{"product_id":"william-optics-ad-m80tom54","title":"William Optics 30mm Flattener Adapter","description":"\u003cul class=\"DAV-feature-list\"\u003e\n\u003cli\u003e30mm Optical Length\u003c\/li\u003e\n\u003cli\u003eConnects M80 x 0.75 to M54 x 0.75 Threads\u003c\/li\u003e\n\u003cli\u003eFor William Optics Flat68III \u0026amp; Flat7A Flatteners\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\u003e30mm Flattener Adapter\u003c\/h2\u003e\n\u003cp\u003eThe 30mm Flattener Adapter establishes a precise 30 mm of optical length while converting the M80 x 0.75 thread on specific William Optics flatteners to the common M54 x 0.75 thread used by modern astronomy cameras and filter wheels.\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\u003e30mm M80-to-M54 Adapter for William Optics Flatteners\u003c\/h3\u003e\n\u003cp\u003eThis adapter is purpose-built to integrate William Optics Flat68III and Flat7A flatteners into modern imaging trains. By converting the flattener's native M80 x 0.75 output thread to the widely adopted M54 x 0.75 standard, it allows direct connection to most filter wheels, off-axis guiders, and dedicated astronomy cameras.\u003c\/p\u003e\n\u003cp\u003eThe fixed 30 mm optical length is a critical component for achieving the correct back focus distance. This rigid, machined spacer removes a common variable in spacing calculations, ensuring your sensor is positioned at the precise focal plane required for sharp stars across the entire field.\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 primary purpose of the 30mm Flattener Adapter?\u003c\/h3\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion-A\"\u003e\n\u003cp\u003eThis adapter serves two key functions: it converts the M80 x 0.75 thread from a compatible flattener to a more common M54 x 0.75 camera-side thread, and it adds exactly 30 mm of optical length to help achieve the correct back focus for your imaging system.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion\"\u003e\n\u003ch3 class=\"DAV-accordion-Q\"\u003eWhich William Optics flatteners is this 30mm adapter designed for?\u003c\/h3\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion-A\"\u003e\n\u003cp\u003eIt is specifically designed for use with the \u003cstrong\u003eWilliam Optics Flat68III\u003c\/strong\u003e and \u003cstrong\u003eFlat7A\u003c\/strong\u003e flatteners, matching their M80 x 0.75 output threads.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion\"\u003e\n\u003ch3 class=\"DAV-accordion-Q\"\u003eHow do I know if I need this 30mm adapter for my imaging train?\u003c\/h3\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion-A\"\u003e\n\u003cp\u003eYou need this adapter if your imaging train requires exactly 30 mm of spacing between your Flat68III or Flat7A flattener and your next M54-threaded accessory to achieve the total back focus distance. Always calculate your complete optical path length to confirm this component provides the correct spacing for your specific camera and accessories.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion\"\u003e\n\u003ch3 class=\"DAV-accordion-Q\"\u003eWhat are the exact thread sizes on the 30mm Flattener Adapter?\u003c\/h3\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion-A\"\u003e\n\u003cp\u003eThe adapter has female \u003cstrong\u003eM80 x 0.75\u003c\/strong\u003e threads on the telescope\/flattener side and male \u003cstrong\u003eM54 x 0.75\u003c\/strong\u003e threads on the camera side.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion\"\u003e\n\u003ch3 class=\"DAV-accordion-Q\"\u003eDoes this 30mm adapter affect the optical correction of my flattener?\u003c\/h3\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion-A\"\u003e\n\u003cp\u003eNo, the adapter contains no optical elements. It is a purely mechanical spacer designed to position your camera sensor at the correct distance where the flattener's optical correction is optimal. Using incorrect spacing will result in poor field correction and elongated stars.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion\"\u003e\n\u003ch3 class=\"DAV-accordion-Q\"\u003eCan I use this 30mm adapter with a filter wheel on my William Optics GT81 telescope?\u003c\/h3\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion-A\"\u003e\n\u003cp\u003eYes, this is a common application. If you are using a William Optics GT81 with a compatible flattener like the Flat68III, this 30mm adapter connects the flattener to an M54-threaded filter wheel. You must still account for the optical thickness of the filter wheel and any other spacers to ensure you hit the total required back focus distance.\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\u003eTelescope Side Thread\u003c\/td\u003e\n\u003ctd\u003eM80 x 0.75\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eCamera Side Thread\u003c\/td\u003e\n\u003ctd\u003eM54 x 0.75\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eOptical Length\u003c\/td\u003e\n\u003ctd\u003e30 mm\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\u003c\/ul\u003e\n\u003c\/li\u003e\n\u003cli\u003e\n\u003ca href=\"https:\/\/davidastro.com\/pages\/william-optics-warranty-policy\" rel=\"noopener\" target=\"_blank\"\u003eWilliam Optics 2-Year Warranty\u003c\/a\u003e\n\u003c\/li\u003e\n\u003c\/ul\u003e","brand":"William Optics","offers":[{"title":"Default Title","offer_id":52853690827037,"sku":"WO-AD-M80TOM54","price":80.0,"currency_code":"CAD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0753\/5280\/1565\/files\/WilliamOptics-30mm-Flattener-Adapter-1_c0c280c0-4536-4cdb-8419-22f1368313e5.jpg?v=1788457834","url":"https:\/\/davidastro.com\/products\/william-optics-ad-m80tom54","provider":"David Astro","version":"1.0","type":"link"}