{"title":"Takahashi TOE","description":"\u003cp\u003eEvery Takahashi TOE eyepiece we stock, listed by focal length.\u003c\/p\u003e","products":[{"product_id":"takahashi-toe-10mm-eyepiece","title":"Takahashi TOE 10mm Eyepiece","description":"\u003ch3\u003e\u003cstrong\u003eProduct Overview\u003c\/strong\u003e\u003c\/h3\u003e\u003cp\u003eThe TOE 10 mm sits at the long end of Takahashi's TOE planetary eyepiece line. It gives a 58° apparent field with 15 mm of eye relief, from six elements arranged in four groups — more glass than a classic orthoscopic, used to widen the field and push the eye point further back without giving up the contrast that makes an ortho worth using on planets.\u003c\/p\u003e\u003cp\u003eAt 10 mm it is the eyepiece you reach for when you want detail without pushing to the seeing limit: 35x on an FS-60CB, 76x on an FC-76D, 110x on a Mewlon 210.\u003c\/p\u003e\u003ch3\u003e\u003cstrong\u003eWho It's For\u003c\/strong\u003e\u003c\/h3\u003e\u003cp\u003eThis is a good match if you observe planets, the Moon and double stars and want an eyepiece whose contrast keeps up with a good apochromat. The 58° field is deliberately moderate — wide enough that the target does not drift out of view quickly on an undriven mount, narrow enough that the design can stay simple and well corrected.\u003c\/p\u003e\u003cp\u003eThe 15 mm eye relief is the practical difference from a traditional orthoscopic. Short-focal-length orthos put your eye almost against the lens; 15 mm gives room to observe comfortably, including over glasses in many cases.\u003c\/p\u003e\u003cp\u003eIt is a visual eyepiece. Imaging trains connect a camera directly and do not use one.\u003c\/p\u003e\u003ch3\u003e\u003cstrong\u003eKey Features \u0026amp; Design\u003c\/strong\u003e\u003c\/h3\u003e\u003cul\u003e\n\u003cli\u003e\n\u003cstrong\u003e10 mm focal length:\u003c\/strong\u003e medium-to-high power on most telescopes — the range where planetary detail appears without over-magnifying average seeing.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003e58° apparent field:\u003c\/strong\u003e wider than a classic orthoscopic, and enough that a planet stays in view for a usable interval on an undriven mount.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003e15 mm eye relief:\u003c\/strong\u003e a comfortable eye position rather than the pressed-in view short orthos demand.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eSix elements in four groups:\u003c\/strong\u003e the extra elements buy field width and eye relief while holding correction across the field.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eParfocal with the rest of the TOE range:\u003c\/strong\u003e swap focal lengths mid-session with only a touch of refocusing.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eBlackened element edges and multi-layer coatings:\u003c\/strong\u003e suppress the internal scatter that washes out low-contrast planetary detail.\u003c\/li\u003e\n\u003c\/ul\u003e\u003ch3\u003e\u003cstrong\u003eOptical Design\u003c\/strong\u003e\u003c\/h3\u003e\u003cp\u003ePlanetary observing is a contrast problem before it is a resolution problem. The features that matter — belt structure on Jupiter, the Cassini division, subtle shading on Mars — are low-contrast detail sitting on a bright disc, and any scattered light inside the eyepiece raises the background and buries them. That is why the classic four-element orthoscopic held on for decades: fewer air-glass surfaces, less scatter.\u003c\/p\u003e\u003cp\u003eThe TOE design accepts six elements in four groups and then attacks the scatter directly. Multi-layer coatings cut reflection at each surface, and the element edges are blackened so light striking them is absorbed rather than bounced back into the light path. The result keeps orthoscopic-class contrast while delivering a 58° field and 15 mm of eye relief — both well beyond what a four-element design produces at this focal length.\u003c\/p\u003e\u003cp\u003eParfocality across the range is a working convenience that matters more than it sounds: changing power on a planet mid-session without hunting for focus keeps you on the target while the seeing is steady.\u003c\/p\u003e\u003ch3\u003e\u003cstrong\u003eRecommended Uses\u003c\/strong\u003e\u003c\/h3\u003e\u003cul\u003e\n\u003cli\u003e\n\u003cstrong\u003ePlanetary detail\u003c\/strong\u003e — Jupiter's belts and festoons, Saturn's rings and division, Martian surface shading.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eLunar observing\u003c\/strong\u003e — crater walls, rilles and terminator detail at medium-high power.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eDouble star splitting\u003c\/strong\u003e where contrast and clean star images matter more than field width.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eBrighter open clusters and planetary nebulae\u003c\/strong\u003e at medium power.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eDaytime and terrestrial use\u003c\/strong\u003e with a suitable diagonal, where the long eye relief is comfortable.\u003c\/li\u003e\n\u003c\/ul\u003e\u003ch3\u003e\u003cstrong\u003eCompatibility and Accessory Notes\u003c\/strong\u003e\u003c\/h3\u003e\u003cul\u003e\n\u003cli\u003e\n\u003cstrong\u003eMagnification:\u003c\/strong\u003e divide your telescope's focal length by 10. An FS-60CB at 355 mm gives 35x; an FC-100DZ at 800 mm gives 80x; a Mewlon 210 at 2415 mm gives 242x.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eDiagonal:\u003c\/strong\u003e in a refractor you will normally use it behind a star diagonal. The Takahashi 1.25-inch prism diagonal is a direct pairing.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eParfocal range:\u003c\/strong\u003e parfocal with the other TOE eyepieces, so changing focal length needs only a touch of refocusing.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eFilters:\u003c\/strong\u003e standard eyepiece filters thread into the barrel where the barrel size matches.