\u003e\n\u003cli\u003ePortable dark-site sessions where the 14 lb tube weight and 33.25″ retracted length are what make the trip practical.\u003c\/li\u003e\n\u003cli\u003eLunar and planetary imaging with a focal extender in the train.\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003ch3\u003e\u003cstrong\u003eCompatibility and Accessory Notes\u003c\/strong\u003e\u003c\/h3\u003e\n\u003cul\u003e\n\u003cli\u003e\n\u003cstrong\u003eMount:\u003c\/strong\u003e not included. The published tube weight of 14 lb is before rings, dovetail hardware, diagonal, finder and camera. For imaging, a mount rated at roughly twice the loaded tube weight is the usual working rule; for visual use the margin can be smaller.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eDovetail:\u003c\/strong\u003e Vixen pattern, which fits Vixen saddles and dual-fit saddles that take both Vixen and Losmandy plates.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eEyepieces:\u003c\/strong\u003e not included. At 952mm, a 30mm eyepiece gives 32x, a 20mm gives 48x, a 9mm gives 106x and a 5mm gives 190x.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eDiagonal:\u003c\/strong\u003e the 2.5″ focuser takes 2-inch diagonals with the appropriate adapter. We stock dielectric 2-inch diagonals if one is not already in your case.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eImaging train:\u003c\/strong\u003e a field flattener is the normal companion for deep-sky work with any refractor. Since no corrected image circle is published, we will confirm the flattener match against your camera rather than quote a figure.\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003ch3\u003e\u003cstrong\u003eGood to Know Before You Order\u003c\/strong\u003e\u003c\/h3\u003e\n\u003cul\u003e\n\u003cli\u003e\n\u003cstrong\u003eThis is an optical tube assembly, not a complete telescope.\u003c\/strong\u003e A mount, a tripod and at least one eyepiece are needed alongside it. We can quote the whole package together if that is simpler — just tell us what you already own.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eExplore Scientific has published two different outer-diameter figures for this tube\u003c\/strong\u003e — 130mm on the spec sheet supplied with the product and 145mm on the current product page. If the exact figure decides whether a set of rings or a case will fit, ask us and we will confirm it with our Explore Scientific rep before you commit.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eThe 41.75″ length is with the dew shield extended.\u003c\/strong\u003e Retracted it is 33.25″, which is the number to measure a case or a vehicle against.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eNo corrected image circle or backfocus figure is published\u003c\/strong\u003e for this tube, so those rows are left out below rather than filled with an estimate. Send us your camera and intended flattener and we will work out the spacing with you.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eThe 10 lb focuser rating is a real ceiling.\u003c\/strong\u003e A camera, filter wheel, off-axis guider and rotator add up quickly, and staying inside that figure is what keeps the focuser drawtube square to the optical axis. We can total up a proposed train for you if you are close to the limit.\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003ch3\u003e\u003cstrong\u003eFrequently Asked Questions\u003c\/strong\u003e\u003c\/h3\u003e\n\u003cp\u003e\u003cstrong\u003eIs it difficult to set up?\u003c\/strong\u003e\u003c\/p\u003e\n\u003cp\u003eThe telescope itself is simple — a refractor holds its collimation, so once the tube is in the rings and on the mount it is ready. The work is in the mount and the balance: at 14 lb plus accessories it is a comfortable one-person lift, and it goes on easiest with the mount already levelled and the counterweights roughly set.\u003c\/p\u003e\n\u003cp\u003e\u003cstrong\u003eWhat mount will carry it?\u003c\/strong\u003e\u003c\/p\u003e\n\u003cp\u003eFor visual use, a mount rated well above the 14 lb tube weight once rings, diagonal, finder and eyepiece are added. For imaging, more headroom again, because tracking accuracy degrades long before a mount reaches its stated capacity. Tell us which mount you own and we will give you a straight answer on whether it is enough.\u003c\/p\u003e\n\u003cp\u003e\u003cstrong\u003eWill I see colour fringing?\u003c\/strong\u003e\u003c\/p\u003e\n\u003cp\u003eAn air-spaced triplet using FCD100 ED glass is designed specifically to remove it. On Venus, Sirius and the lunar limb at high power an apochromat of this class shows a clean, neutral image where a two-element achromat would show violet.\u003c\/p\u003e\n\u003cp\u003e\u003cstrong\u003eCan I image with it?\u003c\/strong\u003e\u003c\/p\u003e\n\u003cp\u003eYes — that is a large part of what the 2.5″ HEX focuser and its 10 lb capacity are for. A field flattener is the usual addition for deep-sky work, and an equatorial mount with guiding is the other half of the system.\u003c\/p\u003e\n\u003ch3\u003e\u003cstrong\u003eBottom Line\u003c\/strong\u003e\u003c\/h3\u003e\n\u003cp\u003eIn short: a 127mm f\/7.5 air-spaced triplet apochromat with HOYA FCD100 ED glass, a 2.5″ HEX focuser rated to 10 lb, and a carbon fiber tube that keeps the whole assembly at 14 lb with a Vixen dovetail — five inches of apochromatic aperture on a mount that does not have to be enormous. If you are matching it to a mount or building an imaging train around it, send us the parts list and we will confirm the fit with you first.\u003c\/p\u003e","brand":"Explore Scientific","offers":[{"title":"Default Title","offer_id":44013377781871,"sku":"FCD100-127075-CF-01","price":3947.95,"currency_code":"CAD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0686\/0049\/6239\/files\/FCD100_127ED_CF__51061.jpg?v=1766552312"},{"product_id":"sidara-pro-80","title":"Explore Scientific Sidara Pro 80 80mm GoTo Refractor Telescope System","description":"\u003ch3\u003e\u003cstrong\u003eProduct Overview\u003c\/strong\u003e\u003c\/h3\u003e\n\u003cp\u003eThe Explore Scientific Sidara Pro 80 is a complete telescope system: an 80mm refractor supplied on a computerized GoTo mount that runs Explore Scientific's SkyAssist interface, together with a tripod and a set of eyepieces and accessories. It carries item number ES-AR80900-SAGT-ST10.\u003c\/p\u003e\n\u003cp\u003eExplore Scientific describes the optics as delivering sharp, high-contrast views that suit the Moon and the planets particularly well — which is what an 80mm refractor is good at. A refractor has no central obstruction in the light path, so contrast on fine low-contrast detail such as the Jovian belts or the ridges along a lunar terminator holds up better than in a reflector of similar aperture. Eighty millimetres of aperture gathers roughly 130 times the light of a dark-adapted 7mm eye pupil, and Dawes' criterion for an 80mm objective works out to about 1.45 arcseconds. Those two figures are calculated from the published aperture, and they define what the instrument can show before any question of mounting or software comes into it.\u003c\/p\u003e\n\u003cp\u003eThe GoTo mount is the other half of the system. SkyAssist is Explore Scientific's software interface for driving the mount to a chosen object, which shifts the work of an observing session away from chart-reading and toward looking through the eyepiece. Explore Scientific has not published a specification table for the Sidara Pro 80, so focal length, focal ratio, tripod height, mount payload and the focal lengths of the supplied eyepieces are absent from the specifications below rather than estimated.\u003c\/p\u003e\n\n\u003ch3\u003e\u003cstrong\u003eWho It's For\u003c\/strong\u003e\u003c\/h3\u003e\n\u003cul\u003e\n\u003cli\u003e\n\u003cstrong\u003eObservers who want one box that covers everything.\u003c\/strong\u003e This is a good match if you would rather have telescope, mount, tripod and eyepieces arrive matched to each other than assemble a system piece by piece.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eLunar and planetary observers:\u003c\/strong\u003e an unobstructed 80mm objective is a contrast-friendly design, and the Moon and the bright planets are the targets it serves best from a suburban sky.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eAnyone observing from a light-polluted location:\u003c\/strong\u003e a GoTo mount finds objects that are invisible to the naked eye, which is exactly the situation where star-hopping from anchor stars stops working.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eHouseholds sharing a telescope:\u003c\/strong\u003e a driven mount keeps the target centred while several people take turns at the eyepiece, instead of the object drifting out between looks.\u003c\/li\u003e\n\u003c\/ul\u003e\n\n\u003ch3\u003e\u003cstrong\u003eKey Features \u0026amp; Design\u003c\/strong\u003e\u003c\/h3\u003e\n\u003cul\u003e\n\u003cli\u003e\n\u003cstrong\u003e80mm refractor objective:\u003c\/strong\u003e around 130x the light grasp of the unaided eye, with a theoretical resolution near 1.45 arcseconds.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eUnobstructed optical path:\u003c\/strong\u003e no secondary mirror sitting in the beam, which is the structural reason refractors hold contrast well at moderate aperture.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eComputerized GoTo mount:\u003c\/strong\u003e the mount drives to a selected object and then tracks it, keeping the target in the eyepiece rather than letting the Earth's rotation carry it out.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eSkyAssist interface:\u003c\/strong\u003e Explore Scientific's software front end for object selection and slewing.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eTripod, eyepieces and accessories included:\u003c\/strong\u003e Explore Scientific list all three as part of the package, though the eyepiece focal lengths are not stated on their page.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eNo collimation to maintain:\u003c\/strong\u003e a refractor objective is set at the factory and holds its alignment, so there is no optical adjustment to learn.\u003c\/li\u003e\n\u003c\/ul\u003e\n\n\u003ch3\u003e\u003cstrong\u003eOptical Design\u003c\/strong\u003e\u003c\/h3\u003e\n\u003cp\u003eA refractor forms its image with a lens at the front of the tube rather than a mirror at the back. Light passes straight through the objective to a focus near the rear, with nothing intruding into the beam — no secondary mirror, no spider vanes, and therefore none of the diffraction effects those introduce. The practical consequence is that the contrast transfer at middle spatial frequencies, which is where planetary surface detail lives, stays higher in an unobstructed design than in an obstructed one of the same aperture.\u003c\/p\u003e\n\u003cp\u003eThe second consequence is mechanical. The objective sits in a cell at the front and never needs attention: no collimation routine, no mirror to clean, and a sealed tube that keeps dust off the optical surfaces. Cooldown is brief too, because a thin lens reaches ambient temperature far faster than a thick mirror blank.\u003c\/p\u003e\n\u003cp\u003eExplore Scientific has not published the focal length or focal ratio for the Sidara Pro 80, so the true field of view, the magnification with the supplied eyepieces and the exit pupil at each of them all remain open. Those follow directly from the focal length, and we would rather obtain the figure from Explore Scientific than infer one.\u003c\/p\u003e\n\n\u003ch3\u003e\u003cstrong\u003eRecommended Uses\u003c\/strong\u003e\u003c\/h3\u003e\n\u003cul\u003e\n\u003cli\u003eLunar observing, from the whole disc at low power down to individual craters along the terminator.\u003c\/li\u003e\n\u003cli\u003ePlanetary observing — the phases of Venus, the Galilean moons, the belts of Jupiter and the rings of Saturn.\u003c\/li\u003e\n\u003cli\u003eBright deep-sky targets such as the Orion Nebula, the Pleiades and the brighter double stars.\u003c\/li\u003e\n\u003cli\u003eGuided observing sessions where the mount does the finding and the observer does the looking.\u003c\/li\u003e\n\u003c\/ul\u003e\n\n\u003ch3\u003e\u003cstrong\u003eCompatibility and Accessory Notes\u003c\/strong\u003e\u003c\/h3\u003e\n\u003cul\u003e\n\u003cli\u003e\n\u003cstrong\u003eEyepieces:\u003c\/strong\u003e the package includes eyepieces, and the focal lengths are not stated by Explore Scientific. Once we know what ships in the box, we can advise which additional focal length would widen the useful range most.