{"product_id":"takahashi-foa-60q-60mm-f-15-ortho-apochromatic-refractor-ota","title":"Takahashi FOA-60Q 60mm f\/15 Ortho Apochromatic Refractor OTA","description":"\u003ch3\u003e\u003cstrong\u003eProduct Overview\u003c\/strong\u003e\u003c\/h3\u003e\u003cp\u003eThe FOA-60Q is the FOA-60's Ortho Apochromat objective with the 1.7x EX extender built permanently into the optical path — a 6-element, 4-group design running natively at 900 mm and f\/15, with an 88 mm corrected image circle. Takahashi publishes a theoretical Strehl ratio of 99.8% for this configuration, a figure the company states exceeds its own TOA-130 and TOA-150 triplets. The tube weighs 2.1 kg and extends to 707 mm.\u003c\/p\u003e\u003ch3\u003e\u003cstrong\u003eWho It's For\u003c\/strong\u003e\u003c\/h3\u003e\u003cp\u003eThis is a good match if you want the FOA-60's correction quality at long focal length without assembling the extender yourself — planetary and lunar observers chasing fine detail at high power, and double-star observers splitting close, faint pairs where wavefront quality matters as much as aperture. It suits imagers doing high-resolution planetary and lunar work who want a compact, dedicated long-focal-length apochromat rather than a general-purpose wide-field tube.\u003c\/p\u003e\u003ch3\u003e\u003cstrong\u003eKey Features \u0026amp; Design\u003c\/strong\u003e\u003c\/h3\u003e\u003cul\u003e\n\u003cli\u003e\n\u003cstrong\u003eOrtho Apochromat with built-in extender:\u003c\/strong\u003e six elements in four groups — the FOA-60 doublet plus a permanently mounted 1.7x extender group.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003e900 mm at f\/15:\u003c\/strong\u003e native focal length and ratio, with an 88 mm corrected image circle.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003e99.8% theoretical Strehl ratio,\u003c\/strong\u003e per Takahashi — correction Takahashi states exceeds its TOA-130 and TOA-150 triplets.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003e208.1 mm of back focus:\u003c\/strong\u003e ample room for a diagonal or imaging train.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003e84 mm drawtube extension\u003c\/strong\u003e on a rack-and-pinion focuser.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003e2.1 kg:\u003c\/strong\u003e compact for the focal length, in a tube that extends to 707 mm.\u003c\/li\u003e\n\u003c\/ul\u003e\u003ch3\u003e\u003cstrong\u003eOptical \/ Mechanical Design\u003c\/strong\u003e\u003c\/h3\u003e\u003cp\u003eThe front two elements are the FOA-60's Ortho Apochromat fluorite doublet — already specified for correction levels associated with Takahashi's TOA triplets — with a four-element 1.7x extender group permanently mated behind it, rather than sold as a separate accessory. The combination is what produces the published 99.8% theoretical Strehl ratio, and Takahashi's own comparison places that figure above the TOA-130 and TOA-150.\u003c\/p\u003e\u003cp\u003eHard multicoatings protect the fluorite surfaces, and the 208.1 mm of back focus — generous for a 60 mm-aperture tube — is what makes room for a diagonal, filter wheel or high-resolution planetary camera without running short on drawtube travel. Because the extender is integrated rather than an add-on, there is no shorter native configuration on this tube — removing the extender group returns it to a standard FOA-60.\u003c\/p\u003e\u003ch3\u003e\u003cstrong\u003eRecommended Uses\u003c\/strong\u003e\u003c\/h3\u003e\u003cul\u003e\n\u003cli\u003e\n\u003cstrong\u003eHigh-power planetary and lunar observing:\u003c\/strong\u003e at 900 mm and f\/15, where the high Strehl ratio shows up as tighter, cleaner diffraction detail.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eClose double-star splitting:\u003c\/strong\u003e correction quality matters as much as aperture for faint, tight pairs.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eHigh-resolution planetary imaging:\u003c\/strong\u003e the long native focal length suits lucky-imaging style planetary cameras without an additional Barlow.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eCompact long-focal-length visual work:\u003c\/strong\u003e 900 mm in a tube that still travels, at 2.1 kg.