{"title":"Explore Scientific AR Series","description":"\u003cp\u003eThe Explore Scientific AR Series line, listed by aperture. Part of \u003ca href=\"\/collections\/explore-scientific-telescopes\"\u003eExplore Scientific 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":1177.95,"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":1039.95,"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-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":415.95,"currency_code":"CAD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0686\/0049\/6239\/files\/ar_10211__08092.png?v=1766548214"}],"url":"https:\/\/ontariotelescope.com\/collections\/es-ar.oembed","provider":"Ontario Telescope and Accessories","version":"1.0","type":"link"}