{"product_id":"m42-spacer-ring-kit","title":"Celestron M42 Spacer Ring Kit","description":"\u003cp\u003e\u003cspan\u003eTo achieve the best astroimages, it is important to attain the proper back-focus distance for your camera relative to the telescope it is being used with. If the back-focus distance your camera consumes is not exact, the performance at the corners of full frame imaging sensors will suffer—stars will appear elongated and not as pinpoints.\u003c\/span\u003e\u003cbr\u003e\u003cspan\u003eExample: RASA 8 with a ZWO ASI 183 MC PRO camera\u003c\/span\u003e\u003c\/p\u003e\n\u003cul\u003e\n\u003cli\u003eRequired back-focus distance for RASA 8 with included M42 camera adapter: 25mm\u003c\/li\u003e\n\u003cli\u003eBack-focus consumed by ZWO ASI 183 MC PRO camera: 17.5mm\u003c\/li\u003e\n\u003cli\u003eTo achieve equal back-focus distance, a 7.5mm M42 spacer ring is required\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003cp\u003e \u003cbr\u003eCelestron’s M42 Spacer Ring kit includes three different length spacer rings to achieve the proper back-focus distance with our popular Celestron optical tubes and T-thread camera adapters.\u003cbr\u003e \u003cbr\u003e\u003cstrong\u003eHow to Use\u003c\/strong\u003e\u003cbr\u003eDepending your method of astrophotography (DSLR or CCD\/CMOS), there are two ways to use the M42 Spacer Ring. If you are using a DSLR, place the desired M42 Spacer Ring between your T-Ring and your T-Adapter for your optical tube. If you are using a CCD or CMOS camera, place the desired M42 Spacer Ring between the camera and the T-Adapter for your optical tube.\u003c\/p\u003e\n\u003cp\u003e\u003cbr\u003eBelow is a quick guide to help you determine which spacer ring to use for our EdgeHD, Schmidt-Cassegrain, and RASA 8 optical tubes:\u003c\/p\u003e\n\u003ctable class=\"compatibility-table\"\u003e\n\u003ctbody\u003e\n\u003ctr\u003e\n\u003ctd\u003eSpacer Ring Size:\u003c\/td\u003e\n\u003ctd\u003eWorks best with:\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003e7.5mm\u003c\/td\u003e\n\u003ctd\u003eProvides proper spacing with\u003cspan\u003e \u003c\/span\u003e\u003cstrong\u003eRASA 8\u003c\/strong\u003e\u003cspan\u003e \u003c\/span\u003efor many ZWO cameras\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003e12mm\u003c\/td\u003e\n\u003ctd\u003eProvides proper spacing with\u003cspan\u003e \u003c\/span\u003e\u003cstrong\u003eRASA 8\u003c\/strong\u003e\u003cspan\u003e \u003c\/span\u003efor many Atik cameras\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003e30mm\u003c\/td\u003e\n\u003ctd\u003eConverts ZWO camera w\/filter slider to 55mm back-focus standard for use with\u003cspan\u003e \u003c\/span\u003e\u003cstrong\u003eSchmidt-Cassegrain \u0026amp; EdgeHD\u003c\/strong\u003e\n\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003c\/tbody\u003e\n\u003c\/table\u003e\n\u003cp\u003e\u003cbr\u003e\u003cstrong\u003eBody\u003c\/strong\u003e\u003cbr\u003e\u003cspan\u003eThe M42 Spacer Rings are machined aluminum black anodized. The internal surfaces are blackened and glare-threaded to provide the highest contrast. Each spacer ring has a knurled surface, providing a great gripping surface for threading\/unthreading. The M42 Spacer Rings are compatible with M42 x 0.75 (T-thread) camera adapters.\u003c\/span\u003e\u003c\/p\u003e\n\u003ctable class=\"table-open\" id=\"product-specs-list\"\u003e\n\u003cthead\u003e\n\u003ctr\u003e\n\u003cth\u003eGENERAL\u003c\/th\u003e\n\u003cth\u003e\u003c\/th\u003e\n\u003c\/tr\u003e\n\u003c\/thead\u003e\n\u003ctbody\u003e\n\u003ctr\u003e\n\u003ctd\u003eThread:\u003c\/td\u003e\n\u003ctd\u003eM42 x 0.75\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eSpacer lengths:\u003c\/td\u003e\n\u003ctd\u003e7.5mm (.29\"), 12mm (.47\"), and 30mm (1.18\")\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eConstruction:\u003c\/td\u003e\n\u003ctd\u003eAluminum black anodized\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eInterior:\u003c\/td\u003e\n\u003ctd\u003eBlackened and glare threaded\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eExterior:\u003c\/td\u003e\n\u003ctd\u003eKnurled grip surface, each ring labeled with its length\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003c\/tbody\u003e\n\u003c\/table\u003e\n\u003c!----\u003e","brand":"Celestron","offers":[{"title":"Default Title","offer_id":45299222380803,"sku":"93618","price":116.0,"currency_code":"AUD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0270\/1859\/files\/93618_M42_Spacer_Ring_Kit_01_570x380_2x_bf6c6eb7-e00f-45d5-849f-665a05542ed4.jpg?v=1761845299","url":"https:\/\/www.jacobsdigital.co.nz\/en-au\/products\/m42-spacer-ring-kit","provider":"Jacobs Digital","version":"1.0","type":"link"}