\u003c\/li\u003e\n\u003c\/ul\u003e\u003ch3\u003e\u003cstrong\u003eGood to Know Before You Order\u003c\/strong\u003e\u003c\/h3\u003e\u003cul\u003e\n\u003cli\u003e\n\u003cstrong\u003e58° is a moderate field, by design.\u003c\/strong\u003e If you want a 82° or 100° immersive view for sweeping deep-sky fields, this is not that eyepiece — it trades field width for contrast, which is the right trade on a planet and the wrong one on a large nebula.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eMagnification depends on your telescope.\u003c\/strong\u003e The same 10 mm gives 35x on a short 60 mm refractor and 242x on a Mewlon 210. Tell us your telescope and we will tell you where this lands in your eyepiece set.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eThis is a visual eyepiece.\u003c\/strong\u003e Camera trains connect directly to the telescope or its corrector.\u003c\/li\u003e\n\u003c\/ul\u003e\u003ch3\u003e\u003cstrong\u003eFrequently Asked Questions\u003c\/strong\u003e\u003c\/h3\u003e\u003cp\u003e\u003cstrong\u003eIs it difficult to set up?\u003c\/strong\u003e\u003c\/p\u003e\u003cp\u003eNo — it drops into a 1.25-inch diagonal or focuser and you focus. Nothing to assemble or adjust.\u003c\/p\u003e\u003cp\u003e\u003cstrong\u003eWhat magnification will I get?\u003c\/strong\u003e\u003c\/p\u003e\u003cp\u003eYour telescope's focal length divided by 10. Send us your telescope model and we will work out where it fits alongside the eyepieces you already own.\u003c\/p\u003e\u003cp\u003e\u003cstrong\u003eHow does it compare to a classic orthoscopic?\u003c\/strong\u003e\u003c\/p\u003e\u003cp\u003eA four-element ortho at 10 mm gives roughly a 42° to 45° field and short eye relief. The TOE gives 58° and 15 mm of eye relief from six elements, with coatings and blackened edges doing the contrast work the simpler design got from having fewer surfaces.\u003c\/p\u003e\u003cp\u003e\u003cstrong\u003eIs it good for deep-sky observing?\u003c\/strong\u003e\u003c\/p\u003e\u003cp\u003eIt works well on brighter open clusters and planetary nebulae. For large faint objects a wider field and longer focal length eyepiece suits better — this one is built around contrast at medium-high power.\u003c\/p\u003e\u003cp\u003e\u003cstrong\u003eCan I use it with glasses?\u003c\/strong\u003e\u003c\/p\u003e\u003cp\u003e15 mm of eye relief is workable for many glasses wearers, though it depends on your frames and how far they hold the lens from your eye.\u003c\/p\u003e\u003cp\u003e\u003cstrong\u003eWill it work with my Barlow or extender?\u003c\/strong\u003e\u003c\/p\u003e\u003cp\u003eYes — a 2x Barlow makes it behave as a 5 mm. Takahashi's Ortho Extender 2X and 4X are the matched options.\u003c\/p\u003e\u003cp\u003e\u003cstrong\u003eIs it parfocal with my other Takahashi eyepieces?\u003c\/strong\u003e\u003c\/p\u003e\u003cp\u003eIt is parfocal with the rest of the TOE range. Across other Takahashi families, expect to refocus.\u003c\/p\u003e\u003ch3\u003e\u003cstrong\u003eBottom Line\u003c\/strong\u003e\u003c\/h3\u003e\u003cp\u003eIn short: a 10 mm planetary eyepiece with a 58° field and 15 mm of eye relief, built from six elements with the coatings and blackened edges that keep low-contrast detail visible. It is the comfortable medium-power eyepiece in a planetary set.\u003c\/p\u003e","brand":"Takahashi","offers":[{"title":"Default Title","offer_id":54046970871919,"sku":"TAK-TKA00618","price":474.0,"currency_code":"CAD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0686\/0049\/6239\/files\/tka00618.jpg?v=1786907851"},{"product_id":"takahashi-toe-5-5mm-eyepiece","title":"Takahashi TOE 5.5mm Eyepiece","description":"\u003ch3\u003e\u003cstrong\u003eProduct Overview\u003c\/strong\u003e\u003c\/h3\u003e\u003cp\u003eThe TOE 5.5 mm is a high-power planetary eyepiece from Takahashi's TOE line, built for lunar, planetary and double-star observing. It gives a 58° apparent field with 15 mm of eye relief, from six elements in four groups — more glass than a classic orthoscopic, arranged to widen the field and push the eye point back without giving up the contrast an ortho is chosen for.\u003c\/p\u003e\u003cp\u003eAt 5.5 mm it is a high-power eyepiece: the number you reach for on a night of good seeing, when a telescope's aperture and the atmosphere both support pushing magnification.\u003c\/p\u003e\u003ch3\u003e\u003cstrong\u003eWho It's For\u003c\/strong\u003e\u003c\/h3\u003e\u003cp\u003eThis is a good match if you observe planets, the Moon and double stars and want high magnification without losing the contrast that separates orthoscopic-class eyepieces from wider, more complex designs. The 58° field is moderate by wide-field standards — wide enough that a planet does not drift out of view quickly on an undriven mount, narrow enough that the design can stay well corrected at high power.\u003c\/p\u003e\u003cp\u003eIt is a visual eyepiece. Imaging trains connect a camera directly and do not use one.\u003c\/p\u003e\u003ch3\u003e\u003cstrong\u003eKey Features \u0026amp; Design\u003c\/strong\u003e\u003c\/h3\u003e\u003cul\u003e\n\u003cli\u003e\n\u003cstrong\u003e5.5 mm focal length:\u003c\/strong\u003e high power on most telescopes — see Compatibility for real figures and the practical limits at this focal length.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003e58° apparent field:\u003c\/strong\u003e wider than a classic orthoscopic, with enough margin that a target stays in view for a usable interval on an undriven mount.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003e15 mm eye relief:\u003c\/strong\u003e a comfortable eye position rather than the pressed-in view short-focal-length orthos demand.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eSix elements in four groups:\u003c\/strong\u003e the extra elements buy field width and eye relief while holding correction across the field.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eParfocal within the TOE range:\u003c\/strong\u003e swap focal lengths mid-session with only a touch of refocusing.