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eMagnification arithmetic:\u003c\/strong\u003e magnification is the telescope's focal length divided by the eyepiece focal length. The focal length for this model is unpublished, so example magnifications would be invented rather than calculated — we can get the figure from Explore Scientific if it is important to your choice of eyepieces.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eFilters:\u003c\/strong\u003e a lunar or neutral-density filter takes the glare off a bright Moon at higher powers. These thread into the eyepiece barrel, so the barrel size of the supplied eyepieces determines which filters fit.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003ePower:\u003c\/strong\u003e a computerized mount needs a power source, and the supply arrangement is not detailed on the vendor page. A 12 V field battery is the usual answer for observing away from an outlet, and we stock them.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eSolar observing:\u003c\/strong\u003e possible only with a purpose-made front-mounted solar filter sized to the tube's outside diameter, which is a separate purchase.\u003c\/li\u003e\n\u003c\/ul\u003e\n\n\u003ch3\u003e\u003cstrong\u003eGood to Know Before You Order\u003c\/strong\u003e\u003c\/h3\u003e\n\u003cul\u003e\n\u003cli\u003e\n\u003cstrong\u003eExplore Scientific has not published a specification table for the Sidara Pro 80.\u003c\/strong\u003e Focal length, focal ratio, tripod height, mount payload rating, power requirement and the focal lengths of the supplied eyepieces are absent from their page, so those rows are blank here rather than filled with figures from a similar model. If one of them decides the purchase for you, we will get it from our Explore Scientific rep and pass on their answer.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eExplore Scientific currently lists this model as coming soon.\u003c\/strong\u003e Availability timing depends on their release schedule rather than ours, so a note to us before you order will get you the current status and an expected date.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eEighty millimetres has a ceiling.\u003c\/strong\u003e Faint galaxies and small planetary nebulae are aperture-limited targets, and this system is built around the Moon, the planets and the brighter deep-sky objects. Within that range it does very well, and it stays a telescope that actually gets carried outside.\u003c\/li\u003e\n\u003c\/ul\u003e\n\n\u003ch3\u003e\u003cstrong\u003eFrequently Asked Questions\u003c\/strong\u003e\u003c\/h3\u003e\n\u003cp\u003e\u003cstrong\u003eIs it difficult to set up?\u003c\/strong\u003e\u003c\/p\u003e\n\u003cp\u003eNot particularly. The tripod goes up, the mount head sits on it, the tube goes into the saddle, and the electronics are aligned on one or two bright stars before observing starts. A refractor holds its collimation, so there is no optical adjustment on top of that. The alignment routine is the one part that takes practice, and it becomes a two-minute habit after a couple of sessions.\u003c\/p\u003e\n\u003cp\u003e\u003cstrong\u003eDoes it come with everything I need?\u003c\/strong\u003e\u003c\/p\u003e\n\u003cp\u003eExplore Scientific lists the telescope, the GoTo mount with SkyAssist, the tripod, and eyepieces and accessories as part of the package. They do not itemise the accessories, so we will confirm the exact contents with the distributor before your order ships.\u003c\/p\u003e\n\u003cp\u003e\u003cstrong\u003eWhat can I expect to see?\u003c\/strong\u003e\u003c\/p\u003e\n\u003cp\u003eLunar craters and mountain ranges in detail, the phases of Venus, the four Galilean moons and the main belts of Jupiter, the rings of Saturn, the brighter open clusters and the Orion Nebula. Faint galaxies are beyond what 80mm of aperture will show from most locations.\u003c\/p\u003e\n\u003cp\u003e\u003cstrong\u003eWhat focal length is the telescope?\u003c\/strong\u003e\u003c\/p\u003e\n\u003cp\u003eIt is not published on the Explore Scientific page for this model. We can ask them for the figure and give you the answer they supply rather than an estimate.\u003c\/p\u003e\n\u003cp\u003e\u003cstrong\u003eCan I take photographs with it?\u003c\/strong\u003e\u003c\/p\u003e\n\u003cp\u003eShort exposures of the Moon and the brighter planets are within reach, particularly with a smartphone adapter. Deep-sky imaging asks more of a mount than a visual GoTo head is usually designed to give, and the payload and tracking specifications here are unpublished, so we would look at that with you rather than promise it.\u003c\/p\u003e\n\n\u003ch3\u003e\u003cstrong\u003eBottom Line\u003c\/strong\u003e\u003c\/h3\u003e\n\u003cp\u003eIn short: an 80mm refractor on a computerized GoTo mount with SkyAssist, supplied with tripod, eyepieces and accessories as a single system, aimed squarely at the Moon and the planets. Explore Scientific has not yet published a full specification sheet for it — so if there is a figure you need before deciding, ask us and we will get it from them and tell you exactly what they say.\u003c\/p\u003e","brand":"Explore Scientific","offers":[{"title":"Default Title","offer_id":52950292004975,"sku":"ES-AR80900-SAGT-ST10","price":760.95,"currency_code":"CAD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0686\/0049\/6239\/files\/ES-AR80900-SAGT-ST10_1.webp?v=1776178993"},{"product_id":"sidara-pro-102","title":"Explore Scientific Sidara Pro 102 102mm GoTo Refractor Telescope System","description":"\u003ch3\u003e\u003cstrong\u003eProduct Overview\u003c\/strong\u003e\u003c\/h3\u003e\n\u003cp\u003eThe Explore Scientific Sidara Pro 102 is a complete telescope package rather than an optical tube on its own. It pairs a 102mm refractor with an automated GoTo mount built around Explore Scientific's SkyAssist technology, and ships with the tripod, eyepieces and assorted accessories needed to observe on the first clear night. The mount locates objects and then tracks them, so the object stays centred instead of drifting out of the field while you look.\u003c\/p\u003e\n\u003cp\u003eThe four-inch aperture is the figure that sets what the system can show. A 102mm objective gathers roughly 210 times the light of a fully dark-adapted 7mm eye pupil, which is what puts galaxies, nebulae and globular clusters within reach from a reasonable sky, while a refractor's unobstructed light path keeps planetary and lunar contrast crisp.\u003c\/p\u003e\n\u003cp\u003eExplore Scientific publishes an unusually short specification set for this package. There is no focal length, focal ratio, limiting magnitude, resolution figure, mount payload rating, tripod height or weight on their product page, and the supplied eyepieces are listed as included without their focal lengths being stated. Those rows appear below as unpublished rather than as numbers we have estimated, and the sections that follow work from what is actually published.\u003c\/p\u003e\n\n\u003ch3\u003e\u003cstrong\u003eWho It's For\u003c\/strong\u003e\u003c\/h3\u003e\n\u003cul\u003e\n\u003cli\u003e\n\u003cstrong\u003eObservers who want the telescope pointed for them:\u003c\/strong\u003e SkyAssist handles the finding, which turns a session into looking at objects rather than hunting for them.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003ePeople buying one box:\u003c\/strong\u003e optics, mount, tripod, eyepieces and accessories arrive together and are specified to work with each other, so nothing is left to work out afterwards.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eObservers with limited sky time:\u003c\/strong\u003e this is a good match if your clear nights are short and you would rather spend them observing than star hopping.\u003c\/li\u003e\n\u003c\/ul\u003e\n\n\u003ch3\u003e\u003cstrong\u003eKey Features \u0026amp; Design\u003c\/strong\u003e\u003c\/h3\u003e\n\u003cul\u003e\n\u003cli\u003e\n\u003cstrong\u003e102mm refractor optical tube:\u003c\/strong\u003e four inches of unobstructed aperture, with no central obstruction to reduce contrast and no mirrors to collimate.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eAutomated GoTo mount with SkyAssist:\u003c\/strong\u003e the mount drives to a chosen object and then tracks it, taking the Earth's rotation out of the equation.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eTripod included,\u003c\/strong\u003e so the package stands on its own without a separate purchase.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eEyepieces and assorted accessories included,\u003c\/strong\u003e giving a working magnification range out of the box.\u003c\/li\u003e\n\u003c\/ul\u003e\n\n\u003ch3\u003e\u003cstrong\u003eOptical Design\u003c\/strong\u003e\u003c\/h3\u003e\n\u003cp\u003eA refractor forms its image with a lens at the front of the tube rather than a mirror at the back. Light passes straight through the objective to a focus near the eyepiece end, with nothing in the middle of the beam. That unobstructed path is the reason refractors are known for contrast: there is no secondary mirror or spider vane to scatter light out of the diffraction core and into the surrounding rings, so fine low-contrast detail on a planet or the Moon holds up well relative to aperture.\u003c\/p\u003e\n\u003cp\u003eAperture governs two things independently. Light grasp scales with the area of the objective, so 102mm collects about 210 times what a dark-adapted eye does, which is what determines how faint an object can be and still register. Resolving power scales with the diameter, setting how finely two close stars or two adjacent features on Jupiter can be separated. Explore Scientific does not publish a resolution or limiting magnitude figure for this package, so we quote neither and describe the behaviour instead.\u003c\/p\u003e\n\u003cp\u003eExplore Scientific also does not publish the focal length or focal ratio of the Sidara Pro 102's optical tube, and those two figures are what set the magnification the supplied eyepieces deliver and how wide the resulting field is. Rather than infer them, we would rather find out: if the exact focal length is the deciding factor for you, ask us and we will put the question to our Explore Scientific representative before you order.\u003c\/p\u003e\n\n\u003ch3\u003e\u003cstrong\u003eRecommended Uses\u003c\/strong\u003e\u003c\/h3\u003e\n\u003cul\u003e\n\u003cli\u003eGuided tours of the night sky, where the mount finds the object and you concentrate on looking at it.\u003c\/li\u003e\n\u003cli\u003eLunar and planetary observing, where a refractor's contrast and a tracking mount work together at higher magnifications.\u003c\/li\u003e\n\u003cli\u003eBrighter deep-sky objects — open clusters, the larger nebulae, globular clusters and the nearer galaxies.\u003c\/li\u003e\n\u003cli\u003ePublic outreach, school groups and family observing, where tracking keeps a target centred through a queue of viewers.\u003c\/li\u003e\n\u003c\/ul\u003e\n\n\u003ch3\u003e\u003cstrong\u003eCompatibility and Accessory Notes\u003c\/strong\u003e\u003c\/h3\u003e\n\u003cul\u003e\n\u003cli\u003e\n\u003cstrong\u003eEverything needed to observe is in the package:\u003c\/strong\u003e optical tube, GoTo mount, tripod, eyepieces and accessories. No separate mount purchase is involved.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eEyepieces:\u003c\/strong\u003e supplied, though Explore Scientific does not publish which focal lengths ship in the box. Once you have the telescope, the focal lengths are printed on the eyepieces themselves and we can advise on what would usefully extend the set.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eMagnification:\u003c\/strong\u003e telescope focal length divided by eyepiece focal length. Since the focal length of this tube is not published, we are not going to quote magnification figures — ask us and we will get the number from Explore Scientific.\u003c\/li\u003e\n\u003c\/ul\u003e\n\n\u003ch3\u003e\u003cstrong\u003eGood to Know Before You Order\u003c\/strong\u003e\u003c\/h3\u003e\n\u003cul\u003e\n\u003cli\u003e\n\u003cstrong\u003eExplore Scientific publishes very little numerical specification for this package.\u003c\/strong\u003e Focal length, focal ratio, limiting magnitude, resolution, mount capacity, tripod height and total weight are all absent from their product page, so those rows below read as unpublished rather than carrying estimates. If a specific figure decides the purchase for you, ask and we will get it from our Explore Scientific rep first.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eA GoTo mount needs an alignment at the start of each session.\u003c\/strong\u003e That is normally a matter of levelling the tripod and centring one or more bright stars when prompted, and it takes a few minutes. Once done, the mount finds objects for the rest of the night.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eThe supplied eyepiece focal lengths are not published.