{"product_id":"takahashi-fsq-80fc-80mm-f-5-6-quintuplet-astrograph-refractor-ota","title":"Takahashi FSQ-80FC 80mm f\/5.6 Quintuplet Astrograph Refractor OTA","description":"\u003ch3\u003e\u003cstrong\u003eProduct Overview\u003c\/strong\u003e\u003c\/h3\u003e\u003cp\u003eThe FSQ-80FC is Takahashi's compact 80 mm imaging refractor, built around a 5-element optical design with dual fluorite elements. At a native 450 mm focal length and f\/5.6, it is intended as a wide-field astrograph rather than a visual scope — the flat field and 50 mm image circle cover a full-frame sensor without a separate flattener. Takahashi lists a tube weight of approximately 4.1 kg.\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 a wide-field, grab-and-go imaging refractor that travels light — the compact tube and roughly 4.1 kg weight suit a smaller equatorial mount or a travel setup, and the flat 50 mm image circle covers full-frame sensors without an accessory flattener to buy separately.\u003c\/p\u003e\u003ch3\u003e\u003cstrong\u003eKey Features \u0026amp; Design\u003c\/strong\u003e\u003c\/h3\u003e\u003cul\u003e\n\u003cli\u003e\n\u003cstrong\u003e5-element optical design with dual fluorite elements:\u003c\/strong\u003e corrects chromatic aberration and field curvature within the tube, without a separate corrector.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003e450 mm focal length at f\/5.6:\u003c\/strong\u003e a fast, wide field of view suited to nebulae, star clusters and large-scale mosaic targets.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003e50 mm image circle:\u003c\/strong\u003e covers full-frame sensors with a flat field, as published by Takahashi.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eNative M48 interface with 55 mm back focus:\u003c\/strong\u003e supports direct camera attachment with minimal adapter stacking, reducing flexure in the imaging train.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eRetracting dew shield:\u003c\/strong\u003e tube length runs 486 mm retracted to 559 mm extended for storage and transport.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eRack-and-pinion focuser:\u003c\/strong\u003e holds a full imaging train of camera, filter wheel and guider.\u003c\/li\u003e\n\u003c\/ul\u003e\u003ch3\u003e\u003cstrong\u003eOptical \/ Mechanical Design\u003c\/strong\u003e\u003c\/h3\u003e\u003cp\u003eThe FSQ-80FC carries Takahashi's quintuplet Petzval-derived design — five elements including two fluorite lenses — aimed at flattening the field and correcting color across the frame without a separate flattener accessory. At f\/5.6 and 450 mm focal length it trades focal length for field width and speed, the combination astrographs are built around. The aluminum tube and fully multi-coated optics are typical of the FSQ line's imaging-first design; where Takahashi's other refractors are sold as visual-capable OTAs with an optional flattener, the FSQ-80FC's flattening is built into the base optical prescription.\u003c\/p\u003e\u003ch3\u003e\u003cstrong\u003eRecommended Uses\u003c\/strong\u003e\u003c\/h3\u003e\u003cp\u003eWide-field deep-sky astrophotography of nebulae, large star clusters and galaxy fields; full-frame mosaic imaging; travel and portable imaging rigs where tube weight and length matter.\u003c\/p\u003e\u003ch3\u003e\u003cstrong\u003eCompatibility and Accessory Notes\u003c\/strong\u003e\u003c\/h3\u003e\u003cp\u003eTakahashi publishes a 55 mm back focus from the native M48 interface, which is enough to seat most cooled cameras directly or with a thin adapter stack — filter wheels and off-axis guiders add up quickly against that figure, so it is worth checking your full imaging train before ordering.\u003c\/p\u003e\u003ch3\u003e\u003cstrong\u003eGood to Know Before You Order\u003c\/strong\u003e\u003c\/h3\u003e\u003cp\u003e\u003cstrong\u003ePublished weight is approximate:\u003c\/strong\u003e Takahashi's own listing states \"approx. 4.1 kg\" rather than an exact figure.\u003c\/p\u003e\u003cp\u003e\u003cstrong\u003eMount and tripod are not included:\u003c\/strong\u003e this listing is the optical tube assembly only.\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 flattening is built into the optics, so there is no separate corrector to thread on and space out. The M48 interface accepts a camera directly once your adapter stack is sorted.\u003c\/p\u003e\u003cp\u003e\u003cstrong\u003eWhat is it best used for?\u003c\/strong\u003e\u003c\/p\u003e\u003cp\u003eWide-field deep-sky astrophotography where a fast, short-focal-length refractor covers more sky per frame than a longer telescope.\u003c\/p\u003e\u003cp\u003e\u003cstrong\u003eCan I use it for visual observing?\u003c\/strong\u003e\u003c\/p\u003e\u003cp\u003eIt is built and marketed as an imaging astrograph; its native interface and back focus are set for a camera, not an eyepiece.\u003c\/p\u003e\u003cp\u003e\u003cstrong\u003eWhat cameras does it fit?\u003c\/strong\u003e\u003c\/p\u003e\u003cp\u003eAny camera that reaches the 55 mm back focus through the M48 interface, including full-frame cooled CMOS and CCD cameras — send us your camera and filter setup and we will work it out with you.\u003c\/p\u003e\u003cp\u003e\u003cstrong\u003eHow is this different from the FSQ-85EDX?\u003c\/strong\u003e\u003c\/p\u003e\u003cp\u003eThey are separate optical designs, each on its own specification sheet — figures for one do not describe the other.\u003c\/p\u003e\u003ch3\u003e\u003cstrong\u003eBottom Line\u003c\/strong\u003e\u003c\/h3\u003e\u003cp\u003eIn short: a compact 80 mm f\/5.6 quintuplet astrograph with a built-in flattener, a 50 mm image circle, and roughly 4.1 kg of travel-friendly weight, built for wide-field imaging over visual use.\u003c\/p\u003e","brand":"Takahashi","offers":[{"title":"Default Title","offer_id":54047049384047,"sku":"TAK-TQE08041","price":6263.4,"currency_code":"CAD","in_stock":false}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0686\/0049\/6239\/files\/fsq-80fc_-1-1024x576_jpg.png?v=1786911606","url":"https:\/\/ontariotelescope.com\/products\/takahashi-fsq-80fc-80mm-f-5-6-quintuplet-astrograph-refractor-ota","provider":"Ontario Telescope and Accessories","version":"1.0","type":"link"}