\u003c\/li\u003e\n\u003c\/ul\u003e\u003ch3\u003e\u003cstrong\u003eOptical Design\u003c\/strong\u003e\u003c\/h3\u003e\u003cp\u003ePlanetary observing is a contrast problem before it is a resolution problem. The detail that matters — belt structure on Jupiter, the Cassini division, subtle shading on Mars — is low-contrast detail sitting on a bright disc, and scattered light inside the eyepiece raises the background and buries it. That is why the classic four-element orthoscopic held on for decades: fewer air-glass surfaces means less scatter.\u003c\/p\u003e\u003cp\u003eThe TOE design uses six elements in four groups and controls scatter directly, with multi-layer coatings and blackened element edges rather than relying on a minimal element count. The result keeps orthoscopic-class contrast while delivering a 58° field and 15 mm of eye relief — both wider than a four-element design produces at this focal length. Parfocality across the TOE range is a working convenience: changing power on a planet mid-session without hunting for focus keeps you on the target while the seeing holds.\u003c\/p\u003e\u003ch3\u003e\u003cstrong\u003eRecommended Uses\u003c\/strong\u003e\u003c\/h3\u003e\u003cul\u003e\n\u003cli\u003e\n\u003cstrong\u003eHigh-power planetary detail\u003c\/strong\u003e on nights of good seeing — Jupiter's belts and festoons, Saturn's rings and division, Martian surface shading.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eLunar observing\u003c\/strong\u003e at close-up, crater-wall and rille detail.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eDouble star splitting\u003c\/strong\u003e at the close end, where high power and clean star images matter most.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eTesting a telescope's resolution\u003c\/strong\u003e on a steady night, since 5.5 mm pushes most apertures toward their practical ceiling.\u003c\/li\u003e\n\u003c\/ul\u003e\u003ch3\u003e\u003cstrong\u003eCompatibility and Accessory Notes\u003c\/strong\u003e\u003c\/h3\u003e\u003cul\u003e\n\u003cli\u003e\n\u003cstrong\u003eMagnification:\u003c\/strong\u003e divide your telescope's focal length by 5.5. An FS-60CB at 355 mm gives about 65x; an FC-100DZ at 800 mm gives about 145x; a Mewlon 210 at 2415 mm gives about 439x — above the roughly 420x practical ceiling usually quoted for a 210 mm aperture, so that combination is a seeing-limited, best-nights eyepiece rather than an everyday one.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eDiagonal:\u003c\/strong\u003e in a refractor you will normally use it behind a star diagonal. The Takahashi 1.25-inch prism diagonal is a direct pairing.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eParfocal range:\u003c\/strong\u003e parfocal with the other TOE eyepieces, so changing focal length needs only a touch of refocusing.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eBack focus:\u003c\/strong\u003e for adapter and spacing questions across your visual train, see the \u003ca href=\"\/pages\/takahashi-back-focus-guide\"\u003eTakahashi Back Focus Guide\u003c\/a\u003e.\u003c\/li\u003e\n\u003c\/ul\u003e\u003ch3\u003e\u003cstrong\u003eGood to Know Before You Order\u003c\/strong\u003e\u003c\/h3\u003e\u003cul\u003e\n\u003cli\u003e\n\u003cstrong\u003e5.5 mm is a high-power eyepiece, and results depend on the sky.\u003c\/strong\u003e On a smaller aperture like an FS-60CB it stays well within useful range; on a larger telescope like a Mewlon 210 it can exceed the aperture's practical magnification ceiling, and results will depend on seeing more than on the eyepiece.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eThis is a visual eyepiece.\u003c\/strong\u003e Camera trains connect directly to the telescope or its corrector.\u003c\/li\u003e\n\u003c\/ul\u003e\u003ch3\u003e\u003cstrong\u003eFrequently Asked Questions\u003c\/strong\u003e\u003c\/h3\u003e\u003cp\u003e\u003cstrong\u003eIs it difficult to set up?\u003c\/strong\u003e\u003c\/p\u003e\u003cp\u003eNo — it drops into a 1.25-inch diagonal or focuser and you focus. Nothing to assemble or adjust.\u003c\/p\u003e\u003cp\u003e\u003cstrong\u003eWhat magnification will I get?\u003c\/strong\u003e\u003c\/p\u003e\u003cp\u003eYour telescope's focal length divided by 5.5. Send us your telescope model and we will work out where it fits alongside the eyepieces you already own — and whether it is within your aperture's useful range.\u003c\/p\u003e\u003cp\u003e\u003cstrong\u003eHow does it compare to a classic orthoscopic?\u003c\/strong\u003e\u003c\/p\u003e\u003cp\u003eA four-element ortho at 5.5 mm gives roughly a 42° to 45° field and short eye relief. The TOE gives 58° and 15 mm of eye relief from six elements, with coatings and blackened edges doing the contrast work the simpler design got from having fewer surfaces.\u003c\/p\u003e\u003cp\u003e\u003cstrong\u003eIs it good for deep-sky observing?\u003c\/strong\u003e\u003c\/p\u003e\u003cp\u003eIt is built for high-power planetary and lunar detail rather than deep-sky work — for clusters and nebulae, a longer-focal-length, wider-field eyepiece suits better.\u003c\/p\u003e\u003cp\u003e\u003cstrong\u003eCan I use it with glasses?\u003c\/strong\u003e\u003c\/p\u003e\u003cp\u003e15 mm of eye relief is workable for many glasses wearers, though it depends on your frames and how far they hold the lens from your eye.\u003c\/p\u003e\u003cp\u003e\u003cstrong\u003eIs it parfocal with my other Takahashi eyepieces?\u003c\/strong\u003e\u003c\/p\u003e\u003cp\u003eIt is parfocal with the rest of the TOE range. Across other Takahashi families, expect to refocus.\u003c\/p\u003e\u003cp\u003e\u003cstrong\u003eWill it work on a small telescope, or is it too much power?\u003c\/strong\u003e\u003c\/p\u003e\u003cp\u003eOn an FS-60CB it gives about 65x, which is a normal high-power step, not an extreme one. It is on larger apertures, closer to their magnification ceiling, that seeing becomes the limiting factor.