\u003c\/strong\u003e They are marked on the eyepieces when the package arrives, and if the set turns out to leave a gap at high or low power, we can fill it.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eFour inches of aperture is four inches.\u003c\/strong\u003e A GoTo mount changes how easily you find an object, not how bright it appears; galaxies stay faint grey smudges in any telescope of this size, while clusters, the Moon and the planets are where the view rewards most.\u003c\/li\u003e\n\u003c\/ul\u003e\n\n\u003ch3\u003e\u003cstrong\u003eFrequently Asked Questions\u003c\/strong\u003e\u003c\/h3\u003e\n\u003cp\u003e\u003cstrong\u003eIs it difficult to set up?\u003c\/strong\u003e\u003c\/p\u003e\n\u003cp\u003eThe mechanical side is simple: the tripod is spread and levelled, the mount goes on top, the optical tube seats on the mount and the accessories go on. The part that is new to most people is the alignment routine, where the mount asks you to centre a bright star or two so it can work out where it is pointing. It is a guided process through the hand controller and takes a few minutes once you have done it once. We are happy to walk you through the first alignment over the phone.\u003c\/p\u003e\n\u003cp\u003e\u003cstrong\u003eWhat does SkyAssist do?\u003c\/strong\u003e\u003c\/p\u003e\n\u003cp\u003eIt is the technology behind the mount's automated pointing: you select an object and the mount slews to it and then tracks it, keeping it in the eyepiece rather than letting the Earth's rotation carry it out of the field.\u003c\/p\u003e\n\u003cp\u003e\u003cstrong\u003eWhat magnification will I get?\u003c\/strong\u003e\u003c\/p\u003e\n\u003cp\u003eMagnification is the telescope's focal length divided by the eyepiece's. Explore Scientific does not publish the focal length for this tube, so we would rather ask them than quote a number we cannot source. Send us a message and we will chase it down.\u003c\/p\u003e\n\u003cp\u003e\u003cstrong\u003eWhat can I expect to see?\u003c\/strong\u003e\u003c\/p\u003e\n\u003cp\u003eLunar craters and mountain shadows in real detail, Saturn's rings, the four Galilean moons of Jupiter and its main cloud belts, the phases of Venus, bright double stars, open clusters, the brighter nebulae and globular clusters, and the nearer galaxies as soft grey shapes. Sky darkness affects the deep-sky end far more than the Solar System end.\u003c\/p\u003e\n\n\u003ch3\u003e\u003cstrong\u003eBottom Line\u003c\/strong\u003e\u003c\/h3\u003e\n\u003cp\u003eIn short: a complete 102mm refractor system on an automated SkyAssist GoTo mount, supplied with tripod, eyepieces and accessories, aimed at observers who would rather look at objects than search for them. Explore Scientific publishes little in the way of numerical specifications for it, so if a particular figure matters to your decision, ask us and we will get the answer from our Explore Scientific rep before you order.\u003c\/p\u003e","brand":"Explore Scientific","offers":[{"title":"Default Title","offer_id":52950317662319,"sku":"ES-AR102660-SAGT-ST10","price":1014.95,"currency_code":"CAD","in_stock":true}]},{"product_id":"explore-scientific-ed80-essential-triplet-refractor-0-8x-focal-reducer","title":"Explore Scientific ED80 Essential Series 80mm f\/6 Air-Spaced Triplet Refractor with 0.8x Focal Reducer","description":"\u003ch2\u003eProduct Overview\u003c\/h2\u003e\u003cp\u003eThe Explore Scientific ED80 Essential Series is an 80 mm f\/6 air-spaced apochromatic triplet refractor built around a HOYA FCD-1 extra-low-dispersion element. At 480 mm of focal length and 5.95 lb for the tube assembly, it is a short, portable instrument that works equally well as a visual grab-and-go scope and as an imaging telescope. This configuration ships with the Explore Scientific 0.8x focal reducer, which shortens the system to 384 mm at f\/4.8 for wide-field astrophotography.\u003c\/p\u003e\u003ch2\u003eWho It's For\u003c\/h2\u003e\u003cp\u003eThis is a good fit for an observer who wants apochromatic colour correction without a large tube to carry, and for imagers working with wide targets — large emission nebulae, open clusters, and the Milky Way star fields — where a fast focal ratio matters more than raw aperture. It suits a first dedicated astrophotography telescope, and it remains useful as a guide scope or travel scope after a larger instrument arrives.\u003c\/p\u003e\u003ch2\u003eKey Features \u0026amp; Design\u003c\/h2\u003e\u003cul\u003e\n\u003cli\u003eHOYA FCD-1 ED glass in a true air-spaced triplet objective for colour-accurate, high-contrast images\u003c\/li\u003e\n\u003cli\u003eIncluded 0.8x focal reducer produces an f\/4.8 system for fast wide-field imaging\u003c\/li\u003e\n\u003cli\u003e2.5-inch hexagonal rack-and-pinion focuser rated to carry 10 lb of imaging equipment\u003c\/li\u003e\n\u003cli\u003e99% reflective 2-inch dielectric diagonal included for visual use\u003c\/li\u003e\n\u003cli\u003eTwo focuser extension tubes for reaching focus across a range of eyepiece and camera combinations\u003c\/li\u003e\n\u003cli\u003eBuilt-in retractable dew shield and Hybrid 2N1 finder base installed on the tube\u003c\/li\u003e\n\u003c\/ul\u003e\u003ch2\u003eOptical and Mechanical Design\u003c\/h2\u003e\u003cp\u003eThe objective is a three-element air-spaced design; the ED element suppresses the residual violet and blue halo that a doublet leaves around bright stars, which is what makes the difference visible on the Moon, on planets, and at the edges of a long exposure. Resolution is 1.45 arcseconds and limiting magnitude is 12. The tube measures 18.5 inches with the dew shield extended and 15 inches retracted, with an 85 mm outer diameter, and rides on a Vixen-style dovetail.\u003c\/p\u003e\u003ch2\u003eRecommended Uses\u003c\/h2\u003e\u003cul\u003e\n\u003cli\u003eWide-field deep-sky astrophotography at f\/4.8 with the reducer fitted\u003c\/li\u003e\n\u003cli\u003eVisual observing of the Moon, planets, double stars, and bright deep-sky objects with the 2-inch diagonal fitted\u003c\/li\u003e\n\u003cli\u003eTravel and dark-site trips where tube weight and length are the limiting factor\u003c\/li\u003e\n\u003cli\u003eSolar imaging with an appropriate full-aperture solar filter, sold separately\u003c\/li\u003e\n\u003c\/ul\u003e\u003ch2\u003eCompatibility and Accessory Notes\u003c\/h2\u003e\u003cp\u003eThe Vixen-style dovetail fits the great majority of equatorial and alt-azimuth mounts we carry, including the Explore Scientific iEXOS-100-2 and EXOS-2GT. The reducer's camera-side adapter plate carries a 42 mm T2 thread, so a T2-mount camera ring for your camera body completes the imaging train; the reducer barrel is also threaded for standard 2-inch filters. The Hybrid 2N1 base is installed and ready for a finder scope, which is not included.\u003c\/p\u003e\u003ch2\u003eGood to Know Before You Order\u003c\/h2\u003e\u003cp\u003eThis is an optical tube assembly with a corrector — a mount and tripod are needed and are sold separately. No eyepieces or finder scope are included, so plan on at least one eyepiece for visual use. Explore Scientific publishes a tube weight of 5.95 lb; the shipping weight shown at checkout is rounded up to the next whole pound, and does not change the specification above.\u003c\/p\u003e\u003ch2\u003eFrequently Asked Questions\u003c\/h2\u003e\u003cp\u003e\u003cstrong\u003eIs it difficult to set up?\u003c\/strong\u003e No. The dovetail drops straight into a standard Vixen saddle, the dew shield slides out by hand, and the reducer threads on with the supplied adapter. There are no collimation adjustments to make.\u003c\/p\u003e\u003cp\u003e\u003cstrong\u003eCan I use it visually as well as for imaging?\u003c\/strong\u003e Yes. Fit the included 2-inch diagonal and an eyepiece for visual work, or remove the diagonal and thread on the reducer for imaging.\u003c\/p\u003e\u003cp\u003e\u003cstrong\u003eWhat mount does it need?\u003c\/strong\u003e Any mount rated comfortably above the tube's 5.95 lb plus your camera or diagonal and eyepiece. The iEXOS-100-2 is a common pairing.\u003c\/p\u003e\u003cp\u003e\u003cstrong\u003eWhat is the difference between this and the FCD-100 version?\u003c\/strong\u003e The FCD-100 uses a higher-grade HOYA ED glass and a heavier tube at 7.5 lb. Both are 80 mm f\/6 triplets; the FCD-100 offers a further reduction in residual colour.\u003c\/p\u003e\u003ch2\u003eBottom Line\u003c\/h2\u003e\u003cp\u003eAn 80 mm apochromatic triplet with the reducer already in the box, light enough for a small mount and corrected well enough for long exposures. If you want one telescope that images wide fields at f\/4.8 and still gives clean high-power views, this is a straightforward choice. Our team in Bolton is happy to help match it to a mount.\u003c\/p\u003e","brand":"Explore Scientific","offers":[{"title":"Default Title","offer_id":53955232235631,"sku":"ES-ED-0806-FR0.8x","price":1099.95,"currency_code":"CAD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0686\/0049\/6239\/files\/DSC09065_NoDiag.jpg?v=1785950897"},{"product_id":"explore-scientific-ed80-fcd100-triplet-refractor-0-8x-focal-reducer","title":"Explore Scientific ED80-FCD100 80mm f\/6 Air-Spaced Triplet Refractor with 0.8x Focal Reducer","description":"\u003ch2\u003eProduct Overview\u003c\/h2\u003e\u003cp\u003eThe Explore Scientific ED80-FCD100 is an 80 mm f\/6 air-spaced apochromatic triplet refractor using HOYA FCD-100 extra-low-dispersion glass, the higher grade in Explore Scientific's ED line. Focal length is 480 mm and the tube assembly weighs 7.5 lb. This configuration includes the Explore Scientific 0.8x focal reducer, which brings the working system to f\/4.8 for wide-field imaging.\u003c\/p\u003e\u003ch2\u003eWho It's For\u003c\/h2\u003e\u003cp\u003eThis suits an imager who wants the strongest colour correction available in a compact 80 mm tube, and an observer who values a clean, halo-free view on the Moon, planets, and bright double stars. Compared with the Essential Series version of the same optical layout, the FCD-100 glass reduces residual colour further; it is the choice when the telescope will be doing serious long-exposure work rather than occasional imaging.\u003c\/p\u003e\u003ch2\u003eKey Features \u0026amp; Design\u003c\/h2\u003e\u003cul\u003e\n\u003cli\u003eHOYA FCD-100 ED glass in an air-spaced triplet objective — Explore Scientific's premium ED substrate\u003c\/li\u003e\n\u003cli\u003eIncluded 0.8x focal reducer yields an f\/4.8 imaging system\u003c\/li\u003e\n\u003cli\u003e2.5-inch hexagonal rack-and-pinion focuser rated for 10 lb of imaging equipment\u003c\/li\u003e\n\u003cli\u003e99% reflective 2-inch dielectric diagonal included for visual use\u003c\/li\u003e\n\u003cli\u003eTwo focuser extension tubes to reach focus with varied eyepiece and camera trains\u003c\/li\u003e\n\u003cli\u003eRetractable dew shield and Hybrid 2N1 finder base fitted to the tube\u003c\/li\u003e\n\u003c\/ul\u003e\u003ch2\u003eOptical and Mechanical Design\u003c\/h2\u003e\u003cp\u003eThree air-spaced elements, one of them FCD-100 ED glass, hold chromatic aberration low enough that bright stars record as points rather than as blue-fringed discs. Resolution is 1.45 arcseconds and limiting magnitude is 12. The tube is 18.5 inches long with the dew shield out and 15 inches retracted, 85 mm in diameter, on a Vixen-style dovetail. At 7.5 lb it is heavier than the Essential Series tube, which is worth accounting for when sizing a mount.\u003c\/p\u003e\u003ch2\u003eRecommended Uses\u003c\/h2\u003e\u003cul\u003e\n\u003cli\u003eLong-exposure deep-sky imaging of nebulae, galaxies, and clusters at f\/4.8\u003c\/li\u003e\n\u003cli\u003eHigh-contrast visual observing of the Moon, planets, and double stars\u003c\/li\u003e\n\u003cli\u003eNarrowband imaging, where the flat, well-corrected field pays off across the frame\u003c\/li\u003e\n\u003cli\u003ePortable dark-site setups that still need apochromatic performance\u003c\/li\u003e\n\u003c\/ul\u003e\u003ch2\u003eCompatibility and Accessory Notes\u003c\/h2\u003e\u003cp\u003eThe Vixen-style dovetail fits standard Vixen saddles, including the Explore Scientific iEXOS-100-2 and EXOS-2GT. The reducer presents a 42 mm T2 thread on the camera side, so add the T2 camera ring that matches your body; its barrel also takes standard 2-inch filters. The Hybrid 2N1 base accepts an Explore Scientific finder scope, sold separately.\u003c\/p\u003e\u003ch2\u003eGood to Know Before You Order\u003c\/h2\u003e\u003cp\u003eThis is an optical tube with a reducer — mount, tripod, eyepieces, and finder scope are separate purchases. Explore Scientific publishes a 7.5 lb tube weight; the checkout shipping weight is rounded up to the next whole pound and does not alter the specification. Explore Scientific does not publish a separate weight for the reducer, so the shipping figure covers the tube and packaging.