{"product_id":"svbony-f9160a-m42-extension-tube-kit","title":"SVBONY M42x0.75 Extension Tube Kit (5, 10, 15, 20 mm)","description":"\u003cp\u003e\u003cimg src=\"https:\/\/cdn.shopify.com\/s\/files\/1\/0686\/0049\/6239\/files\/6385872860853407826523793.jpg?v=1791669946\" alt=\"SVBONY F9160A M42x0.75 extension tube kit overview\" style=\"max-width:100%;height:auto;\"\u003e\u003c\/p\u003e\u003ch3\u003e\u003cstrong\u003eProduct Overview\u003c\/strong\u003e\u003c\/h3\u003e\u003cp\u003eThe SVBONY F9160A is a set of four M42 x 0.75 extension tubes, 5 mm, 10 mm, 15 mm and 20 mm long. Each has a male and a female M42 x 0.75 thread, so they stack in any combination to add the spacing an imaging train needs, whether to set the backfocus behind a field flattener or reducer, or to adjust image scale. The tubes are all metal, anodized aluminium.\u003c\/p\u003e\u003ch3\u003e\u003cstrong\u003eWho It's For\u003c\/strong\u003e\u003c\/h3\u003e\u003cp\u003eThis is a good match if you image with an M42 (T2) camera train and need to fine-tune the distance between a corrector and your sensor, or to reach focus with a particular camera and adapter combination.\u003c\/p\u003e\u003ch3\u003e\u003cstrong\u003eKey Features \u0026amp; Design\u003c\/strong\u003e\u003c\/h3\u003e\u003cul\u003e\n\u003cli\u003e\n\u003cstrong\u003eFour lengths:\u003c\/strong\u003e 5, 10, 15 and 20 mm, used singly or combined (one, two or three at a time).\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eM42 x 0.75 male and female threads:\u003c\/strong\u003e the T2 standard, so they fit any M42 x 0.75 camera adapter.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eChainable:\u003c\/strong\u003e stack with other M42 x 0.75 parts to reach the length you need.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eAll-metal, anodized aluminium:\u003c\/strong\u003e resists deformation and keeps the train rigid.\u003c\/li\u003e\n\u003c\/ul\u003e\u003cp\u003e\u003cimg src=\"https:\/\/cdn.shopify.com\/s\/files\/1\/0686\/0049\/6239\/files\/6385872867345865996240512.jpg?v=1791669945\" alt=\"SVBONY F9160A extension tubes 5mm 10mm 15mm 20mm combined lengths\" style=\"max-width:100%;height:auto;\"\u003e\u003c\/p\u003e\u003cp\u003e\u003cimg src=\"https:\/\/cdn.shopify.com\/s\/files\/1\/0686\/0049\/6239\/files\/6385872873362403462965320.jpg?v=1791669946\" alt=\"SVBONY F9160A M42x0.75 male and female thread detail\" style=\"max-width:100%;height:auto;\"\u003e\u003c\/p\u003e\u003ch3\u003e\u003cstrong\u003eMechanical Design\u003c\/strong\u003e\u003c\/h3\u003e\u003cp\u003eFlatteners and reducers are designed to sit a specific distance from the sensor, usually stated as a backfocus figure such as 55 mm. That total is made up of the camera's own flange depth plus every adapter, filter holder and spacer in between. With these four tubes you can make up any length from 5 mm to 50 mm in 5 mm steps, which covers most of the gap left once your camera and adapters are counted.\u003c\/p\u003e\u003cp\u003e\u003cimg src=\"https:\/\/cdn.shopify.com\/s\/files\/1\/0686\/0049\/6239\/files\/6385872879774981005590239.jpg?v=1791669945\" alt=\"SVBONY F9160A all-metal anodized aluminium construction\" style=\"max-width:100%;height:auto;\"\u003e\u003c\/p\u003e\u003ch3\u003e\u003cstrong\u003eRecommended Uses\u003c\/strong\u003e\u003c\/h3\u003e\u003cul\u003e\n\u003cli\u003e\n\u003cstrong\u003eSetting backfocus\u003c\/strong\u003e behind a field flattener, reducer or coma corrector.