\u003c\/p\u003e\u003ch3\u003e\u003cstrong\u003eBottom Line\u003c\/strong\u003e\u003c\/h3\u003e\u003cp\u003eIn short: a 5.5 mm planetary eyepiece with a 58° field and 15 mm of eye relief, built from six elements with the coatings and blackened edges that keep low-contrast detail visible at high power. It is the high-power step in a planetary set, most rewarding on nights when the seeing can support it.\u003c\/p\u003e","brand":"Takahashi","offers":[{"title":"Default Title","offer_id":54047076909167,"sku":"TAK-TKA00616","price":474.0,"currency_code":"CAD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0686\/0049\/6239\/files\/tka00616.jpg?v=1786912894"},{"product_id":"takahashi-toe-7-5mm-eyepiece","title":"Takahashi TOE 7.5mm Eyepiece","description":"\u003ch3\u003e\u003cstrong\u003eProduct Overview\u003c\/strong\u003e\u003c\/h3\u003e\u003cp\u003eThe TOE 7.5 mm is a planetary eyepiece from Takahashi's TOE line, built for lunar, planetary and double-star observing. It gives a 58° apparent field with 15 mm of eye relief — wider and with more eye relief than a classic orthoscopic offers at this focal length. The TOE line uses a multi-element design built to hold orthoscopic-class contrast across a wider field and a longer eye point than a classic ortho manages.\u003c\/p\u003e\u003cp\u003eAt 7.5 mm it sits between the TOE 5.5 mm and TOE 10 mm — high power with a bit more eye relief and a slightly wider true field than the shortest focal length in the range.\u003c\/p\u003e\u003ch3\u003e\u003cstrong\u003eWho It's For\u003c\/strong\u003e\u003c\/h3\u003e\u003cp\u003eThis is a good match if you observe planets, the Moon and double stars and want high-to-medium magnification without losing contrast. The 58° field is moderate by wide-field standards — wide enough that a planet does not drift out of view quickly on an undriven mount, narrow enough that the design can stay well corrected at high power.\u003c\/p\u003e\u003cp\u003eIt is a visual eyepiece. Imaging trains connect a camera directly and do not use one.\u003c\/p\u003e\u003ch3\u003e\u003cstrong\u003eKey Features \u0026amp; Design\u003c\/strong\u003e\u003c\/h3\u003e\u003cul\u003e\n\u003cli\u003e\n\u003cstrong\u003e7.5 mm focal length:\u003c\/strong\u003e high-to-medium power on most telescopes — see Compatibility for real figures.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003e58° apparent field:\u003c\/strong\u003e wider than a classic orthoscopic, with enough margin that a target stays in view for a usable interval on an undriven mount.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003e15 mm eye relief:\u003c\/strong\u003e a comfortable eye position rather than the pressed-in view short-focal-length orthos demand.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eParfocal within the TOE range:\u003c\/strong\u003e swap focal lengths mid-session with only a touch of refocusing.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eMulti-element TOE design:\u003c\/strong\u003e built for orthoscopic-class contrast at a wider field than a classic ortho.\u003c\/li\u003e\n\u003c\/ul\u003e\u003ch3\u003e\u003cstrong\u003eOptical Design\u003c\/strong\u003e\u003c\/h3\u003e\u003cp\u003ePlanetary observing is a contrast problem before it is a resolution problem. The detail that matters — belt structure on Jupiter, the Cassini division, subtle shading on Mars — is low-contrast detail sitting on a bright disc, and scattered light inside the eyepiece raises the background and buries it. That is why the classic four-element orthoscopic held on for decades: fewer air-glass surfaces means less scatter.\u003c\/p\u003e\u003cp\u003eAcross the TOE line, Takahashi controls scatter with multi-layer coatings and blackened element edges rather than relying on a minimal element count, which is how the series holds orthoscopic-class contrast at a 58° field and 15 mm of eye relief — both wider than a classic four-element ortho manages at comparable focal lengths.\u003c\/p\u003e\u003ch3\u003e\u003cstrong\u003eRecommended Uses\u003c\/strong\u003e\u003c\/h3\u003e\u003cul\u003e\n\u003cli\u003e\n\u003cstrong\u003ePlanetary detail\u003c\/strong\u003e — Jupiter's belts and festoons, Saturn's rings and division, Martian surface shading.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eLunar observing\u003c\/strong\u003e — crater walls, rilles and terminator detail at high-to-medium power.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eDouble star splitting\u003c\/strong\u003e where contrast and clean star images matter more than field width.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eBrighter open clusters and planetary nebulae\u003c\/strong\u003e at higher power.\u003c\/li\u003e\n\u003c\/ul\u003e\u003ch3\u003e\u003cstrong\u003eCompatibility and Accessory Notes\u003c\/strong\u003e\u003c\/h3\u003e\u003cul\u003e\n\u003cli\u003e\n\u003cstrong\u003eMagnification:\u003c\/strong\u003e divide your telescope's focal length by 7.5. An FS-60CB at 355 mm gives about 47x; an FC-100DZ at 800 mm gives about 107x; a Mewlon 210 at 2415 mm gives about 322x.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eDiagonal:\u003c\/strong\u003e in a refractor you will normally use it behind a star diagonal. The Takahashi 1.25-inch prism diagonal is a direct pairing.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eParfocal range:\u003c\/strong\u003e parfocal with the other TOE eyepieces, so changing focal length needs only a touch of refocusing.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eBack focus:\u003c\/strong\u003e for adapter and spacing questions across your visual train, see the \u003ca href=\"\/pages\/takahashi-back-focus-guide\"\u003eTakahashi Back Focus Guide\u003c\/a\u003e.\u003c\/li\u003e\n\u003c\/ul\u003e\u003ch3\u003e\u003cstrong\u003eGood to Know Before You Order\u003c\/strong\u003e\u003c\/h3\u003e\u003cul\u003e\n\u003cli\u003e\n\u003cstrong\u003eThis is a visual eyepiece.\u003c\/strong\u003e Camera trains connect directly to the telescope or its corrector.