\u003c\/p\u003e\u003ch2\u003eFrequently Asked Questions\u003c\/h2\u003e\u003cp\u003e\u003cstrong\u003eIs it difficult to set up?\u003c\/strong\u003e No. The dovetail seats in a Vixen saddle, the dew shield pulls out by hand, and the reducer threads on with the supplied adapter. Nothing requires collimation.\u003c\/p\u003e\u003cp\u003e\u003cstrong\u003eHow is this different from the ED80 Essential Series?\u003c\/strong\u003e Same 80 mm f\/6 triplet geometry; this one uses FCD-100 glass instead of FCD-1 and weighs 7.5 lb rather than 5.95 lb. The FCD-100 gives a further reduction in residual colour.\u003c\/p\u003e\u003cp\u003e\u003cstrong\u003eDo I still get a full-aperture visual setup?\u003c\/strong\u003e Yes. Fit the included 2-inch diagonal and an eyepiece; remove it and thread on the reducer when you want to image.\u003c\/p\u003e\u003cp\u003e\u003cstrong\u003eWhat size mount should I plan for?\u003c\/strong\u003e Something rated well above 7.5 lb once a camera or diagonal and eyepiece are added. The iEXOS-100-2 handles it for imaging.\u003c\/p\u003e\u003ch2\u003eBottom Line\u003c\/h2\u003e\u003cp\u003eExplore Scientific's best 80 mm ED glass, with the 0.8x reducer already included so the telescope arrives ready to image at f\/4.8. A compact apochromat that does not compromise on colour correction. Talk to our team in Bolton if you would like help pairing it with a mount.\u003c\/p\u003e","brand":"Explore Scientific","offers":[{"title":"Default Title","offer_id":53955240951919,"sku":"ES-FCD100-0806-FR0.8x","price":1649.95,"currency_code":"CAD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0686\/0049\/6239\/files\/FCD100_80mm_2_Burst_004bc693-2c8f-4f74-a888-29f541afe1bf.jpg?v=1785950965"},{"product_id":"explore-scientific-ed80-fcd100-triplet-refractor-field-flattener","title":"Explore Scientific ED80-FCD100 80mm f\/6 Air-Spaced Triplet Refractor with Field Flattener","description":"\u003ch2\u003eProduct Overview\u003c\/h2\u003e\u003cp\u003eThe Explore Scientific ED80-FCD100 is an 80 mm f\/6 air-spaced apochromatic triplet refractor built with HOYA FCD-100 extra-low-dispersion glass. Focal length is 480 mm and the tube assembly weighs 7.5 lb. This configuration pairs the telescope with the Explore Scientific Field Flattener for f\/5 to f\/7 refractors, which corrects the field curvature that otherwise smears stars toward the corners of a long exposure.\u003c\/p\u003e\u003ch2\u003eWho It's For\u003c\/h2\u003e\u003cp\u003eThis is aimed at the imager who wants flat, round stars across the whole frame at the telescope's native f\/6 rather than a faster reduced focal ratio. Where the 0.8x reducer version trades focal length for speed, this configuration keeps all 480 mm and spends the correction on field flatness — the better choice for larger camera sensors and for anyone who prefers native framing.\u003c\/p\u003e\u003ch2\u003eKey Features \u0026amp; Design\u003c\/h2\u003e\u003cul\u003e\n\u003cli\u003eHOYA FCD-100 ED glass in an air-spaced triplet objective\u003c\/li\u003e\n\u003cli\u003eIncluded field flattener matched to f\/5 through f\/7 refractors for edge-to-edge star sharpness\u003c\/li\u003e\n\u003cli\u003e2.5-inch hexagonal rack-and-pinion focuser rated for 10 lb of imaging equipment\u003c\/li\u003e\n\u003cli\u003e99% reflective 2-inch dielectric diagonal included for visual observing\u003c\/li\u003e\n\u003cli\u003eTwo focuser extension tubes for reaching focus across different trains\u003c\/li\u003e\n\u003cli\u003eRetractable dew shield and Vixen-style dovetail\u003c\/li\u003e\n\u003c\/ul\u003e\u003ch2\u003eOptical and Mechanical Design\u003c\/h2\u003e\u003cp\u003eField curvature grows worse as focal ratio gets faster and as sensors get larger; uncorrected, stars near the frame edge stretch radially into small comet shapes. The field flattener sits in the imaging train ahead of the camera and returns the focal plane to flat, so stars at the corners focus at the same point as those at centre. Resolution is 1.45 arcseconds, limiting magnitude 12. The tube runs 18.5 inches with the dew shield extended, 15 inches retracted, 85 mm in diameter.\u003c\/p\u003e\u003ch2\u003eRecommended Uses\u003c\/h2\u003e\u003cul\u003e\n\u003cli\u003eDeep-sky imaging at native f\/6 with round stars to the frame corners\u003c\/li\u003e\n\u003cli\u003eImaging with APS-C and larger sensors, where field curvature shows most\u003c\/li\u003e\n\u003cli\u003eVisual observing of the Moon, planets, and double stars with the included diagonal\u003c\/li\u003e\n\u003cli\u003eMosaic and multi-panel projects that need consistent star shapes across panels\u003c\/li\u003e\n\u003c\/ul\u003e\u003ch2\u003eCompatibility and Accessory Notes\u003c\/h2\u003e\u003cp\u003eThe flattener is specified for refractors between f\/5 and f\/7, which covers this telescope at f\/6. The Vixen-style dovetail fits standard Vixen saddles including the iEXOS-100-2 and EXOS-2GT. Reaching correct spacing between flattener and sensor is what determines corner performance, so plan on the T-thread adapters and spacers that match your camera; our team can work out the stack for your body. A finder scope is not included.\u003c\/p\u003e\u003ch2\u003eGood to Know Before You Order\u003c\/h2\u003e\u003cp\u003eMount, tripod, eyepieces, camera adapters, and finder scope are separate purchases. Explore Scientific does not publish a \"what's in the box\" list for this configuration, so the included-items detail above reflects the tube and flattener specifications they do publish; contact us if you need the packing list confirmed before ordering. Published tube weight is 7.5 lb, and the shipping weight at checkout is rounded up to the next whole pound.\u003c\/p\u003e\u003ch2\u003eFrequently Asked Questions\u003c\/h2\u003e\u003cp\u003e\u003cstrong\u003eIs it difficult to set up?\u003c\/strong\u003e The telescope itself is simple — dovetail into the saddle, dew shield out by hand. The one job that rewards care is setting flattener-to-sensor spacing, and we can specify the adapters for your camera so it is right the first time.\u003c\/p\u003e\u003cp\u003e\u003cstrong\u003eFlattener or 0.8x reducer — which should I choose?\u003c\/strong\u003e The flattener keeps 480 mm at f\/6 and flattens the field. The reducer shortens to 384 mm at f\/4.8 for shorter exposures and wider framing. Larger sensors and native framing favour the flattener.\u003c\/p\u003e\u003cp\u003e\u003cstrong\u003eCan I observe visually with it?\u003c\/strong\u003e Yes. Fit the included 2-inch diagonal and an eyepiece.\u003c\/p\u003e\u003cp\u003e\u003cstrong\u003eWill it work on a small mount?\u003c\/strong\u003e It needs a mount rated comfortably past 7.5 lb plus camera and accessories. The iEXOS-100-2 is a common pairing.\u003c\/p\u003e\u003ch2\u003eBottom Line\u003c\/h2\u003e\u003cp\u003eAn 80 mm FCD-100 apochromat supplied with the matching field flattener, for imagers who want native focal length and clean stars in the corners. Get in touch and we will spec the spacing for your camera.\u003c\/p\u003e","brand":"Explore Scientific","offers":[{"title":"Default Title","offer_id":53955258548335,"sku":"ES-FCD100-0806-FF","price":1649.95,"currency_code":"CAD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0686\/0049\/6239\/files\/FCD100-0806-02-FF.jpg?v=1785951047"},{"product_id":"es-ed80-essential-refractor-0-8x-reducer-iexos-100-2-package","title":"Explore Scientific ED80 Essential Triplet Refractor with 0.8x Focal Reducer and iEXOS-100-2 PMC-Eight GoTo Mount","description":"\u003ch2\u003eProduct Overview\u003c\/h2\u003e\u003cp\u003eThis package pairs the Explore Scientific ED80 Essential Series 80 mm f\/6 air-spaced triplet refractor with the 0.8x focal reducer and the iEXOS-100-2 PMC-Eight equatorial tracker system. It arrives as a complete imaging setup: apochromatic optics corrected to f\/4.8 by the reducer, on a computerised GoTo mount with WiFi and Bluetooth control, with tripod and counterweights included.\u003c\/p\u003e\u003ch2\u003eWho It's For\u003c\/h2\u003e\u003cp\u003eThis is for someone assembling a first complete astrophotography rig, or an experienced observer who wants a light, portable second setup that tracks. Buying the telescope, corrector, and mount together removes the compatibility guesswork — the dovetail, the saddle, and the payload rating are already matched.\u003c\/p\u003e\u003ch2\u003eKey Features \u0026amp; Design\u003c\/h2\u003e\u003cul\u003e\n\u003cli\u003eED80 Essential Series 80 mm f\/6 air-spaced triplet with HOYA FCD-1 ED glass, 480 mm focal length\u003c\/li\u003e\n\u003cli\u003e0.8x focal reducer bringing the system to f\/4.8 for wide-field imaging\u003c\/li\u003e\n\u003cli\u003eiEXOS-100-2 PMC-Eight GoTo equatorial tracker with built-in WiFi and Bluetooth\u003c\/li\u003e\n\u003cli\u003ePMC-Eight motion control uses an eight-core microcontroller, with CPUs assigned to separate tasks for smoother tracking\u003c\/li\u003e\n\u003cli\u003eFree ExploreStars app for Windows, Android, Amazon Fire, and Apple tablets, plus an ASCOM driver for third-party software\u003c\/li\u003e\n\u003cli\u003e2.5-inch hexadecimal focuser rated to 10 lb, 99% reflective 2-inch diagonal, two extension tubes, and counterweights included\u003c\/li\u003e\n\u003c\/ul\u003e\u003ch2\u003eOptical and Mechanical Design\u003c\/h2\u003e\u003cp\u003eThe triplet objective uses an ED element to suppress the colour fringing a doublet leaves on bright stars, giving 1.45 arcsecond resolution and a limiting magnitude of 12. The mount is a German equatorial design: the head weighs 9.45 lb and the tripod 5.35 lb, with counterweights of 1 kg each. Explore Scientific rates capacity at approximately 9 lb of equipment alone, 15 lb photographic and 19 lb visual once counterweights are counted — comfortable margin over the 5.95 lb tube. The tripod stands 25.5 inches collapsed and reaches 45 inches at full extension with the head fitted.\u003c\/p\u003e\u003ch2\u003eRecommended Uses\u003c\/h2\u003e\u003cul\u003e\n\u003cli\u003eWide-field deep-sky astrophotography at f\/4.8 with tracked exposures\u003c\/li\u003e\n\u003cli\u003eVisual observing with GoTo object location, using the included 2-inch diagonal\u003c\/li\u003e\n\u003cli\u003eTravel to dark sites, where the whole package packs down small\u003c\/li\u003e\n\u003cli\u003eLearning the sky, with the ExploreStars database driving the mount to targets\u003c\/li\u003e\n\u003c\/ul\u003e\u003ch2\u003eCompatibility and Accessory Notes\u003c\/h2\u003e\u003cp\u003eThe telescope's Vixen-style dovetail seats directly in the mount's saddle. The reducer presents a 42 mm T2 thread on the camera side, so add the T2 camera ring matching your body; its barrel also takes standard 2-inch filters. The mount runs from the PMC-Eight system over WiFi, Bluetooth, or wired serial, and works with any ASCOM-compatible planetarium software. A tablet or computer is not included. The Hybrid 2N1 finder base is fitted; a finder scope is separate.\u003c\/p\u003e\u003ch2\u003eGood to Know Before You Order\u003c\/h2\u003e\u003cp\u003eNo eyepieces are included, so budget at least one for visual use, and a tablet or laptop is needed to drive the GoTo system. Power for the PMC-Eight comes from a battery pack or a 12 V DC supply, which we stock separately. On weight: Explore Scientific publishes 5.95 lb for the tube, 9.45 lb for the mount head, 5.35 lb for the tripod, and 1 kg per counterweight; they publish no figure for the reducer. The shipping weight shown at checkout is the sum of the published component weights rounded up to the next whole pound, and does not replace the individual specifications above.\u003c\/p\u003e\u003ch2\u003eFrequently Asked Questions\u003c\/h2\u003e\u003cp\u003e\u003cstrong\u003eIs it difficult to set up?\u003c\/strong\u003e The mechanical side is quick — spread the tripod, drop the head on, seat the dovetail, fit the counterweights. The part that takes a first evening is polar alignment and the app's star alignment routine, and Explore Scientific publishes a guide for both. Call us and we will walk you through the first night.\u003c\/p\u003e\u003cp\u003e\u003cstrong\u003eDo I need a computer to use it?\u003c\/strong\u003e Yes, for GoTo. A tablet running the free ExploreStars app is the usual choice; a laptop with ASCOM software also works.\u003c\/p\u003e\u003cp\u003e\u003cstrong\u003eCan I use it visually as well?\u003c\/strong\u003e Yes. Fit the included 2-inch diagonal and an eyepiece, and let the GoTo find targets for you.\u003c\/p\u003e\u003cp\u003e\u003cstrong\u003eWill the mount handle a heavier telescope later?\u003c\/strong\u003e It is rated to roughly 9 lb of equipment, so it will take a modestly larger tube, but it is sized for instruments of about this class.\u003c\/p\u003e\u003ch2\u003eBottom Line\u003c\/h2\u003e\u003cp\u003eA matched telescope, corrector, and tracking mount in one box, ready to image at f\/4.8. Everything mechanical fits together as supplied, so the only decisions left are your camera and an eyepiece. Our team in Bolton can spec both.