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eReaching focus\u003c\/strong\u003e with cameras and adapters that sit too close to the focuser.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eAdjusting image scale\u003c\/strong\u003e where spacing changes magnification, such as behind a Barlow.\u003c\/li\u003e\n\u003c\/ul\u003e\u003cp\u003e\u003cimg src=\"https:\/\/cdn.shopify.com\/s\/files\/1\/0686\/0049\/6239\/files\/f9160a-2_20250807144920_6908.jpg?v=1791670273\" alt=\"SVBONY F9160A M42 extension tubes\" style=\"max-width:100%;height:auto;\"\u003e\u003c\/p\u003e\u003ch3\u003e\u003cstrong\u003eCompatibility and Accessory Notes\u003c\/strong\u003e\u003c\/h3\u003e\u003cul\u003e\n\u003cli\u003e\n\u003cstrong\u003eThread:\u003c\/strong\u003e M42 x 0.75 (T2) on both ends.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eWorks with:\u003c\/strong\u003e any M42 x 0.75 camera adapter, T-ring, corrector or astronomy camera.\u003c\/li\u003e\n\u003c\/ul\u003e\u003cp\u003eSend us your corrector and camera details and we will work out the spacer combination with you.\u003c\/p\u003e\u003ch3\u003e\u003cstrong\u003eWhat's in the Box\u003c\/strong\u003e\u003c\/h3\u003e\u003cp\u003eSVBONY describes the kit as four extension tubes: 5 mm, 10 mm, 15 mm and 20 mm.\u003c\/p\u003e\u003cp\u003e\u003cimg src=\"https:\/\/cdn.shopify.com\/s\/files\/1\/0686\/0049\/6239\/files\/f9160a-4_20250807144920_7713.jpg?v=1791670272\" alt=\"SVBONY F9160A M42 extension tube set\" style=\"max-width:100%;height:auto;\"\u003e\u003c\/p\u003e\u003ch3\u003e\u003cstrong\u003eGood to Know Before You Order\u003c\/strong\u003e\u003c\/h3\u003e\u003cul\u003e\n\u003cli\u003e\n\u003cstrong\u003eM42 x 0.75 only:\u003c\/strong\u003e for M48 trains, M48 spacers are needed.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eWeight:\u003c\/strong\u003e SVBONY does not publish a weight for this kit.\u003c\/li\u003e\n\u003c\/ul\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. Add up your camera's flange depth and the adapters in your train, subtract from the corrector's backfocus figure, and thread in the tubes that make up the difference.\u003c\/p\u003e\u003cp\u003e\u003cstrong\u003eCan I use more than one tube at a time?\u003c\/strong\u003e\u003c\/p\u003e\u003cp\u003eYes. SVBONY designs them to be used singly or combined.\u003c\/p\u003e\u003cp\u003e\u003cstrong\u003eDo they fit T-rings?\u003c\/strong\u003e\u003c\/p\u003e\u003cp\u003eYes. They use the M42 x 0.75 (T2) thread used by T-rings.\u003c\/p\u003e\u003ch3\u003e\u003cstrong\u003eBottom Line\u003c\/strong\u003e\u003c\/h3\u003e\u003cp\u003eIn short: four anodized-aluminium M42 x 0.75 spacers, 5 to 20 mm, that combine to set backfocus and focus position in a T2 imaging train.\u003c\/p\u003e","brand":"SvBony","offers":[{"title":"Default Title","offer_id":67722260512879,"sku":"F9160A","price":26.21,"currency_code":"CAD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0686\/0049\/6239\/files\/f9160a-1_20250807144920_6447_20260820164417_4628.webp?v=1791670272","url":"https:\/\/ontariotelescope.com\/products\/svbony-f9160a-m42-extension-tube-kit","provider":"Ontario Telescope and Accessories","version":"1.0","type":"link"}