\u003c\/li\u003e\n\u003c\/ul\u003e\u003ch3\u003e\u003cstrong\u003eFrequently Asked Questions\u003c\/strong\u003e\u003c\/h3\u003e\u003cp\u003e\u003cstrong\u003eIs it difficult to set up?\u003c\/strong\u003e\u003c\/p\u003e\u003cp\u003eNo — it drops into a 1.25-inch diagonal or focuser and you focus. Nothing to assemble or adjust.\u003c\/p\u003e\u003cp\u003e\u003cstrong\u003eWhat magnification will I get?\u003c\/strong\u003e\u003c\/p\u003e\u003cp\u003eYour telescope's focal length divided by 7.5. Send us your telescope model and we will work out where it fits alongside the eyepieces you already own.\u003c\/p\u003e\u003cp\u003e\u003cstrong\u003eHow does it compare to a classic orthoscopic?\u003c\/strong\u003e\u003c\/p\u003e\u003cp\u003eA four-element ortho at 7.5 mm gives roughly a 42° to 45° field and short eye relief. The TOE gives 58° and 15 mm of eye relief, with coatings and blackened edges doing the contrast work a simpler design got from having fewer surfaces.\u003c\/p\u003e\u003cp\u003e\u003cstrong\u003eIs it good for deep-sky observing?\u003c\/strong\u003e\u003c\/p\u003e\u003cp\u003eIt works well on brighter open clusters and planetary nebulae. For large faint objects a longer-focal-length, wider-field eyepiece suits better.\u003c\/p\u003e\u003cp\u003e\u003cstrong\u003eCan I use it with glasses?\u003c\/strong\u003e\u003c\/p\u003e\u003cp\u003e15 mm of eye relief is workable for many glasses wearers, though it depends on your frames and how far they hold the lens from your eye.\u003c\/p\u003e\u003cp\u003e\u003cstrong\u003eIs it parfocal with my other Takahashi eyepieces?\u003c\/strong\u003e\u003c\/p\u003e\u003cp\u003eIt is parfocal with the rest of the TOE range. Across other Takahashi families, expect to refocus.\u003c\/p\u003e\u003cp\u003e\u003cstrong\u003eHow does it compare to the TOE 5.5mm and TOE 10mm?\u003c\/strong\u003e\u003c\/p\u003e\u003cp\u003eIt sits between them in power — higher magnification than the 10 mm, more eye relief and a slightly wider true field than the 5.5 mm.\u003c\/p\u003e\u003ch3\u003e\u003cstrong\u003eBottom Line\u003c\/strong\u003e\u003c\/h3\u003e\u003cp\u003eIn short: a 7.5 mm planetary eyepiece with a 58° field and 15 mm of eye relief, built for orthoscopic-class contrast at high-to-medium power. It sits between the shorter and longer focal lengths in the TOE range.\u003c\/p\u003e","brand":"Takahashi","offers":[{"title":"Default Title","offer_id":54047078678639,"sku":"TAK-TKA00617","price":474.0,"currency_code":"CAD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0686\/0049\/6239\/files\/tka00617-1.jpg?v=1786912932"},{"product_id":"takahashi-toe-2-5mm-eyepiece-1-25","title":"Takahashi TOE 2.5mm Eyepiece - 1.25\"","description":"\u003ch3\u003e\u003cstrong\u003eProduct Overview\u003c\/strong\u003e\u003c\/h3\u003e\u003cp\u003eThe TOE 2.5 mm is the shortest eyepiece in Takahashi's TOE planetary line — the one that asks the most of the telescope, the mount and the night. It gives a 52° apparent field with 10 mm of eye relief from six elements in four groups, in a 31.7 mm (1.25-inch) barrel, and weighs 145 g.\u003c\/p\u003e\u003cp\u003eTakahashi describes the TOE range as delivering performance close to the diffraction limit over the entire field of view when paired with a premium telescope. At 2.5 mm that lands at the top of almost any power range: 142x on an FS-60CB, 228x on an FC-76DCU, 320x on an FC-100DZ.\u003c\/p\u003e\u003ch3\u003e\u003cstrong\u003eWho It's For\u003c\/strong\u003e\u003c\/h3\u003e\u003cp\u003eThis is a good match if you observe planets, the Moon and close double stars, and want the high end of your eyepiece set covered by a design built around contrast rather than field width. It earns its keep on the nights when the seeing settles and a shorter focal length telescope can be pushed further than usual.\u003c\/p\u003e\u003cp\u003eThe 52° field is moderate by design. At this magnification the trade is deliberate — a simpler, better-corrected field rather than an immersive one, because what limits planetary detail is scatter and contrast, not how much sky is in view.\u003c\/p\u003e\u003cp\u003eIt is a visual eyepiece. Imaging trains connect a camera directly to the telescope or its corrector and do not use one.\u003c\/p\u003e\u003ch3\u003e\u003cstrong\u003eKey Features \u0026amp; Design\u003c\/strong\u003e\u003c\/h3\u003e\u003cul\u003e\n\u003cli\u003e\n\u003cstrong\u003e2.5 mm focal length:\u003c\/strong\u003e the shortest in the TOE line, for the top of your power range on short and medium focal length telescopes.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003e52° apparent field:\u003c\/strong\u003e moderate by intent, keeping the design simple and well corrected across the field.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003e10 mm eye relief:\u003c\/strong\u003e four times the focal length, which is generous at this end of the range and makes a long session at high power comfortable.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eSix elements in four groups:\u003c\/strong\u003e more glass than a classic orthoscopic, used to hold the field and the eye point without giving up correction.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003e31.7 mm (1.25-inch) barrel:\u003c\/strong\u003e drops into any 1.25-inch diagonal or focuser.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003e145 g:\u003c\/strong\u003e light enough that it changes nothing about focuser balance.\u003c\/li\u003e\n\u003c\/ul\u003e\u003ch3\u003e\u003cstrong\u003eOptical Design\u003c\/strong\u003e\u003c\/h3\u003e\u003cp\u003ePlanetary observing is a contrast problem before it is a resolution problem. Belt structure on Jupiter, the Cassini division, shading on Mars — these are low-contrast features sitting on a bright disc, and light scattered inside the eyepiece raises the background and buries them. That is why the four-element orthoscopic held its place for so long: fewer air-glass surfaces, less scatter.