\u003c\/p\u003e","brand":"Explore Scientific","offers":[{"title":"Default Title","offer_id":53955275456623,"sku":"ES-ED-0806-FR0.8x-IEXOS100","price":1409.95,"currency_code":"CAD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0686\/0049\/6239\/files\/ES-ED0806-FR-iEXOS_1.jpg?v=1785951113"},{"product_id":"es-ed80-fcd100-refractor-0-8x-reducer-iexos-100-2-package","title":"Explore Scientific ED80-FCD100 Triplet Refractor with 0.8x Focal Reducer and iEXOS-100-2 PMC-Eight GoTo Mount","description":"\u003ch2\u003eProduct Overview\u003c\/h2\u003e\u003cp\u003eThis package combines the Explore Scientific ED80-FCD100 80 mm f\/6 air-spaced triplet refractor with the 0.8x focal reducer and the iEXOS-100-2 PMC-Eight equatorial tracker system. The FCD-100 version uses Explore Scientific's premium HOYA ED substrate, and with the reducer fitted the system works at f\/4.8 on a computerised GoTo mount with WiFi and Bluetooth, tripod and counterweights included.\u003c\/p\u003e\u003ch2\u003eWho It's For\u003c\/h2\u003e\u003cp\u003eThis is for the imager who wants the best colour correction available in a compact 80 mm tube and a tracking mount to go with it, in one purchase. Where the Essential Series package is the value option, this one spends the difference on glass — worth it if the rig will be doing regular long-exposure work rather than occasional imaging.\u003c\/p\u003e\u003ch2\u003eKey Features \u0026amp; Design\u003c\/h2\u003e\u003cul\u003e\n\u003cli\u003eED80-FCD100 80 mm f\/6 air-spaced triplet, HOYA FCD-100 ED glass, 480 mm focal length\u003c\/li\u003e\n\u003cli\u003e0.8x focal reducer producing an f\/4.8 imaging system\u003c\/li\u003e\n\u003cli\u003eiEXOS-100-2 PMC-Eight GoTo equatorial tracker with WiFi and Bluetooth\u003c\/li\u003e\n\u003cli\u003eEight-core PMC-Eight motion control with tasks distributed across CPUs for smoother tracking\u003c\/li\u003e\n\u003cli\u003eFree ExploreStars app for Windows, Android, Amazon Fire, and Apple tablets, plus an ASCOM driver\u003c\/li\u003e\n\u003cli\u003e2.5-inch hexagonal focuser rated to 10 lb, 99% reflective 2-inch diagonal, two extension tubes, counterweights\u003c\/li\u003e\n\u003c\/ul\u003e\u003ch2\u003eOptical and Mechanical Design\u003c\/h2\u003e\u003cp\u003eFCD-100 glass in an air-spaced triplet holds residual colour lower than the FCD-1 equivalent, which shows on bright stars and at high power on the Moon and planets. Resolution is 1.45 arcseconds, limiting magnitude 12, and the tube weighs 7.5 lb at 85 mm diameter. The German equatorial mount head weighs 9.45 lb with a 5.35 lb tripod and 1 kg counterweights, rated at approximately 9 lb of equipment alone, 15 lb photographic and 19 lb visual with counterweights counted. The tripod goes from 25.5 inches collapsed to 45 inches extended with the head fitted.\u003c\/p\u003e\u003ch2\u003eRecommended Uses\u003c\/h2\u003e\u003cul\u003e\n\u003cli\u003eTracked deep-sky imaging at f\/4.8 on nebulae, galaxies, and clusters\u003c\/li\u003e\n\u003cli\u003eNarrowband work, where the flat well-corrected field pays across the frame\u003c\/li\u003e\n\u003cli\u003eGoTo-assisted visual observing with the included 2-inch diagonal\u003c\/li\u003e\n\u003cli\u003ePortable dark-site setups that still need apochromatic performance\u003c\/li\u003e\n\u003c\/ul\u003e\u003ch2\u003eCompatibility and Accessory Notes\u003c\/h2\u003e\u003cp\u003eThe Vixen-style dovetail drops into the mount's saddle as supplied. The reducer carries a 42 mm T2 thread on the camera side, so add a T2 ring for your body; the barrel takes standard 2-inch filters. The mount is driven over WiFi, Bluetooth, or wired serial and works with any ASCOM-compatible software; a tablet or computer is not included. The Hybrid 2N1 finder base is fitted and a finder scope is separate.\u003c\/p\u003e\u003ch2\u003eGood to Know Before You Order\u003c\/h2\u003e\u003cp\u003eEyepieces are not included, and a tablet or laptop is needed for GoTo. Power comes from a battery pack or a 12 V DC supply, which we stock. On weight: Explore Scientific publishes 7.5 lb for the tube, 9.45 lb for the mount head, 5.35 lb for the tripod and 1 kg per counterweight, and no figure for the reducer. The checkout shipping weight is the sum of those published figures rounded up to the next whole pound; it does not replace the specifications above.\u003c\/p\u003e\u003ch2\u003eFrequently Asked Questions\u003c\/h2\u003e\u003cp\u003e\u003cstrong\u003eIs it difficult to set up?\u003c\/strong\u003e Assembly is quick. Polar alignment and the app's star alignment take a first evening to learn, and Explore Scientific publishes guides for both. We are happy to talk you through your first night.\u003c\/p\u003e\u003cp\u003e\u003cstrong\u003eFCD-100 or the Essential Series version?\u003c\/strong\u003e Same 80 mm f\/6 triplet geometry. FCD-100 glass reduces residual colour further; the tube is 7.5 lb against 5.95 lb.\u003c\/p\u003e\u003cp\u003e\u003cstrong\u003eDo I need a computer?\u003c\/strong\u003e For GoTo, yes — a tablet running ExploreStars, or a laptop with ASCOM software.\u003c\/p\u003e\u003cp\u003e\u003cstrong\u003eCan I use it visually?\u003c\/strong\u003e Yes, with the included 2-inch diagonal and an eyepiece of your choice.\u003c\/p\u003e\u003ch2\u003eBottom Line\u003c\/h2\u003e\u003cp\u003eExplore Scientific's best 80 mm ED glass, the matching reducer, and a GoTo mount in a single package that images at f\/4.8 out of the box. Add a camera and an eyepiece and it is complete — our team can spec both.\u003c\/p\u003e","brand":"Explore Scientific","offers":[{"title":"Default Title","offer_id":53955284336751,"sku":"ES-FCD100-0806-FR0.8x-IEXOS100","price":2100.95,"currency_code":"CAD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0686\/0049\/6239\/files\/FCD100-0806-FR-iEXOS_1.jpg?v=1785951168"},{"product_id":"es-ed80-fcd100-refractor-field-flattener-iexos-100-2-package","title":"Explore Scientific ED80-FCD100 Triplet Refractor with Field Flattener and iEXOS-100-2 PMC-Eight GoTo Mount","description":"\u003ch2\u003eProduct Overview\u003c\/h2\u003e\u003cp\u003eThis package pairs the Explore Scientific ED80-FCD100 80 mm f\/6 air-spaced triplet refractor with the field flattener for f\/5 to f\/7 refractors and the iEXOS-100-2 PMC-Eight equatorial tracker system. It is a complete imaging setup that works at the telescope's native 480 mm focal length, with the corrector spent on field flatness rather than speed, on a computerised GoTo mount with tripod and counterweights included.\u003c\/p\u003e\u003ch2\u003eWho It's For\u003c\/h2\u003e\u003cp\u003eThis suits an imager using an APS-C or larger sensor, where field curvature shows most plainly, and anyone who prefers native framing to the wider, faster field a reducer gives. It is also a straightforward first complete rig: telescope, corrector, and mount are matched at purchase, so the dovetail, saddle, and payload rating all line up.\u003c\/p\u003e\u003ch2\u003eKey Features \u0026amp; Design\u003c\/h2\u003e\u003cul\u003e\n\u003cli\u003eED80-FCD100 80 mm f\/6 air-spaced triplet, HOYA FCD-100 ED glass, 480 mm focal length\u003c\/li\u003e\n\u003cli\u003eField flattener matched to f\/5 through f\/7 refractors for edge-to-edge star sharpness\u003c\/li\u003e\n\u003cli\u003eiEXOS-100-2 PMC-Eight GoTo equatorial tracker with WiFi and Bluetooth\u003c\/li\u003e\n\u003cli\u003eEight-core PMC-Eight motion control, with CPUs assigned to separate tasks for smoother tracking\u003c\/li\u003e\n\u003cli\u003eFree ExploreStars app for Windows, Android, Amazon Fire, and Apple tablets, plus an ASCOM driver\u003c\/li\u003e\n\u003cli\u003e2.5-inch hexagonal focuser rated to 10 lb, 99% reflective 2-inch diagonal, two extension tubes, counterweights\u003c\/li\u003e\n\u003c\/ul\u003e\u003ch2\u003eOptical and Mechanical Design\u003c\/h2\u003e\u003cp\u003eField curvature makes stars near the frame edge stretch radially into small comet shapes; the flattener sits ahead of the camera and returns the focal plane to flat so corner stars come to focus with the centre. The objective gives 1.45 arcsecond resolution and a limiting magnitude of 12, in a 7.5 lb tube of 85 mm diameter. The mount head weighs 9.45 lb on a 5.35 lb tripod with 1 kg counterweights, rated at approximately 9 lb of equipment alone, 15 lb photographic and 19 lb visual with counterweights. Tripod height runs 25.5 inches collapsed to 45 inches extended with the head fitted.\u003c\/p\u003e\u003ch2\u003eRecommended Uses\u003c\/h2\u003e\u003cul\u003e\n\u003cli\u003eTracked deep-sky imaging at native f\/6 with round stars into the corners\u003c\/li\u003e\n\u003cli\u003eImaging with APS-C and larger sensors\u003c\/li\u003e\n\u003cli\u003eMosaic projects needing consistent star shapes panel to panel\u003c\/li\u003e\n\u003cli\u003eGoTo-assisted visual observing with the included 2-inch diagonal\u003c\/li\u003e\n\u003c\/ul\u003e\u003ch2\u003eCompatibility and Accessory Notes\u003c\/h2\u003e\u003cp\u003eThe flattener is specified for f\/5 to f\/7 refractors, which covers this telescope at f\/6. Corner performance depends on getting the spacing between flattener and sensor right, so plan on the T-thread adapters and spacers that match your camera — we can work the stack out for your body. The Vixen-style dovetail seats in the mount's saddle as supplied. A tablet or computer for GoTo is not included, and a finder scope is separate.\u003c\/p\u003e\u003ch2\u003eGood to Know Before You Order\u003c\/h2\u003e\u003cp\u003eEyepieces, camera adapters, and a tablet or laptop are separate. Power for the PMC-Eight comes from a battery pack or a 12 V DC supply, which we stock. Explore Scientific publishes no packing list for this configuration, so the included items above reflect the tube, flattener, and mount specifications they do publish — ask us if you need it confirmed before ordering. Published weights are 7.5 lb tube, 9.45 lb mount head, 5.35 lb tripod, 1 kg per counterweight; the checkout shipping weight is the sum of those rounded up to the next whole pound.\u003c\/p\u003e\u003ch2\u003eFrequently Asked Questions\u003c\/h2\u003e\u003cp\u003e\u003cstrong\u003eIs it difficult to set up?\u003c\/strong\u003e Assembly is quick. Two things reward care: polar alignment, for which Explore Scientific publishes a guide, and flattener-to-sensor spacing, which we can specify for your camera so it is right first time.\u003c\/p\u003e\u003cp\u003e\u003cstrong\u003eFlattener or 0.8x reducer?\u003c\/strong\u003e The flattener keeps 480 mm at f\/6 and flattens the field; the reducer shortens to 384 mm at f\/4.8 for wider, faster framing. Larger sensors favour the flattener.\u003c\/p\u003e\u003cp\u003e\u003cstrong\u003eDo I need a computer?\u003c\/strong\u003e For GoTo, yes — a tablet running ExploreStars, or a laptop with ASCOM software.\u003c\/p\u003e\u003cp\u003e\u003cstrong\u003eCan I observe visually?\u003c\/strong\u003e Yes, using the included 2-inch diagonal and an eyepiece.\u003c\/p\u003e\u003ch2\u003eBottom Line\u003c\/h2\u003e\u003cp\u003eA premium 80 mm apochromat, its matching flattener, and a GoTo mount together in one package, set up for flat-field imaging at native focal length. Get in touch and we will spec the camera spacing for you.\u003c\/p\u003e","brand":"Explore Scientific","offers":[{"title":"Default Title","offer_id":53955301933167,"sku":"ES-FCD100-0806-FF-IEXOS100","price":2100.95,"currency_code":"CAD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0686\/0049\/6239\/files\/FCD100-0806-FF-IEXOS100.jpg?v=1785951221"},{"product_id":"es-ed102-fcd100-carbon-fiber-refractor-iexos-100-2-package","title":"Explore Scientific ED102-FCD100 102mm f\/7 Carbon Fiber Air-Spaced Triplet Refractor with iEXOS-100-2 PMC-Eight GoTo Mount","description":"\u003ch2\u003eProduct Overview\u003c\/h2\u003e\u003cp\u003eThis package pairs the Explore Scientific ED102-FCD100 with the iEXOS-100-2 PMC-Eight equatorial tracker system. The telescope is a 102 mm f\/7 air-spaced apochromatic triplet using HOYA FCD-100 extra-low-dispersion glass in a carbon fibre tube, at 714 mm focal length and 9.5 lb. It arrives with a computerised GoTo mount, tripod, and counterweights.\u003c\/p\u003e\u003ch2\u003eWho It's For\u003c\/h2\u003e\u003cp\u003eThis is the step up in aperture from the 80 mm triplets while staying genuinely portable — the carbon fibre tube is what makes that possible. It suits an imager who wants more resolution and a longer native focal length for galaxies and planetary nebulae, and a visual observer who wants a 4-inch apochromat that still travels easily.