{"product_id":"takahashi-fc-35-0-66x-reducer-for-fc-fs-series","title":"Takahashi FC-35 0.66x Reducer for FC \/ FS Series","description":"\u003ch3\u003e\u003cstrong\u003eProduct Overview\u003c\/strong\u003e\u003c\/h3\u003e\u003cp\u003eThe FC-35 is Takahashi's 0.66x reducer for the FC and FS series refractors. On the FC-100DF it produces a 480 mm focal length at f\/4.8, with a Ø44 mm image circle that covers a full-frame sensor. It was designed for digital imaging rather than adapted to it.\u003c\/p\u003e\u003cp\u003eEach compatible telescope reaches a different focal length behind it, and each requires its own \u003cstrong\u003eCA ring\u003c\/strong\u003e to set the correct backfocus. The CA ring is a separate purchase — see the table below for which one your telescope takes.\u003c\/p\u003e\u003ch3\u003e\u003cstrong\u003eWho It's For\u003c\/strong\u003e\u003c\/h3\u003e\u003cp\u003eThis is a good match if you image with an FC or FS series refractor and want a faster system with a flat field across a full-frame sensor.\u003c\/p\u003e\u003ch3\u003e\u003cstrong\u003eKey Features \u0026amp; Design\u003c\/strong\u003e\u003c\/h3\u003e\u003cul\u003e\n\u003cli\u003e\n\u003cstrong\u003e0.66x reduction:\u003c\/strong\u003e the FC-100DF goes to 480 mm at f\/4.8.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eØ44 mm image circle:\u003c\/strong\u003e covers a 35 mm full-frame sensor, and it is the same figure on every compatible model.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eSix compatible telescopes:\u003c\/strong\u003e FC-100DF, FC-100, FS-102, FC-125, FS-128 and FS-152.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eModel-specific CA ring:\u003c\/strong\u003e sets backfocus for your particular telescope. Sold separately.\u003c\/li\u003e\n\u003c\/ul\u003e\u003ch3\u003e\u003cstrong\u003eOptical \/ Mechanical Design\u003c\/strong\u003e\u003c\/h3\u003e\u003cp\u003eA reducer shortens the effective focal length and speeds up the focal ratio — the same target in less exposure time, over a wider field. What separates a good one from a poor one is what happens away from the optical axis: reduction tends to introduce field curvature and enlarge star images at the edges. The Ø44 mm image circle is the answer here, and it holds across all six compatible telescopes rather than shrinking on the longer ones.\u003c\/p\u003e\u003cp\u003eThe CA ring is what makes one reducer serve six telescopes. Each model presents its optics at a different distance from the focal plane, so the ring — in 100D, 102 or 130 form — sets the spacing correctly for that tube. Get the ring right and the reducer performs as specified; use the wrong one and the corner stars are where it shows.\u003c\/p\u003e\u003ch3\u003e\u003cstrong\u003eRecommended Uses\u003c\/strong\u003e\u003c\/h3\u003e\u003cp\u003eWide-field deep-sky astrophotography on an FC or FS refractor — large nebulae, extended galaxies, and mosaic panels where the extra field and the faster ratio both count.\u003c\/p\u003e\u003ch3\u003e\u003cstrong\u003eCompatibility and Accessory Notes\u003c\/strong\u003e\u003c\/h3\u003e\u003ctable\u003e\n\u003ctr\u003e\n\u003cth\u003eTelescope\u003c\/th\u003e\n\u003cth\u003eFocal length\u003c\/th\u003e\n\u003cth\u003eFocal ratio\u003c\/th\u003e\n\u003cth\u003eCA ring