\u003c\/p\u003e\u003cp\u003eThe TOE design takes six elements in four groups and spends the extra surfaces on field correction and eye relief. At 2.5 mm those are the two things a simple design struggles with most — a short orthoscopic puts the eye point almost on the glass, and its field edge softens. Ten millimetres of eye relief and a corrected 52° field are what the additional elements buy back.\u003c\/p\u003e\u003cp\u003eTakahashi lists the 2.5 mm as not parfocal, so expect to refocus when you swap it for another eyepiece rather than picking up where you left off.\u003c\/p\u003e\u003ch3\u003e\u003cstrong\u003eRecommended Uses\u003c\/strong\u003e\u003c\/h3\u003e\u003cul\u003e\n\u003cli\u003e\n\u003cstrong\u003ePlanetary detail\u003c\/strong\u003e — Jupiter's belts and festoons, Saturn's rings and division, surface shading on Mars, on nights when the seeing supports the magnification.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eLunar observing\u003c\/strong\u003e — crater floors, rilles and terminator detail at high power.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eClose double stars\u003c\/strong\u003e where separation, not field width, is the whole job.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eTesting and collimation checks\u003c\/strong\u003e where a high-power star image is what you are looking at.\u003c\/li\u003e\n\u003c\/ul\u003e\u003ch3\u003e\u003cstrong\u003eCompatibility and Accessory Notes\u003c\/strong\u003e\u003c\/h3\u003e\u003cul\u003e\n\u003cli\u003e\n\u003cstrong\u003eMagnification:\u003c\/strong\u003e divide your telescope's focal length by 2.5. An FS-60CB at 355 mm gives 142x; an FC-76DCU at 570 mm gives 228x; an FC-100DZ at 800 mm gives 320x; a TOA-130 at 1000 mm gives 400x.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eBarrel size:\u003c\/strong\u003e 31.7 mm (1.25-inch) — fits any 1.25-inch focuser or diagonal. The Takahashi 1.25-inch multicoated prism star diagonal is a direct pairing.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eFilters:\u003c\/strong\u003e standard 1.25-inch filters thread into the barrel.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eParfocality:\u003c\/strong\u003e Takahashi lists this eyepiece as not parfocal, so a focal length change means a focus change.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eBarlows and extenders:\u003c\/strong\u003e at 2.5 mm you are already at the short end, so this is usually the eyepiece a Barlow is not used with. If you are unsure where it sits alongside what you already own, send us your telescope and eyepiece set and we will map it out with you.\u003c\/li\u003e\n\u003c\/ul\u003e\u003ch3\u003e\u003cstrong\u003eGood to Know Before You Order\u003c\/strong\u003e\u003c\/h3\u003e\u003cul\u003e\n\u003cli\u003e\n\u003cstrong\u003eMagnification depends entirely on your telescope.\u003c\/strong\u003e The same 2.5 mm gives 142x on a 355 mm FS-60CB and 400x on a 1000 mm TOA-130. Tell us what you are observing with and we will tell you where this lands in your set.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eThe sky sets the ceiling, not the eyepiece.\u003c\/strong\u003e Very high power rewards steady seeing and a well-cooled telescope. On an average night a longer TOE will show more; on a good one this is the eyepiece that pays off.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eIt is not parfocal.\u003c\/strong\u003e Refocus after swapping — Takahashi publishes this for the 2.5 mm specifically.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003e52° is a moderate field.\u003c\/strong\u003e At this power a target crosses it quickly on an undriven mount, so a tracking mount makes the eyepiece much easier to live with.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eThis is a visual eyepiece.\u003c\/strong\u003e Camera trains connect directly to the telescope or its corrector.\u003c\/li\u003e\n\u003c\/ul\u003e\u003ch3\u003e\u003cstrong\u003eFrequently Asked Questions\u003c\/strong\u003e\u003c\/h3\u003e\u003cp\u003e\u003cstrong\u003eIs it difficult to set up?\u003c\/strong\u003e\u003c\/p\u003e\u003cp\u003eNo — it drops into a 1.25-inch diagonal or focuser and you focus. There is nothing to assemble, thread or space.\u003c\/p\u003e\u003cp\u003e\u003cstrong\u003eWhat magnification will I get?\u003c\/strong\u003e\u003c\/p\u003e\u003cp\u003eYour telescope's focal length divided by 2.5. Send us your telescope model and we will work out where it fits alongside the eyepieces you already own.\u003c\/p\u003e\u003cp\u003e\u003cstrong\u003eIs 2.5 mm too short for my telescope?\u003c\/strong\u003e\u003c\/p\u003e\u003cp\u003eIt depends on focal length and on your sky. On short refractors it produces a sensible high power; on long focal length telescopes it goes well past what most nights support. That is a conversation worth having before you order — send us your setup.\u003c\/p\u003e\u003cp\u003e\u003cstrong\u003eHow does it compare to a classic orthoscopic at this focal length?\u003c\/strong\u003e\u003c\/p\u003e\u003cp\u003eA four-element ortho at 2.5 mm gives a narrower field and an eye point almost against the glass. The TOE uses six elements in four groups to hold a corrected 52° field with 10 mm of eye relief.\u003c\/p\u003e\u003cp\u003e\u003cstrong\u003eIs it parfocal with my other TOE eyepieces?\u003c\/strong\u003e\u003c\/p\u003e\u003cp\u003eTakahashi lists the 2.5 mm as not parfocal, so plan on refocusing when you change eyepieces.\u003c\/p\u003e\u003cp\u003e\u003cstrong\u003eCan I use it with glasses?\u003c\/strong\u003e\u003c\/p\u003e\u003cp\u003eTen millimetres of eye relief is workable for some frames and tight for others. If you observe with glasses on, a longer TOE will be more comfortable.\u003c\/p\u003e\u003cp\u003e\u003cstrong\u003eCan I use it for astrophotography?\u003c\/strong\u003e\u003c\/p\u003e\u003cp\u003eNo — it is a visual eyepiece. Imaging trains connect the camera to the telescope or its corrector directly.\u003c\/p\u003e\u003ch3\u003e\u003cstrong\u003eBottom Line\u003c\/strong\u003e\u003c\/h3\u003e\u003cp\u003eIn short: a 2.5 mm planetary eyepiece with a 52° field, 10 mm of eye relief and six elements in four groups, in a 1.25-inch barrel. It is the top-of-the-range power in a planetary set, and it does its best work on a steady night behind a well-cooled telescope.