\u003c\/p\u003e\u003ch2\u003eKey Features \u0026amp; Design\u003c\/h2\u003e\u003cul\u003e\n\u003cli\u003e102 mm f\/7 air-spaced triplet with HOYA FCD-100 ED glass, 714 mm focal length\u003c\/li\u003e\n\u003cli\u003eCarbon fibre tube, holding weight to 9.5 lb and reducing focus shift as temperature drops\u003c\/li\u003e\n\u003cli\u003e45 mm wide Vixen-style dovetail plate with cone-angle adjustments\u003c\/li\u003e\n\u003cli\u003eiEXOS-100-2 PMC-Eight GoTo equatorial tracker with WiFi and Bluetooth\u003c\/li\u003e\n\u003cli\u003eEight-core PMC-Eight motion control, tasks distributed across CPUs for smoother tracking\u003c\/li\u003e\n\u003cli\u003eHeavy-duty 2.5-inch HEX focuser rated to carry 10 lb of imaging equipment\u003c\/li\u003e\n\u003c\/ul\u003e\u003ch2\u003eOptical and Mechanical Design\u003c\/h2\u003e\u003cp\u003eA true air-spaced triplet with an FCD-100 element delivers diffraction-limited performance with residual colour low enough that bright stars record without a violet halo across the field. Carbon fibre matters for two reasons: it cuts weight, which is what lets a 4-inch triplet sit on a compact mount, and it expands far less than aluminium as the night cools, so focus holds through a long imaging session. The mount head weighs 9.45 lb on a 5.35 lb tripod with 1 kg counterweights, rated at approximately 9 lb of equipment alone and 15 lb photographic once counterweights are counted. Tripod height runs 25.5 inches collapsed to 45 inches extended with the head fitted.\u003c\/p\u003e\u003ch2\u003eRecommended Uses\u003c\/h2\u003e\u003cul\u003e\n\u003cli\u003eDeep-sky imaging of galaxies, planetary nebulae, and smaller clusters at 714 mm\u003c\/li\u003e\n\u003cli\u003eHigh-resolution lunar and planetary observing and imaging\u003c\/li\u003e\n\u003cli\u003eDouble star work, where the extra aperture separates closer pairs\u003c\/li\u003e\n\u003cli\u003eTravel and dark-site trips needing 4-inch apochromatic performance in a light package\u003c\/li\u003e\n\u003c\/ul\u003e\u003ch2\u003eCompatibility and Accessory Notes\u003c\/h2\u003e\u003cp\u003eThe 45 mm dovetail plate is Vixen-style and seats in the mount's saddle as supplied; the cone-angle adjustments let you square the tube to the mount for accurate GoTo pointing. At f\/7 the telescope falls inside the range of the Explore Scientific field flattener for f\/5 to f\/7 refractors, which we stock separately, and a 0.7x reducer-corrector is also available for it. The mount runs over WiFi, Bluetooth, or wired serial with the ExploreStars app or any ASCOM-compatible software; a tablet or computer is not included.\u003c\/p\u003e\u003ch2\u003eGood to Know Before You Order\u003c\/h2\u003e\u003cp\u003eThe 9.5 lb tube sits close to the mount's 9 lb equipment-only rating, so this pairing is best used with the counterweights fitted as supplied and a modest camera rather than a heavy imaging train — talk to us if you plan to add a filter wheel and off-axis guider. Explore Scientific publishes no packing list for this configuration, so the items above reflect the tube and mount specifications they do publish. Eyepieces, diagonal, camera adapters, and a tablet are separate. Published weights are 9.5 lb tube, 9.45 lb mount head, 5.35 lb tripod, 1 kg per counterweight; the checkout shipping weight is the sum rounded up to the next whole pound.\u003c\/p\u003e\u003ch2\u003eFrequently Asked Questions\u003c\/h2\u003e\u003cp\u003e\u003cstrong\u003eIs it difficult to set up?\u003c\/strong\u003e Mechanically no — the dovetail drops in and the counterweights slide on. Polar alignment and star alignment take a first evening to learn, and Explore Scientific publishes guides for both.\u003c\/p\u003e\u003cp\u003e\u003cstrong\u003eIs the mount big enough for this telescope?\u003c\/strong\u003e It is within rating with the supplied counterweights, and fine for a camera or eyepiece. If you intend to hang a full imaging train off the back, a heavier mount such as the EXOS-2GT is the safer pairing, and we can quote that combination.\u003c\/p\u003e\u003cp\u003e\u003cstrong\u003eWhy carbon fibre?\u003c\/strong\u003e Lower weight and far less focus drift as the temperature falls, which matters over a long exposure sequence.\u003c\/p\u003e\u003cp\u003e\u003cstrong\u003eDo I need a flattener?\u003c\/strong\u003e For imaging with a larger sensor, yes — the f\/5 to f\/7 flattener suits this telescope and we stock it.\u003c\/p\u003e\u003ch2\u003eBottom Line\u003c\/h2\u003e\u003cp\u003eA 4-inch FCD-100 apochromat in a carbon fibre tube with a GoTo mount included, giving longer focal length and more aperture without a heavy setup to carry. Our team in Bolton can advise on the flattener and camera train that suit your sensor.\u003c\/p\u003e","brand":"Explore Scientific","offers":[{"title":"Default Title","offer_id":53955324641391,"sku":"ES-FCD100-102-CF-IEXOS100","price":2819.95,"currency_code":"CAD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0686\/0049\/6239\/files\/cftelebundleesmount.png?v=1785951278"},{"product_id":"explore-scientific-sidara-plus-127-refractor-alt-azimuth-telescope","title":"Explore Scientific Sidara Plus 127mm Refractor Telescope and Alt-Azimuth Mount with Sky Assist","description":"\u003ch2\u003eProduct Overview\u003c\/h2\u003e\n\u003cp\u003eThe Sidara Plus 127 is the largest refractor package in Explore Scientific's Sidara line: a 127 mm objective with an 820 mm focal length, riding on the Sidara Plus alt-azimuth mount with slow-motion controls on both axes, a tripod, and the eyepieces and accessories supplied with the package. Explore Scientific's own description calls it a system that \"gathers a substantial amount of light while maintaining a balanced field of view,\" and lists it under item number ES-AR127820-MAZ01. Working out to roughly f\/6.5, it is the aperture-first choice in the series for someone who wants a refractor rather than a reflector and does not want the tube to be the limiting factor.\u003c\/p\u003e\n\n\u003ch2\u003eWho It's For\u003c\/h2\u003e\n\u003cp\u003eThis is a first telescope for someone who has decided they want a refractor and wants the biggest one in the range, or a gift for someone in that position. Be clear on what a 127 mm aperture actually buys. Against the 90 mm Sidara Nano it collects roughly twice the light, and against a 60 mm department-store scope it collects more than four times as much. In practice that means the Moon at high power is genuinely absorbing, with craters, rilles and shadow detail along the terminator that changes night to night. Saturn's rings will be an unmistakable ring rather than an ambiguous bulge. Jupiter shows its two main cloud belts and the four Galilean moons. Brighter deep sky objects such as the Orion Nebula, the Andromeda Galaxy, the Pleiades and the great cluster in Hercules are within reach from a suburban garden, but they will look like grey, textured mist rather than the colour images you have seen online. No telescope at any price shows those colours to the eye. That is a limit of human night vision, not of this instrument.\u003c\/p\u003e\n\u003cp\u003eRefractor against reflector matters at this size. The refractor here has a sealed tube with no central obstruction, so contrast on the Moon and planets is clean, collimation is not something you will ever have to think about, and there is nothing to align before you observe. The trade-off is that a 127 mm achromatic refractor at this focal ratio shows some violet-blue fringing around very bright objects, most visibly on the limb of the Moon, on Venus and on Jupiter, which the 150 mm Sidara Plus reflector does not. The reflector in turn gives you more aperture for less money but needs occasional collimation and takes longer to cool to outside temperature. If you value low fuss and colour-neutral contrast on the Moon and planets, and you can live with a little fringing on the very brightest targets, the refractor is the more forgiving instrument to own.\u003c\/p\u003e\n\n\u003ch2\u003eKey Features \u0026amp; Design\u003c\/h2\u003e\n\u003cul\u003e\n\u003cli\u003e127 mm aperture refractor with an 820 mm focal length, roughly f\/6.5, and the largest refractor in the Sidara series.\u003c\/li\u003e\n\u003cli\u003eSidara Plus alt-azimuth head with slow-motion controls on both axes for smooth geared tracking rather than nudge-and-hope.\u003c\/li\u003e\n\u003cli\u003eSky Assist target guidance, which Explore Scientific describes as \"helping guide users to celestial targets, reducing time spent searching and increasing time spent observing.\"\u003c\/li\u003e\n\u003cli\u003eSupplied as a complete package: optical tube, mount, tripod, and eyepieces and accessories per the package configuration.\u003c\/li\u003e\n\u003cli\u003eStraightforward up-and-down, left-and-right alt-azimuth motion that matches how a beginner intuitively expects a telescope to move.\u003c\/li\u003e\n\u003cli\u003eUnobstructed refractor light path with no secondary mirror, no diffraction spikes and no collimation routine.\u003c\/li\u003e\n\u003cli\u003eBuilt by Explore Scientific to stay portable enough that it gets carried outside regularly rather than left in a cupboard.\u003c\/li\u003e\n\u003c\/ul\u003e\n\n\u003ch2\u003eOptical and Mechanical Design\u003c\/h2\u003e\n\u003cp\u003eTwo numbers do most of the work here. The 127 mm aperture sets both how much light the telescope collects and how fine a detail it can resolve, and resolving power scales with aperture, so a 127 mm objective separates closer double stars and shows finer lunar features than any smaller tube regardless of which eyepiece you screw into it. The 820 mm focal length then sets the magnification each eyepiece delivers, since magnification is telescope focal length divided by eyepiece focal length: a 25 mm eyepiece gives about 33x for wide, easy sweeping and a 10 mm gives about 82x for the Moon and planets. The useful ceiling for a 127 mm aperture sits somewhere near 250x on a steady night, and atmospheric seeing will usually stop you well below that. Mechanically, an alt-azimuth mount moves in altitude and azimuth rather than following the sky's rotation about a single axis, which makes it far more intuitive to point but means you correct in two directions as an object drifts out of the field. That is precisely what the dual-axis slow-motion controls are for. They let you make small geared corrections at high magnification without knocking the tube off target, which is the difference between usable and infuriating above about 80x.\u003c\/p\u003e\n\n\u003ch2\u003eRecommended Uses\u003c\/h2\u003e\n\u003cul\u003e\n\u003cli\u003eDetailed lunar observing, where the aperture and the unobstructed light path show terminator detail that changes from night to night.\u003c\/li\u003e\n\u003cli\u003ePlanetary viewing: Saturn's rings, Jupiter's belts and moons, the phases of Venus, and Mars around opposition.\u003c\/li\u003e\n\u003cli\u003eBrighter deep sky objects from suburban skies, including open and globular clusters, the Orion Nebula and the brighter galaxies.\u003c\/li\u003e\n\u003cli\u003eSplitting double stars, where the 127 mm aperture's resolving power is the deciding factor.\u003c\/li\u003e\n\u003cli\u003eA first serious telescope for an adult beginner or an older child who wants an instrument they will not outgrow in a season.\u003c\/li\u003e\n\u003c\/ul\u003e\n\n\u003ch2\u003eCompatibility and Accessory Notes\u003c\/h2\u003e\n\u003cp\u003eThe package arrives with eyepieces and accessories per Explore Scientific's package configuration, and that supplied set is a starting point rather than a finished collection. The most worthwhile early additions are a good medium-power eyepiece somewhere in the 8 mm to 12 mm range for planetary work, a neutral density Moon filter to take the glare off a near-full Moon at this aperture, and a comfortable star diagonal if you find yourself craning at objects high overhead. Explore Scientific does not publish the focuser barrel size, the eyepiece specifications, the finder type or the diagonal for this package on its product page, so if you are buying eyepieces or a diagonal to go alongside it, contact our team in Bolton and we will confirm the fitting before you order rather than have you guess. The same applies to whether this tube's dovetail will transfer onto an equatorial mount later, which is genuinely model-dependent and worth checking rather than assuming.\u003c\/p\u003e\n\n\u003ch2\u003eGood to Know Before You Order\u003c\/h2\u003e\n\u003cp\u003eExplore Scientific publishes no shipping weight for this item, so we are confirming it on our own scales before the listing goes live. That is why it is currently unpublished. Contact us and we will give you a shipping figure for your address. Beyond the weight, Explore Scientific's published information on this package is unusually thin. The product page gives the aperture, the focal length, the mount type and the fact that eyepieces and accessories are included, but it does not itemise which eyepieces, which finder or which diagonal ship in the box, and there is no specification table. We are not going to invent those details, so ask us and we will confirm against the carton before you commit. Note too that this is an alt-azimuth mount rather than an equatorial one, and it is not a motorised GoTo mount: pointing and tracking are done by hand using the slow-motion controls. It is not an astrophotography rig, and it will manage casual phone snaps of the Moon and not much more.