\u003c\/li\u003e\n\u003c\/ul\u003e\u003ch3\u003e\u003cstrong\u003eCompatibility and Accessory Notes\u003c\/strong\u003e\u003c\/h3\u003e\u003cp\u003eThe FOA-60Q's system chart and extender-specific chart, both in the Downloads tab, list the adapters and distances Takahashi publishes for this configuration. Our \u003ca href=\"\/pages\/takahashi-back-focus-guide\"\u003eTakahashi Back Focus Guide\u003c\/a\u003e collects the same figures for the whole Takahashi range.\u003c\/p\u003e\u003cul\u003e\n\u003cli\u003e\n\u003cstrong\u003eBack focus:\u003c\/strong\u003e 208.1 mm.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eImage circle:\u003c\/strong\u003e 88 mm, corrected.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eVisual train:\u003c\/strong\u003e a 1.25-inch or 2-inch diagonal and eyepiece attach through the matching Takahashi visual adapter.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eMount:\u003c\/strong\u003e sold as an OTA — no mount, rings, finder or dovetail included. At 2.1 kg it suits small to mid-sized equatorial mounts, though 900 mm of focal length asks more of tracking accuracy than a wide-field scope.\u003c\/li\u003e\n\u003c\/ul\u003e\u003cp\u003eIf you are planning a planetary imaging train and want to confirm your camera's back focus, send us the details and we will work it out with you.\u003c\/p\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 an optical tube assembly.\u003c\/strong\u003e Mount, tripod, rings, dovetail, diagonal, eyepiece and finder are sold separately.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eThe extender is built in, not removable as a separate accessory purchase.\u003c\/strong\u003e There is no shorter native configuration on this specific tube listing — for that, the FOA-60 without the extender is the base model.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003e60 mm still sets the light grasp.\u003c\/strong\u003e The Ortho design and extender improve correction and reach, not aperture — its strength is planetary and double-star detail rather than faint deep-sky targets.\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 — at prime focus it is a diagonal and eyepiece and you are observing. The system chart in the Downloads tab lists the adapters and distances for imaging.\u003c\/p\u003e\u003cp\u003e\u003cstrong\u003eWhat is it best used for?\u003c\/strong\u003e\u003c\/p\u003e\u003cp\u003eHigh-power lunar and planetary observing and imaging, and close double-star splitting, where the 99.8% theoretical Strehl ratio is most visible.\u003c\/p\u003e\u003cp\u003e\u003cstrong\u003eWhat is the difference between the FOA-60 and FOA-60Q?\u003c\/strong\u003e\u003c\/p\u003e\u003cp\u003eThe FOA-60Q has the 1.7x extender permanently built into the optical path — 900 mm at f\/15 instead of the FOA-60's native 530 mm at f\/8.8 — rather than being added as a separate accessory.\u003c\/p\u003e\u003cp\u003e\u003cstrong\u003eDoes it need additional accessories for imaging?\u003c\/strong\u003e\u003c\/p\u003e\u003cp\u003eThe 88 mm image circle and 208.1 mm of back focus are already corrected for this configuration; a planetary or lunar camera attaches through the standard visual train without an additional flattener.\u003c\/p\u003e\u003cp\u003e\u003cstrong\u003eWill it work on a small mount?\u003c\/strong\u003e\u003c\/p\u003e\u003cp\u003eAt 2.1 kg the tube is light, but 900 mm of focal length benefits from steady tracking. Tell us which mount you are using and we will confirm the fit.\u003c\/p\u003e\u003ch3\u003e\u003cstrong\u003eBottom Line\u003c\/strong\u003e\u003c\/h3\u003e\u003cp\u003eIn short: a 60 mm fluorite Ortho Apochromat running natively at 900 mm and f\/15, with an 88 mm image circle, 208.1 mm of back focus, and a published 99.8% theoretical Strehl ratio built for high-resolution planetary and lunar work.\u003c\/p\u003e","brand":"Takahashi","offers":[{"title":"Default Title","offer_id":54047056986223,"sku":"TAK-TFA06110","price":2373.8,"currency_code":"CAD","in_stock":false}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0686\/0049\/6239\/files\/TFA06110_FOA-60Q_OTA_1.jpg?v=1786912003","url":"https:\/\/ontariotelescope.com\/products\/takahashi-foa-60q-60mm-f-15-ortho-apochromatic-refractor-ota","provider":"Ontario Telescope and Accessories","version":"1.0","type":"link"}