{"product_id":"william-optics-flt91-apo-triplet-refractor-space-gray","title":"William Optics FLT91 APO Triplet Refractor - Space Gray - T-FLT-91SG-RP33","description":"\u003ch3 style=\"text-align: center;\"\u003eWilliam Optics Fluorostar 91 Triplet Refractor in Space Gray\u003c\/h3\u003e\n\u003cp\u003eThis beautiful 91 mm f\/5.9 APO Triplet refractor is decked out and ready to ride on your telescope mount!  Whether you want to do visual astronomy, astrophotography, terrestrial observing or wildlife photography, this is the scope for you!  The FLT91 is designed from the optics down for a quality experience.  The optics are housed in a steel lens cell and consist of three elements (triplet) made of fully multi-coated Ohara FPL-53 glass.  Contrast, clarity and virtually color-free results will boost your visual and astro-imaging to a new level.\u003c\/p\u003e\n\u003cp\u003eThe 3.3-inch dual-speed rack \u0026amp; pinion focuser is built to hold the weight of a camera and other equipment, like the dedicated \u003ca href=\"https:\/\/khanscope.com\/products\/william-optics-flat6aiii-m92-0-8x-reducer-field-flattener-for-flt91-flat6aiii-m92\" title=\"William Optics FLT91 Field Flattener and 0.8X Reducer - FLAT6AIII-M92\" rel=\"noopener noreferrer\" target=\"_blank\"\u003eFLT91 0.8X Reducer and Field Flattener\u003c\/a\u003e, without flexing.  A super smooth field rotator is included to make it easier to frame the perfect shot, and it has markings every degree for repeatable results.  \u003c\/p\u003e\n\u003cp\u003eThe William Optics Rotolock goes way beyond your typical 2\" adapter, and will provide a very solid connection, whether you insert a 2\" diagonal or other accessories.\u003c\/p\u003e\n\u003cp\u003eOn the front end of the FLT91 you will find a custom Bahtinov mask that is connected to the removable lens cover.  It is easy to reveal the mask for precision focusing and then store it away again in the lens cover until you need it again.\u003c\/p\u003e\n\u003cp\u003eYou will also receive beefy mounting rings that connect to an included (and matching!) Vixen-style dovetail plate.  The rings have a built-in handle\/saddle bar on top to make it easy to carry and set up your FLT91...William Optics has thought of everything!  If you'd like to ride a guide scope or finder on top, this patented saddle bar handle will accept the William Optics Uniguide as well as other Vixen-style finders or guidescopes.\u003c\/p\u003e\n\u003cp\u003eFinally, the William Optics FLT91 comes with a soft carry case, allowing you to protect your telescope when not in use or when traveling to the perfect dark-sky site or terrestrial wonder.  \u003c\/p\u003e\n\u003cp\u003e\u003cbr\u003e\u003c\/p\u003e\n\u003ch3 style=\"text-align: center;\"\u003e Technical Specifications\u003c\/h3\u003e\n\u003cp style=\"text-align: left;\"\u003e\u003cstrong\u003eLens Type:\u003c\/strong\u003e  Apochromatic Triplet Prime Lens\u003cbr data-mce-fragment=\"1\"\u003e\u003cstrong\u003eFocal Length:\u003c\/strong\u003e  540mm\u003cbr data-mce-fragment=\"1\"\u003e\u003cstrong\u003eAperture\u003c\/strong\u003e:  91mm\u003cbr data-mce-fragment=\"1\"\u003e\u003cstrong\u003eFocal Ratio\u003c\/strong\u003e:  f\/5.9\u003cbr data-mce-fragment=\"1\"\u003e\u003cstrong\u003eFocuser\u003c\/strong\u003e:  Dual Speed 3.3\" R\u0026amp;P Focuser\u003cbr data-mce-fragment=\"1\"\u003e\u003cstrong\u003eLens Material\u003c\/strong\u003e:  Ohara FPL-53\u003cbr data-mce-fragment=\"1\"\u003e\u003cstrong\u003eStrehl Ratio\u003c\/strong\u003e:  0.95+\u003cbr data-mce-fragment=\"1\"\u003e\u003cstrong\u003eCamera Format\u003c\/strong\u003e:  Full Frame DSLR \/ Mirrorless \/ CMOS \/ CCD\u003cbr data-mce-fragment=\"1\"\u003e\u003cstrong\u003eRetracted Length\u003c\/strong\u003e:  441mm\u003cbr data-mce-fragment=\"1\"\u003e\u003cstrong\u003eExtended Length\u003c\/strong\u003e:  510mm\u003cbr data-mce-fragment=\"1\"\u003e\u003cstrong\u003eExtension Tube Length\u003c\/strong\u003e:  40mm\u003cbr data-mce-fragment=\"1\"\u003e\u003cstrong\u003eOTA Weight\u003c\/strong\u003e:  4.165Kg\u003cbr data-mce-fragment=\"1\"\u003e\u003cstrong\u003eTotal Weight\u003c\/strong\u003e:  5.575Kg\u003cbr data-mce-fragment=\"1\"\u003e\u003cstrong\u003eExtension Tube Weight\u003c\/strong\u003e:  0.105Kg\u003c\/p\u003e","brand":"William Optics","offers":[{"title":"Default Title","offer_id":39415200153713,"sku":"WIL-T-FLT-91SG-RP33","price":1945.95,"currency_code":"EUR","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0851\/2766\/products\/flt91_White_Silver.jpg?v=1776458911","url":"https:\/\/khanscope.com\/en-fr\/products\/william-optics-flt91-apo-triplet-refractor-space-gray","provider":"Khan Scope Centre","version":"1.0","type":"link"}