\u003c\/p\u003e\n\n\u003ch2\u003eFrequently Asked Questions\u003c\/h2\u003e\n\u003cp\u003e\u003cstrong\u003eWhat exactly is Sky Assist, and do I need a phone for it?\u003c\/strong\u003e On this package Explore Scientific describes Sky Assist only as target guidance, in their words \"helping guide users to celestial targets, reducing time spent searching and increasing time spent observing.\" On their motorised Sidara Pro mounts they go further and say that using Sky Assist \"users can select targets and allow the mount to move the telescope into position,\" but the Sidara Plus is a manual mount, so here it is a finding aid rather than something that drives the telescope for you. Explore Scientific has not published the full detail of what the feature requires or how it is set up, and we would rather say that plainly than guess. Contact us and we will confirm the current details with the distributor.\u003c\/p\u003e\n\u003cp\u003e\u003cstrong\u003eWill I see colour in nebulae and galaxies the way photographs show it?\u003c\/strong\u003e No, and no telescope will. The colour receptors in the human eye do not work at low light levels, so deep sky objects appear as grey or grey-green structure regardless of aperture. What more aperture buys you is more of that structure, seen more clearly. The Moon, the planets and stars do show colour.\u003c\/p\u003e\n\u003cp\u003e\u003cstrong\u003eShould I buy this or the 150 mm Sidara Plus reflector?\u003c\/strong\u003e Take the 127 mm refractor if you want clean contrast, no maintenance and no collimation, and you mainly observe the Moon and planets. Take the 150 mm reflector if raw light grasp on faint deep sky objects matters more to you and you do not mind checking collimation from time to time.\u003c\/p\u003e\n\u003cp\u003e\u003cstrong\u003eCan a complete beginner set this up alone?\u003c\/strong\u003e Yes. It is a package designed to go together without tools beyond what is supplied, and the alt-azimuth mount removes the polar alignment step that trips people up on equatorial mounts. Allow one unhurried evening indoors to assemble it and to learn the focuser and finder before you take it out in the dark.\u003c\/p\u003e\n\n\u003ch2\u003eBottom Line\u003c\/h2\u003e\n\u003cp\u003eThe Sidara Plus 127 is the aperture-first refractor in the Sidara range, and it earns that aperture on the Moon, the planets and the brighter deep sky. It asks nothing of you in maintenance and gives you geared slow-motion control where a beginner package usually gives you a stiff pan handle. If you are weighing it against the 150 mm reflector or one of the smaller Sidara packages, contact our team in Bolton and we will talk it through against your skies and your budget.\u003c\/p\u003e","brand":"Explore Scientific","offers":[{"title":"Default Title","offer_id":53958605602927,"sku":"ES-AR127820-MAZ01","price":1141.95,"currency_code":"CAD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0686\/0049\/6239\/files\/sidaraplus127v2.jpg?v=1785960657"},{"product_id":"explore-scientific-sidara-essential-102-refractor-telescope","title":"Explore Scientific Sidara Essential 102mm Refractor Telescope and Alt-Azimuth Mount with Sky Assist","description":"\u003ch2\u003eProduct Overview\u003c\/h2\u003e\n\u003cp\u003eThe Sidara Essential 102 pairs a 102 mm refractor with Explore Scientific's Essential alt-azimuth mount, a tripod, and eyepieces and accessories per the package configuration. Explore Scientific describes the combination as \"a balanced system focused on brightness, versatility, and ease of use,\" with \"smooth slow motion controls and adjustable positioning\" on both axes, and calls it \"an excellent choice for those who want a dependable, all around telescope that is easy to use and capable of delivering consistent results.\" It carries vendor item number ES-AR102660-MAZ01-ST10. A four-inch refractor on a steady alt-azimuth head has been the standard recommendation for a first telescope for decades, and this is Explore Scientific's current version of it.\u003c\/p\u003e\n\n\u003ch2\u003eWho It's For\u003c\/h2\u003e\n\u003cp\u003eThis is the sensible middle of the Sidara range, and probably the most defensible choice if you are buying a first telescope for yourself or as a gift and do not yet know which direction the interest will run. At 102 mm it collects around a third more light than the 90 mm Sidara Nano and about forty per cent less than the 127 mm Sidara Plus, which in practice puts it comfortably past the threshold where a telescope stops being a novelty. Expect the Moon to be the object that converts people, with craters and mountain shadows in real relief. Saturn will clearly show its rings, Jupiter its cloud belts and four moons, Venus its phase. On deep sky objects a four-inch refractor from a suburban garden will show you the Orion Nebula, the Pleiades, the double cluster in Perseus, the brighter globulars as soft round glows, and the Andromeda Galaxy as an elongated smudge. What it will not show is colour in those objects, and no telescope will, because the eye's colour vision simply does not work at that light level. Anyone expecting Hubble images from an eyepiece is going to be disappointed by every telescope ever made, which is worth saying out loud before a gift is unwrapped.\u003c\/p\u003e\n\u003cp\u003eChoosing the refractor over the 130 mm Essential reflector at a similar tier is a trade between convenience and raw aperture. The refractor arrives aligned and stays aligned, has a sealed tube that keeps dust off the optics, and needs no maintenance ritual at all, which matters a great deal if the intended owner is a child, a gift recipient, or anyone who will lose interest if the equipment demands homework. It also has cleaner contrast on the Moon and planets because there is no secondary mirror sitting in the light path. The reflector counters with more aperture for less money and no colour fringing. This 102 mm objective is an achromat, so on the very brightest targets, the limb of a full Moon or Venus low in twilight, you will see a faint violet-blue edge. It is a known characteristic of the design rather than a fault, and most people stop noticing it within a few sessions.\u003c\/p\u003e\n\n\u003ch2\u003eKey Features \u0026amp; Design\u003c\/h2\u003e\n\u003cul\u003e\n\u003cli\u003e102 mm aperture refractor, the classic four-inch size long recommended as a capable first telescope.\u003c\/li\u003e\n\u003cli\u003eEssential alt-azimuth mount with dual-axis slow-motion controls for smooth, geared tracking on both axes.\u003c\/li\u003e\n\u003cli\u003eAdjustable mount positioning, which Explore Scientific highlights for comfortable viewing even on objects high in the sky.\u003c\/li\u003e\n\u003cli\u003eSky Assist compatibility, which Explore Scientific says \"helps users explore the night sky more efficiently.\"\u003c\/li\u003e\n\u003cli\u003eSealed refractor tube with no central obstruction, no diffraction spikes and no collimation to maintain.\u003c\/li\u003e\n\u003cli\u003eSupplied complete: 102 mm refractor tube, Essential mount, tripod, and eyepieces and accessories per the package configuration.\u003c\/li\u003e\n\u003cli\u003ePositioned by Explore Scientific as the all-round choice in the Sidara line rather than a specialist for one kind of target.\u003c\/li\u003e\n\u003c\/ul\u003e\n\n\u003ch2\u003eOptical Design\u003c\/h2\u003e\n\u003cp\u003eAn achromatic refractor of this class uses a two-element objective: a crown glass lens and a flint glass lens of differing dispersion, cemented or air-spaced, chosen so that two wavelengths of light come to focus at the same point. That correction is what makes the image usable, but it is only a correction at two wavelengths, so the far violet end of the spectrum lands slightly out of focus and appears as a soft halo around very bright objects. Aperture governs both light grasp and resolution, and at 102 mm the theoretical resolving limit is a little over one arcsecond, which is enough to split many attractive double stars and to show real texture in lunar terrain. Explore Scientific does not publish a focal length or focal ratio for this package on its product page, describing only a \"moderate focal length\"; the vendor item number ES-AR102660 follows the company's usual convention of encoding aperture and focal length, which would put it at 660 mm and roughly f\/6.5, and that matches the pattern of the other packages in the series. We would rather flag that as a reasonable reading of the item number than present it as a published figure, so contact our team in Bolton and we will confirm it against the carton before you order eyepieces around it.\u003c\/p\u003e\n\n\u003ch2\u003eRecommended Uses\u003c\/h2\u003e\n\u003cul\u003e\n\u003cli\u003eLunar observing, which is where a four-inch refractor makes its strongest first impression.\u003c\/li\u003e\n\u003cli\u003ePlanetary viewing of Saturn, Jupiter, Venus and Mars at moderate to high magnification.\u003c\/li\u003e\n\u003cli\u003eBright deep sky objects from suburban skies: open clusters, the brighter nebulae and the larger globulars.\u003c\/li\u003e\n\u003cli\u003eDaytime terrestrial viewing with an erecting diagonal, which a refractor handles better than a Newtonian.\u003c\/li\u003e\n\u003cli\u003eA first telescope as a gift, where low maintenance and quick setup matter as much as the optical specification.\u003c\/li\u003e\n\u003c\/ul\u003e\n\n\u003ch2\u003eCompatibility and Accessory Notes\u003c\/h2\u003e\n\u003cp\u003eThe package includes eyepieces and accessories, though Explore Scientific does not itemise them on the product page. The additions worth considering first are a higher-power eyepiece around 8 mm to 10 mm for planetary nights, a neutral density Moon filter, and an erecting prism diagonal if terrestrial daytime use is part of the plan. Because the vendor does not publish the focuser barrel size, the finder type or the supplied diagonal for this package, do not order eyepieces or filters on assumption. Contact us and we will confirm whether it takes 1.25-inch or 2-inch fittings before anything ships. The same goes for the Essential mount's stated load capacity and dovetail standard, which Explore Scientific has not published; if you are thinking about putting a different tube on this mount later, or this tube on a different mount, ask us and we will check the specifics rather than guess on your behalf.\u003c\/p\u003e\n\n\u003ch2\u003eGood to Know Before You Order\u003c\/h2\u003e\n\u003cp\u003eExplore Scientific publishes no shipping weight for this item, so we are confirming it on our own scales before the listing goes live. That is why it is currently unpublished. Contact us and we will give you a shipping figure for your address. It is also fair to say that the vendor's published detail on this package is sparse. There is no specification table, no focal length figure, and no itemised accessory list, and where we have inferred a figure above from the item number we have said so rather than dressed it up as a specification. Practically, note that this is a manual mount with no motors and no GoTo function, so you point the telescope yourself and use the slow-motion controls to keep an object in view as the sky drifts. It is not an astrophotography instrument. And as with any telescope, a first evening spent assembling it indoors and aligning the finder in daylight will save a great deal of frustration on the first clear night.\u003c\/p\u003e\n\n\u003ch2\u003eFrequently Asked Questions\u003c\/h2\u003e\n\u003cp\u003e\u003cstrong\u003eWhat is Sky Assist, in plain terms?\u003c\/strong\u003e On this package Explore Scientific describes it only as a way to \"explore the night sky more efficiently,\" and elsewhere in the Sidara line as guidance that helps you find celestial targets and spend less time searching. On their motorised Sidara Pro mounts they say Sky Assist lets users \"select targets and allow the mount to move the telescope into position,\" but this is a manual mount, so here it points you at the target and you move the telescope yourself. Explore Scientific has not published the full requirements or setup process, and we are not going to invent app features on their behalf. Ask us and we will confirm the current details with the distributor.\u003c\/p\u003e\n\u003cp\u003e\u003cstrong\u003eIs 102 mm enough aperture to be worth it?