{"product_id":"orion-optics-uk-85mm-fixed-adaptor-ring-15mm-bfd","title":"Orion Optics UK 85mm Fixed Adaptor Ring - 15mm BFD","description":"\u003cul class=\"DAV-feature-list\"\u003e\n\u003cli\u003e85mm Connection Diameter\u003c\/li\u003e\n\u003cli\u003eProvides 15mm of Fixed Back Focus\u003c\/li\u003e\n\u003cli\u003eCNC-Machined for Rigidity\u003c\/li\u003e\n\u003cli\u003eDesigned for Orion Optics UK Imaging Trains\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003c!-- more --\u003e\n\u003cul class=\"tabs\"\u003e\n\u003cli class=\"active\"\u003eDescription\u003c\/li\u003e\n\u003cli\u003eFAQ\u003c\/li\u003e\n\u003cli\u003eSpecifications\u003c\/li\u003e\n\u003cli\u003eIn the Box\u003c\/li\u003e\n\u003cli\u003eWarranty\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003cul class=\"tabs-content\"\u003e\n\u003cli class=\"active\"\u003e\n\u003cdiv\u003e\n\u003cdiv class=\"DAV-bg-light\"\u003e\n\u003cdiv class=\"DAV-section-center\"\u003e\n\u003ch2\u003eOrion Optics UK 85mm Fixed Adaptor Ring - 15mm BFD\u003c\/h2\u003e\n\u003cp\u003eThe Orion Optics UK 85mm fixed adaptor ring is a precision-machined component that establishes a rigid 15mm back focus distance (BFD) in your imaging train. This single-piece solution is engineered to eliminate the potential for tilt and flexure common with stacked or adjustable spacers, ensuring your camera sensor is perfectly orthogonal to the optical axis.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-bg-light\"\u003e\n\u003cdiv class=\"DAV-section\"\u003e\n\u003ch3\u003ePrecise 15mm Spacing for Correctors and Imagers\u003c\/h3\u003e\n\u003cp\u003eAchieving the exact back focus specified by a field flattener or coma corrector is critical for sharp, round stars across the entire image frame. This 85mm fixed adaptor creates exactly 15mm of spacing, removing the guesswork from your setup. It provides a solid, repeatable connection between your Orion Optics UK corrector and your imaging camera for consistent, high-fidelity results.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003c\/div\u003e\n\u003c\/div\u003e\n\u003c\/li\u003e\n\u003cli\u003e\n\u003cdiv class=\"DAV-accordion\"\u003e\n\u003ch3 class=\"DAV-accordion-Q\"\u003eWhat is the purpose of the Orion Optics UK 85mm fixed adaptor ring?\u003c\/h3\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion-A\"\u003e\n\u003cp\u003eThis adaptor sets a precise, fixed spacing of \u003cstrong\u003e15mm\u003c\/strong\u003e between two components in an optical train, typically a coma corrector or field flattener and an imaging camera. Using a fixed spacer is essential for achieving the optimal performance from your telescope's optics.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion\"\u003e\n\u003ch3 class=\"DAV-accordion-Q\"\u003eWhat does \"15mm BFD\" mean for this adaptor?\u003c\/h3\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion-A\"\u003e\n\u003cp\u003e\u003cstrong\u003eBFD\u003c\/strong\u003e stands for Back Focus Distance. This adaptor provides a fixed mechanical spacing of exactly 15mm, contributing to the total back focus requirement of your specific optical system.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion\"\u003e\n\u003ch3 class=\"DAV-accordion-Q\"\u003eWhy use this fixed 15mm BFD adaptor instead of an adjustable one?\u003c\/h3\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion-A\"\u003e\n\u003cp\u003eFixed adaptors offer superior rigidity and repeatability. They eliminate the possibility of tilt or flexure that can occur with adjustable spacers, ensuring a perfectly solid and orthogonal connection that maintains collimation and optical alignment.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion\"\u003e\n\u003ch3 class=\"DAV-accordion-Q\"\u003eWill this 85mm adaptor fit my telescope's focuser?\u003c\/h3\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion-A\"\u003e\n\u003cp\u003eThe \u003cstrong\u003e85mm\u003c\/strong\u003e dimension refers to the specific thread or flange diameter this ring is designed to connect with, which is common on certain large-format Orion Optics UK focusers and correctors. You must verify that the components you intend to connect have a matching 85mm interface before purchasing.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion\"\u003e\n\u003ch3 class=\"DAV-accordion-Q\"\u003eMy corrector needs 55mm of back focus. Can I use this Orion Optics UK 15mm adaptor?\u003c\/h3\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion-A\"\u003e\n\u003cp\u003eYes, but only as part of a complete spacing solution. This ring provides exactly 15mm of the total 55mm required. You would need to combine it with other spacers (e.g., a 40mm spacer) to achieve the full distance from the corrector's flange to the camera sensor.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion\"\u003e\n\u003ch3 class=\"DAV-accordion-Q\"\u003eIs this Orion Optics UK adaptor threaded?\u003c\/h3\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion-A\"\u003e\n\u003cp\u003eYes, as a dedicated adaptor ring, it is designed to thread securely onto other components. However, the specific thread pitch (e.g., M85x1) is not specified, so you should confirm compatibility with the Orion Optics UK components you intend to use it with.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003c\/li\u003e\n\u003cli\u003e\n\u003ctable class=\"DAV-specifications\"\u003e\n\u003ctbody\u003e\n\u003ctr\u003e\n\u003ctd\u003eAdapter Type\u003c\/td\u003e\n\u003ctd\u003eFixed Spacer Ring\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eInterface Diameter\u003c\/td\u003e\n\u003ctd\u003e85mm\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eProvided Back Focus\u003c\/td\u003e\n\u003ctd\u003e15mm\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eManufacturer\u003c\/td\u003e\n\u003ctd\u003eOrion Optics UK\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003c\/tbody\u003e\n\u003c\/table\u003e\n\u003c\/li\u003e\n\u003cli\u003e\n\u003cul class=\"DAV-grid\"\u003e\n\u003cli class=\"DAV-grid-item\"\u003e\n\u003cdiv\u003e\n\u003cp class=\"DAV-item-title\"\u003e85mm Fixed Adaptor Ring (15mm BFD)\u003c\/p\u003e\n\u003cp class=\"DAV-item-subtitle\"\u003e× 1\u003c\/p\u003e\n\u003c\/div\u003e\n\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003c\/li\u003e\n\u003cli\u003e\n\u003ca href=\"https:\/\/davidastro.com\/pages\/orion-optics-uk-warranty-policy\" rel=\"noopener\" target=\"_blank\"\u003eOrion Optics UK 1-Year Warranty\u003c\/a\u003e\n\u003c\/li\u003e\n\u003c\/ul\u003e","brand":"Orion Optics UK","offers":[{"title":"Default Title","offer_id":52942412808477,"sku":"OOUK-85MM-FIXED-ADAPTOR-RING-15MM","price":141.11,"currency_code":"USD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0753\/5280\/1565\/files\/Orion-Optics-UK-Logo_8571e988-2f1b-4418-8f01-58cd3cfdb82b.jpg?v=1789607534","url":"https:\/\/davidastro.com\/fr-us\/products\/orion-optics-uk-85mm-fixed-adaptor-ring-15mm-bfd","provider":"David Astro","version":"1.0","type":"link"}