required\u003c\/th\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eFC-100DF\u003c\/td\u003e\n\u003ctd\u003e480mm\u003c\/td\u003e\n\u003ctd\u003ef\/4.8\u003c\/td\u003e\n\u003ctd\u003e100D\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eFC-100\u003c\/td\u003e\n\u003ctd\u003e530mm\u003c\/td\u003e\n\u003ctd\u003ef\/5.3\u003c\/td\u003e\n\u003ctd\u003e102\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eFS-102\u003c\/td\u003e\n\u003ctd\u003e545mm\u003c\/td\u003e\n\u003ctd\u003ef\/5.3\u003c\/td\u003e\n\u003ctd\u003e102\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eFC-125\u003c\/td\u003e\n\u003ctd\u003e670mm\u003c\/td\u003e\n\u003ctd\u003ef\/5.4\u003c\/td\u003e\n\u003ctd\u003e130\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eFS-128\u003c\/td\u003e\n\u003ctd\u003e700mm\u003c\/td\u003e\n\u003ctd\u003ef\/5.5\u003c\/td\u003e\n\u003ctd\u003e130\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eFS-152\u003c\/td\u003e\n\u003ctd\u003e820mm\u003c\/td\u003e\n\u003ctd\u003ef\/5.4\u003c\/td\u003e\n\u003ctd\u003e130\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003c\/table\u003e\u003cp\u003eWe stock the Takahashi CA rings. Tell us which telescope and camera you are pairing this with and we will send the matching ring alongside it, so the train is complete when it arrives.\u003c\/p\u003e\u003ch3\u003e\u003cstrong\u003eGood to Know Before You Order\u003c\/strong\u003e\u003c\/h3\u003e\u003cp\u003e\u003cstrong\u003eThe CA ring is a separate item:\u003c\/strong\u003e Takahashi supplies the reducer on its own, and the ring that sets backfocus for your telescope is bought with it. We will pair them for you — just tell us the model.\u003c\/p\u003e\u003cp\u003e\u003cstrong\u003eAn imaging corrector, not a visual one:\u003c\/strong\u003e the FC-35 is designed for a camera at the focal plane and has no application in a visual train with an eyepiece.\u003c\/p\u003e\u003cp\u003e\u003cstrong\u003eThe ring is telescope-specific:\u003c\/strong\u003e 100D for the FC-100DF, 102 for the FC-100 and FS-102, 130 for the FC-125, FS-128 and FS-152.\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 — the CA ring does the work of setting the spacing for your telescope, so once you have the right ring it threads together directly. Getting the right ring is the step to take care over, and we will confirm it with you.\u003c\/p\u003e\u003cp\u003e\u003cstrong\u003eWhat does it do to my focal length?\u003c\/strong\u003e\u003c\/p\u003e\u003cp\u003eReduces it by roughly a third. On the FC-100DF that is 480 mm at f\/4.8.\u003c\/p\u003e\u003cp\u003e\u003cstrong\u003eWill it cover a full-frame camera?\u003c\/strong\u003e\u003c\/p\u003e\u003cp\u003eYes — the Ø44 mm image circle covers a 35 mm full-frame sensor.\u003c\/p\u003e\u003cp\u003e\u003cstrong\u003eIs the CA ring included?\u003c\/strong\u003e\u003c\/p\u003e\u003cp\u003eNo. Takahashi sells the ring separately and it is specific to your telescope. We stock them and will pair the right one with your order.\u003c\/p\u003e\u003cp\u003e\u003cstrong\u003eWhich telescopes does it fit?\u003c\/strong\u003e\u003c\/p\u003e\u003cp\u003eThe FC-100DF, FC-100, FS-102, FC-125, FS-128 and FS-152.\u003c\/p\u003e\u003ch3\u003e\u003cstrong\u003eBottom Line\u003c\/strong\u003e\u003c\/h3\u003e\u003cp\u003eA 0.66x reducer that turns an FC or FS refractor into a fast, flat, full-frame imaging system — 480 mm at f\/4.8 on the FC-100DF, with the matching CA ring ordered alongside it.\u003c\/p\u003e","brand":"Takahashi","offers":[{"title":"Default Title","offer_id":54086044319855,"sku":"TAK-TKA19580","price":1255.0,"currency_code":"CAD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0686\/0049\/6239\/files\/reducer_2_6.jpg?v=1787328854","url":"https:\/\/ontariotelescope.com\/products\/takahashi-fc-35-0-66x-reducer-for-fc-fs-series","provider":"Ontario Telescope and Accessories","version":"1.0","type":"link"}