\u003c\/strong\u003e Yes. Four inches is the point at which the Moon, the planets and the brighter deep sky objects all become genuinely rewarding rather than merely visible. More aperture always shows more, but a 102 mm refractor that gets used regularly beats a larger telescope that stays in its box.\u003c\/p\u003e\n\u003cp\u003e\u003cstrong\u003eShould I get this or the 130 mm Essential reflector?\u003c\/strong\u003e Choose this if you want zero maintenance, cleaner planetary contrast, and the option of daytime use. Choose the 130 mm reflector if faint deep sky objects are the draw and you are willing to learn collimation. They sit at similar tiers, so it is genuinely a preference rather than a step up or down.\u003c\/p\u003e\n\u003cp\u003e\u003cstrong\u003eIs it suitable for a child?\u003c\/strong\u003e For a supervised child, yes, and the refractor's lack of collimation is a real advantage there. The tripod and mount are adult-sized, so expect to help with setup and with getting the eyepiece to a comfortable height.\u003c\/p\u003e\n\n\u003ch2\u003eBottom Line\u003c\/h2\u003e\n\u003cp\u003eThe Sidara Essential 102 is the safe, sensible answer in this range: enough aperture to show the things that make people keep observing, and no maintenance to get in the way. If you are choosing between it, the 130 mm reflector and the smaller Nano 90, contact our team in Bolton and we will help you match it to your skies and to who will actually be using it.\u003c\/p\u003e","brand":"Explore Scientific","offers":[{"title":"Default Title","offer_id":53958671237231,"sku":"ES-AR102660-MAZ01-ST10","price":633.95,"currency_code":"CAD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0686\/0049\/6239\/files\/sidara_essential_102_v2.jpg?v=1785960797"},{"product_id":"explore-scientific-sidara-nano-90-refractor-telescope","title":"Explore Scientific Sidara Nano 90mm Refractor Telescope and Alt-Azimuth Mount with Sky Assist","description":"\u003ch2\u003eProduct Overview\u003c\/h2\u003e\n\u003cp\u003eThe Sidara Nano 90 is the entry point to Explore Scientific's Sidara range: a 90 mm refractor of 700 mm focal length, which works out to about f\/7.8, on the compact Nano alt-azimuth mount with a slow-motion control system, a tripod, and eyepieces and accessories. Explore Scientific describes it as \"a compact and highly approachable system\" that gives \"a balanced combination of magnification and clarity,\" and says it is \"well suited for observing the Moon, planets, and brighter deep sky objects, offering sharp and stable views.\" It carries vendor item number ES-AR90700-MAZ-NANO and is the lightest and simplest package in the series.\u003c\/p\u003e\n\n\u003ch2\u003eWho It's For\u003c\/h2\u003e\n\u003cp\u003eThis is the one to buy when portability and simplicity matter more than aperture, and it is the most realistic gift telescope in the range. Ninety millimetres is a genuine, useful aperture rather than a toy: it will show the Moon in real detail, Saturn's rings unmistakably, Jupiter's two main cloud belts and its four bright moons, the phases of Venus, the Orion Nebula, the Pleiades, the double cluster in Perseus, and the brighter globular clusters as soft round glows. That list is enough to keep a curious beginner busy for years. What it will not do is compete on faint deep sky objects. Galaxies beyond the very brightest will be difficult or invisible from a suburban garden, and even under dark skies they are faint grey patches. Nothing at this aperture shows colour in nebulae, because human colour vision does not operate at those light levels, so a gift recipient expecting the images they have seen online needs that expectation adjusted before the box is opened rather than after.\u003c\/p\u003e\n\u003cp\u003eSet against the larger telescopes in this group, the trade is honest and worth understanding. The 102 mm Essential refractor collects about a third more light, and the 150 mm Plus reflector collects nearly three times as much, so each step up genuinely shows more. But light grasp is only half the story for a first telescope. The Nano 90 is the one that is light enough to carry outside on a whim, quick enough to set up that a clear half hour is worth using, and simple enough that nobody has to be taught anything before they look through it. A telescope that gets used every clear week shows its owner far more over a year than a bigger one that stays in a cupboard. There is also a real optical advantage hiding in the specification: at roughly f\/7.8 this is the slowest, most gently corrected refractor in the range, so it shows noticeably less violet fringing on the Moon and on bright planets than the faster 102 mm and 127 mm achromats do. Small aperture, but clean images.\u003c\/p\u003e\n\n\u003ch2\u003eKey Features \u0026amp; Design\u003c\/h2\u003e\n\u003cul\u003e\n\u003cli\u003e90 mm aperture refractor with a 700 mm focal length, giving a relatively slow f\/7.8 system with well-controlled colour error.\u003c\/li\u003e\n\u003cli\u003eCompact Nano alt-azimuth mount with a slow-motion control system for smooth tracking, described by Explore Scientific as \"making it easier to follow objects across the sky.\"\u003c\/li\u003e\n\u003cli\u003eThe lightest and most portable package in the Sidara line, intended to be carried out and set up quickly.\u003c\/li\u003e\n\u003cli\u003eSky Assist compatibility, which Explore Scientific says helps \"guide users to celestial targets, reducing the learning curve and improving the overall experience.\"\u003c\/li\u003e\n\u003cli\u003eSealed refractor tube with no mirrors to align, so there is no collimation and no maintenance routine.\u003c\/li\u003e\n\u003cli\u003eSupplied complete: 90 mm refractor tube, Nano mount, tripod, and eyepieces and accessories.\u003c\/li\u003e\n\u003cli\u003eUsable for daytime terrestrial viewing with an appropriate erecting diagonal, which reflectors cannot manage.\u003c\/li\u003e\n\u003c\/ul\u003e\n\n\u003ch2\u003eOptical Design\u003c\/h2\u003e\n\u003cp\u003eFocal ratio is the quiet hero of this specification. A doublet achromat brings two wavelengths to a common focus and leaves the rest slightly astray, and the size of that residual error shrinks as the telescope gets slower, which is to say as the focal ratio number gets larger. At f\/7.8 the 90 mm objective here is meaningfully better corrected than the faster achromatic refractors elsewhere in the Sidara line, so bright objects show a cleaner edge with less of the violet halo that faster achromats produce. The 700 mm focal length also gives comfortable magnifications without extreme eyepieces: a 25 mm eyepiece yields about 28x for wide, easy views, and a 10 mm yields about 70x, which is a good working power for the Moon and planets. The realistic upper limit for a 90 mm aperture is somewhere around 150x, and atmospheric steadiness rather than the optics will usually be what stops you. Mechanically, the Nano mount moves in altitude and azimuth, the two directions a beginner instinctively expects, and its slow-motion control lets you follow an object as the Earth's rotation carries it out of the field without bumping the tube off target, which is the difference between comfortable viewing and constant re-aiming above about 50x.\u003c\/p\u003e\n\n\u003ch2\u003eRecommended Uses\u003c\/h2\u003e\n\u003cul\u003e\n\u003cli\u003eLunar observing, where 90 mm of clean aperture shows craters, mountain ranges and terminator shadows in detail.\u003c\/li\u003e\n\u003cli\u003ePlanetary viewing of Saturn, Jupiter and Venus at moderate magnification.\u003c\/li\u003e\n\u003cli\u003eBright star clusters and the brighter nebulae from suburban or semi-rural skies.\u003c\/li\u003e\n\u003cli\u003eTravel and grab-and-go observing, including camping trips and cottage weekends where bulk is the deciding factor.\u003c\/li\u003e\n\u003cli\u003eDaytime terrestrial and wildlife viewing with a suitable erecting diagonal.\u003c\/li\u003e\n\u003c\/ul\u003e\n\n\u003ch2\u003eCompatibility and Accessory Notes\u003c\/h2\u003e\n\u003cp\u003eThe package includes eyepieces and accessories, but Explore Scientific does not itemise them, publish the focuser barrel size, or state the finder and diagonal supplied. That matters here more than usual, because a 90 mm refractor is the size where a single good eyepiece changes the experience noticeably. If you want a higher-power eyepiece in the 6 mm to 9 mm range for planetary nights, or an erecting prism for daytime use, contact our team in Bolton and we will confirm whether the focuser takes 1.25-inch fittings before you order anything. A neutral density Moon filter is a modest and worthwhile addition. If you are thinking about whether this tube could later ride on a larger mount, or whether the Nano head could carry a heavier telescope, that is genuinely model-dependent and Explore Scientific has not published a load rating, so ask us and we will check rather than guess.\u003c\/p\u003e\n\n\u003ch2\u003eGood to Know Before You Order\u003c\/h2\u003e\n\u003cp\u003eExplore Scientific publishes no shipping weight for this item, so we are confirming it on our own scales before the listing goes live. That is why it is currently unpublished. Contact us and we will give you a shipping figure for your address. Beyond that, be realistic about the mount rather than the optics. The Nano is the lightest head in the Sidara range and is matched to this small tube; a light mount is easy to carry but will also settle more slowly after you touch the focuser, so expect a second or two of vibration at higher powers. That is normal for a compact package at this size. The vendor publishes no specification table and no itemised accessory list for this telescope, so we are not going to state what is in the box beyond what they say. This is a manual mount with no motors and no GoTo, and it is not intended for astrophotography beyond casual phone shots of the Moon.\u003c\/p\u003e\n\n\u003ch2\u003eFrequently Asked Questions\u003c\/h2\u003e\n\u003cp\u003e\u003cstrong\u003eWhat is Sky Assist and what does it require?\u003c\/strong\u003e Explore Scientific describes it on this package as guidance that helps \"guide users to celestial targets, reducing the learning curve and improving the overall experience.\" On their motorised Sidara Pro mounts they say Sky Assist lets users \"select targets and allow the mount to move the telescope into position,\" but the Nano is a manual mount, so here it points you toward a target and you move the telescope by hand. Explore Scientific has not published what the feature needs in order to run or how it is configured, and we would rather say so than describe features they have not documented. Contact us and we will confirm the current details with the distributor.\u003c\/p\u003e\n\u003cp\u003e\u003cstrong\u003eIs 90 mm big enough to be worth buying?\u003c\/strong\u003e For the Moon, the planets and bright clusters and nebulae, comfortably yes. For faint galaxies and dim nebulae, no, and you should step up to the 130 mm or 150 mm reflector if those are what you are after. Most beginners spend their first year on the objects a 90 mm handles well.\u003c\/p\u003e\n\u003cp\u003e\u003cstrong\u003eIs this a good telescope for a child?\u003c\/strong\u003e It is the best choice in this range for that. It is light enough for a child to help carry, there is no collimation to learn, and the eyepiece sits at a manageable height. Expect an adult to handle setup and finder alignment for the first few sessions.\u003c\/p\u003e\n\u003cp\u003e\u003cstrong\u003eHow does it compare with a good pair of binoculars?\u003c\/strong\u003e It shows considerably more. Binoculars are better for wide star fields and are more portable still, but they cannot deliver the magnification needed to show Saturn's rings or lunar crater detail, which is where this telescope earns its place.\u003c\/p\u003e\n\n\u003ch2\u003eBottom Line\u003c\/h2\u003e\n\u003cp\u003eThe Sidara Nano 90 is a small telescope that is honest about being one, and it does the things beginners actually spend their time on very well: the Moon, the planets, bright clusters, and getting outside quickly. Its slower focal ratio gives it cleaner images than its bigger achromatic siblings, which is a fair consolation for the aperture. If you are not sure whether to start here or step up to the 102 mm or 130 mm, contact our team in Bolton and we will help you match it to your skies and to who will be using it.\u003c\/p\u003e","brand":"Explore Scientific","offers":[{"title":"Default Title","offer_id":53958722093167,"sku":"ES-AR90700-MAZ-NANO","price":379.95,"currency_code":"CAD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0686\/0049\/6239\/files\/sidara_nano_90_v2.jpg?v=1785960942"}],"url":"https:\/\/ontariotelescope.com\/collections\/refractors-explore-scientific.oembed","provider":"Ontario Telescope and Accessories","version":"1.0","type":"link"}