{"product_id":"svbony-sv119-m48-extension-tube-kit","title":"SVBONY SV119 M48 Extension Tube Kit (5, 10, 15, 30 mm)","description":"\u003cp\u003e\u003cimg src=\"https:\/\/cdn.shopify.com\/s\/files\/1\/0686\/0049\/6239\/files\/6385881672556518594748926.jpg?v=1791669841\" alt=\"SVBONY SV119 M48 extension tube kit key visual\" style=\"max-width:100%;height:auto;\"\u003e\u003c\/p\u003e\u003ch3\u003e\u003cstrong\u003eProduct Overview\u003c\/strong\u003e\u003c\/h3\u003e\u003cp\u003eThe SVBONY SV119 (item F9190A) is a set of M48×0.75 extension tubes in 5 mm, 10 mm, 15 mm and 30 mm lengths. Each tube has a male thread on one end and a female thread on the other, so they stack in any combination to add the spacing an imaging train needs behind a reducer, field flattener, corrector or Barlow. The tubes are fully anodized aluminium with an internally threaded bore to cut stray reflections, and SVBONY publishes a net weight of 72.9 g (2.57 oz).\u003c\/p\u003e\u003cp\u003e\u003cimg src=\"https:\/\/cdn.shopify.com\/s\/files\/1\/0686\/0049\/6239\/files\/6385881680597466602543051.jpg?v=1791669841\" alt=\"SVBONY SV119 four-tube kit combinations\" style=\"max-width:100%;height:auto;\"\u003e\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 through an M48 corrector and need to hit its published backfocus, or if you want a few spare lengths on hand to fine-tune focus position and image scale with a camera or eyepiece train.\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 30 mm, giving any combination from 5 mm to 60 mm in 5 mm steps.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eM48×0.75 male and female threads:\u003c\/strong\u003e the tubes stack directly onto each other and onto M48 accessories.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eInner-threaded bore:\u003c\/strong\u003e reduces stray light and internal reflections.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eAnodized aluminium:\u003c\/strong\u003e light, durable and black throughout.\u003c\/li\u003e\n\u003c\/ul\u003e\u003cp\u003e\u003cimg src=\"https:\/\/cdn.shopify.com\/s\/files\/1\/0686\/0049\/6239\/files\/6385881687888766214906316.jpg?v=1791669841\" alt=\"SVBONY SV119 M48x0.75 male and female threads\" 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\/6385881694465893014563095.jpg?v=1791669841\" alt=\"SVBONY SV119 inner threaded design\" 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\u003eBackfocus spacing\u003c\/strong\u003e behind M48 field flatteners, reducers and coma correctors.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eFocus reach:\u003c\/strong\u003e extending the train when a camera or eyepiece cannot reach focus.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eImage scale:\u003c\/strong\u003e changing the spacing behind a Barlow to adjust magnification.\u003c\/li\u003e\n\u003c\/ul\u003e\u003cp\u003e\u003cimg src=\"https:\/\/cdn.shopify.com\/s\/files\/1\/0686\/0049\/6239\/files\/6385881706129139591600771.jpg?v=1791669841\" alt=\"SVBONY SV119 anodized aluminium 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 M48×0.75 male and female on every tube.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eConnects:\u003c\/strong\u003e cameras, eyepiece adapters and other accessories with M48×0.75 threads.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eSpacing:\u003c\/strong\u003e add the tube lengths to your camera's sensor-to-flange distance and any filter drawer or wheel to reach your corrector's required backfocus. Send us your setup and we will work the figure out with you.\u003c\/li\u003e\n\u003c\/ul\u003e\u003ch3\u003e\u003cstrong\u003eWhat's in the Box\u003c\/strong\u003e\u003c\/h3\u003e\u003cul\u003e\n\u003cli\u003e5 mm M48 extension tube\u003c\/li\u003e\n\u003cli\u003e10 mm M48 extension tube\u003c\/li\u003e\n\u003cli\u003e15 mm M48 extension tube\u003c\/li\u003e\n\u003cli\u003e30 mm M48 extension tube\u003c\/li\u003e\n\u003c\/ul\u003e\u003ch3\u003e\u003cstrong\u003eGood to Know Before You Order\u003c\/strong\u003e\u003c\/h3\u003e\u003cul\u003e\n\u003cli\u003e\n\u003cstrong\u003eMechanical spacers only:\u003c\/strong\u003e they contain no glass and do not change focal length on their own.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eM48 only:\u003c\/strong\u003e an M42 (T2) train needs M42 tubes or an M48-to-M42 adapter.\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. Choose the lengths that add up to the spacing you need and thread them together between your corrector and camera.\u003c\/p\u003e\u003cp\u003e\u003cstrong\u003eWhat spacings can I make?\u003c\/strong\u003e\u003c\/p\u003e\u003cp\u003eAny 5 mm step from 5 mm to 60 mm using the four tubes.\u003c\/p\u003e\u003cp\u003e\u003cstrong\u003eDo they work with M42 cameras?\u003c\/strong\u003e\u003c\/p\u003e\u003cp\u003eNot directly. The tubes are M48×0.75 at both ends, so an M42 camera needs an M48-to-M42 adapter.\u003c\/p\u003e\u003ch3\u003e\u003cstrong\u003eBottom Line\u003c\/strong\u003e\u003c\/h3\u003e\u003cp\u003eIn short: four stackable M48×0.75 anodized aluminium spacers, 5 to 30 mm, for setting backfocus and focus position in an imaging train.\u003c\/p\u003e","brand":"SvBony","offers":[{"title":"Default Title","offer_id":67722206019695,"sku":"F9190A","price":29.63,"currency_code":"CAD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0686\/0049\/6239\/files\/f9190a-1_20250807144744_5131_20260810143936_0388.webp?v=1791670025","url":"https:\/\/ontariotelescope.com\/products\/svbony-sv119-m48-extension-tube-kit","provider":"Ontario Telescope and Accessories","version":"1.0","type":"link"}