\u003c\/p\u003e","brand":"Takahashi","offers":[{"title":"Default Title","offer_id":54070495248495,"sku":"TAK-TKA00613","price":474.0,"currency_code":"CAD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0686\/0049\/6239\/files\/tka00613_2_5.jpg?v=1787169096"},{"product_id":"takahashi-toe-3-3mm-eyepiece-1-25","title":"Takahashi TOE 3.3mm Eyepiece - 1.25\"","description":"\u003ch3\u003e\u003cstrong\u003eProduct Overview\u003c\/strong\u003e\u003c\/h3\u003e\u003cp\u003eThe TOE 3.3 mm is the shortest focal length in Takahashi's TOE range — a 1.25″ eyepiece built for high-magnification visual observing. Its six-element optical design minimises spherical and chromatic aberration, and the 52° apparent field matches that of Takahashi's LE series, with 10 mm of eye relief.\u003c\/p\u003e\u003cp\u003eAt 3.3 mm, this is a planetary and double-star eyepiece. On a 1000 mm telescope it delivers roughly 300x; on a 2500 mm Mewlon, above 750x — magnifications that reward good optics and steady seeing.\u003c\/p\u003e\u003ch3\u003e\u003cstrong\u003eWho It's For\u003c\/strong\u003e\u003c\/h3\u003e\u003cp\u003eThis is a good match if you observe planets, the Moon, or close double stars and want the shortest focal length in the TOE line on a premium telescope.\u003c\/p\u003e\u003ch3\u003e\u003cstrong\u003eKey Features \u0026amp; Design\u003c\/strong\u003e\u003c\/h3\u003e\u003cul\u003e\n\u003cli\u003e\n\u003cstrong\u003e3.3 mm focal length:\u003c\/strong\u003e the highest magnification in the TOE range.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003e52° apparent field:\u003c\/strong\u003e matched to Takahashi's LE series.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003e10 mm eye relief:\u003c\/strong\u003e consistent across the TOE line.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eSix-element design:\u003c\/strong\u003e minimises spherical and chromatic aberration.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003e1.25″ barrel:\u003c\/strong\u003e fits any standard 1.25″ focuser or diagonal.\u003c\/li\u003e\n\u003c\/ul\u003e\u003ch3\u003e\u003cstrong\u003eOptical \/ Mechanical Design\u003c\/strong\u003e\u003c\/h3\u003e\u003cp\u003eA short-focal-length eyepiece is the hardest kind to build well. Aberrations that stay invisible at 25 mm become obvious at 3.3 mm, and simple designs tend to give up eye relief as focal length falls — which is why cheap high-power eyepieces are so uncomfortable to use. The TOE answers both with six elements: enough degrees of freedom to control spherical and chromatic error while holding eye relief at 10 mm even at this focal length. Takahashi's stated aim for the range is performance close to the diffraction limit across the whole field when paired with a premium telescope.\u003c\/p\u003e\u003ch3\u003e\u003cstrong\u003eRecommended Uses\u003c\/strong\u003e\u003c\/h3\u003e\u003cp\u003eHigh-magnification visual observing: planetary detail, lunar features at the terminator, and splitting close double stars.\u003c\/p\u003e\u003ch3\u003e\u003cstrong\u003eCompatibility and Accessory Notes\u003c\/strong\u003e\u003c\/h3\u003e\u003cp\u003eThe 1.25″ barrel fits any standard 1.25″ focuser, diagonal, or 2″-to-1.25″ adapter. Takahashi publishes this eyepiece as \u003cstrong\u003enot parfocal\u003c\/strong\u003e, so refocusing is needed when swapping to another eyepiece. The TOE line also includes 4 mm, 5.5 mm, 7.5 mm and 10 mm focal lengths, which we stock — if you are building a set and want to space the magnifications sensibly on your telescope, tell us the focal length and we will suggest a combination.\u003c\/p\u003e\u003ch3\u003e\u003cstrong\u003eGood to Know Before You Order\u003c\/strong\u003e\u003c\/h3\u003e\u003cp\u003e\u003cstrong\u003eA visual eyepiece:\u003c\/strong\u003e the TOE is designed for the eye rather than a sensor, and has no application in a prime-focus imaging train.\u003c\/p\u003e\u003cp\u003e\u003cstrong\u003eNot parfocal:\u003c\/strong\u003e swapping between TOE focal lengths needs a touch of refocusing.\u003c\/p\u003e\u003cp\u003e\u003cstrong\u003eMagnification depends on your telescope:\u003c\/strong\u003e divide your focal length by 3.3. On longer instruments this eyepiece reaches magnifications that only steady seeing will support — which is exactly what it is built for, and worth pairing with a longer TOE for nights when the air is not cooperating.\u003c\/p\u003e\u003ch3\u003e\u003cstrong\u003eFrequently Asked Questions\u003c\/strong\u003e\u003c\/h3\u003e\u003cp\u003e\u003cstrong\u003eIs it difficult to set up?\u003c\/strong\u003e\u003c\/p\u003e\u003cp\u003eNo — it drops into a 1.25″ focuser or diagonal like any eyepiece. It does need refocusing when you swap eyepieces, since the TOEs are not parfocal.\u003c\/p\u003e\u003cp\u003e\u003cstrong\u003eWhat magnification will I get?\u003c\/strong\u003e\u003c\/p\u003e\u003cp\u003eYour telescope's focal length divided by 3.3. A 1000 mm telescope gives about 300x.\u003c\/p\u003e\u003cp\u003e\u003cstrong\u003eWhat is it best used for?\u003c\/strong\u003e\u003c\/p\u003e\u003cp\u003ePlanets, the Moon, and close double stars — targets that reward high magnification.\u003c\/p\u003e\u003cp\u003e\u003cstrong\u003eIs the eye relief comfortable?\u003c\/strong\u003e\u003c\/p\u003e\u003cp\u003e10 mm, which is generous for a 3.3 mm eyepiece; short focal lengths in simpler designs typically offer far less.\u003c\/p\u003e\u003cp\u003e\u003cstrong\u003eCan I use it for astrophotography?\u003c\/strong\u003e\u003c\/p\u003e\u003cp\u003eIt is a visual eyepiece and has no application in a prime-focus imaging train.\u003c\/p\u003e\u003ch3\u003e\u003cstrong\u003eBottom Line\u003c\/strong\u003e\u003c\/h3\u003e\u003cp\u003eTakahashi's shortest TOE — a six-element 3.3 mm eyepiece with a 52° field and 10 mm of eye relief, made for the nights when the seeing lets you push the magnification.\u003c\/p\u003e","brand":"Takahashi","offers":[{"title":"Default Title","offer_id":54086046449775,"sku":"TAK-TKA00614","price":474.0,"currency_code":"CAD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0686\/0049\/6239\/files\/tka00614_2_5.jpg?v=1787329004"},{"product_id":"takahashi-toe-4mm-eyepiece","title":"Takahashi TOE 4mm Eyepiece","description":"\u003ch3\u003e\u003cstrong\u003eProduct Overview\u003c\/strong\u003e\u003c\/h3\u003e\u003cp\u003eThe TOE 4 mm is built for high-magnification visual observing. Paired with a premium telescope, Takahashi designed the TOE range to deliver performance close to the diffraction limit across the entire field of view. The apparent field is 52° — similar to Takahashi's LE series — with 10 mm of eye relief.\u003c\/p\u003e\u003cp\u003eThe optical design uses six elements in four groups, chosen to minimise spherical aberration, chromatic aberration, field curvature and astigmatism together rather than trading one against another.\u003c\/p\u003e\u003ch3\u003e\u003cstrong\u003eWho It's For\u003c\/strong\u003e\u003c\/h3\u003e\u003cp\u003eThis is a good match if you observe planets, the Moon or double stars and want a short-focal-length eyepiece that holds up under high power.\u003c\/p\u003e\u003ch3\u003e\u003cstrong\u003eKey Features \u0026amp; Design\u003c\/strong\u003e\u003c\/h3\u003e\u003cul\u003e\n\u003cli\u003e\n\u003cstrong\u003e4 mm focal length:\u003c\/strong\u003e high magnification on any telescope.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003e52° apparent field:\u003c\/strong\u003e matched to Takahashi's LE series.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003e10 mm eye relief:\u003c\/strong\u003e generous for this focal length.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003e6 elements in 4 groups:\u003c\/strong\u003e controls spherical and chromatic aberration, field curvature and astigmatism.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eClose to the diffraction limit across the field:\u003c\/strong\u003e Takahashi's stated design target for the range on a premium telescope.\u003c\/li\u003e\n\u003c\/ul\u003e\u003ch3\u003e\u003cstrong\u003eOptical \/ Mechanical Design\u003c\/strong\u003e\u003c\/h3\u003e\u003cp\u003eSix elements in four groups is a substantial design for a 4 mm eyepiece, and the element count is what buys the correction. Four separate aberrations are being controlled at once here — spherical and chromatic error, which soften the image everywhere, and field curvature and astigmatism, which specifically degrade the outer field. Simpler high-power designs typically correct the centre and let the edges go, or hold the field and give up eye relief. Retaining 10 mm of eye relief at 4 mm focal length is the practical benefit: the eye sits at a workable distance rather than pressed against the lens, which matters over a long planetary session.\u003c\/p\u003e\u003ch3\u003e\u003cstrong\u003eRecommended Uses\u003c\/strong\u003e\u003c\/h3\u003e\u003cp\u003eHigh-magnification visual observing: planetary detail, lunar features, and splitting double stars.\u003c\/p\u003e\u003ch3\u003e\u003cstrong\u003eCompatibility and Accessory Notes\u003c\/strong\u003e\u003c\/h3\u003e\u003cp\u003eFits standard focusers and diagonals. Takahashi publishes this eyepiece as \u003cstrong\u003enot parfocal\u003c\/strong\u003e, so a touch of refocusing is needed when swapping eyepieces. The TOE line also includes 3.3 mm, 5.5 mm, 7.5 mm and 10 mm focal lengths, all of which we stock — tell us your telescope's focal length and we will suggest a set that spaces the magnifications sensibly.\u003c\/p\u003e\u003ch3\u003e\u003cstrong\u003eGood to Know Before You Order\u003c\/strong\u003e\u003c\/h3\u003e\u003cp\u003e\u003cstrong\u003eA visual eyepiece:\u003c\/strong\u003e designed for the eye rather than a sensor, with no application in a prime-focus imaging train.\u003c\/p\u003e\u003cp\u003e\u003cstrong\u003eNot parfocal:\u003c\/strong\u003e refocusing is needed between TOE focal lengths.\u003c\/p\u003e\u003cp\u003e\u003cstrong\u003eMagnification depends on your telescope:\u003c\/strong\u003e divide your focal length by 4. On a long instrument that is a lot of magnification, so it pairs well with a longer TOE for less steady nights.\u003c\/p\u003e\u003ch3\u003e\u003cstrong\u003eFrequently Asked Questions\u003c\/strong\u003e\u003c\/h3\u003e\u003cp\u003e\u003cstrong\u003eIs it difficult to set up?\u003c\/strong\u003e\u003c\/p\u003e\u003cp\u003eNo — it drops into the focuser or diagonal like any eyepiece, with a touch of refocusing when you swap.\u003c\/p\u003e\u003cp\u003e\u003cstrong\u003eWhat magnification will I get?\u003c\/strong\u003e\u003c\/p\u003e\u003cp\u003eYour telescope's focal length divided by 4. A 1000 mm telescope gives 250x.\u003c\/p\u003e\u003cp\u003e\u003cstrong\u003eWhat is it best used for?\u003c\/strong\u003e\u003c\/p\u003e\u003cp\u003ePlanets, the Moon, and double stars.\u003c\/p\u003e\u003cp\u003e\u003cstrong\u003eHow does it compare with the 3.3mm?\u003c\/strong\u003e\u003c\/p\u003e\u003cp\u003eSame 52° field and 10 mm eye relief; the 3.3 mm gives more magnification and asks more of the seeing.\u003c\/p\u003e\u003cp\u003e\u003cstrong\u003eCan I use it for astrophotography?\u003c\/strong\u003e\u003c\/p\u003e\u003cp\u003eIt is a visual eyepiece with no application in a prime-focus imaging train.\u003c\/p\u003e\u003ch3\u003e\u003cstrong\u003eBottom Line\u003c\/strong\u003e\u003c\/h3\u003e\u003cp\u003eA six-element 4 mm eyepiece with a 52° field and 10 mm of eye relief — Takahashi's high-power option for planetary and lunar work.\u003c\/p\u003e","brand":"Takahashi","offers":[{"title":"Default Title","offer_id":54086046908527,"sku":"TAK-TKA00615","price":474.0,"currency_code":"CAD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0686\/0049\/6239\/files\/tka00615_2_5.jpg?v=1787329029"}],"url":"https:\/\/ontariotelescope.com\/collections\/takahashi-toe.oembed","provider":"Ontario Telescope and Accessories","version":"1.0","type":"link"}