{"product_id":"svbony-sv157-70mm-extension-tube-125in","title":"SVBONY SV157 70mm Extension Tube - 1.25\"","description":"\u003cul class=\"DAV-feature-list\"\u003e\n\u003cli\u003eAdds Critical Focuser Out-Travel\u003c\/li\u003e\n\u003cli\u003eStandard 1.25-inch Barrel Diameter\u003c\/li\u003e\n\u003cli\u003eImproves Focus for Astrophotography Cameras\u003c\/li\u003e\n\u003cli\u003eCNC-Machined Aluminum Construction\u003c\/li\u003e\n\u003cli\u003eSecure, No-Flex Connection\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\u003eSVBONY SV157 1.25-inch Extension Tube\u003c\/h2\u003e\n\u003cp\u003eThe SVBONY SV157 1.25-inch Extension Tube provides the critical extra length needed to bring cameras and certain eyepieces to a sharp image in a standard 1.25-inch focuser. This all-metal tube adds length to your optical path, solving common focus problems when your focuser runs out of outward travel, a frequent issue in both visual and photographic setups using 1.25-inch accessories.\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\u003eSolve Focuser Travel Issues for 1.25\" Accessories\u003c\/h3\u003e\n\u003cp\u003eIf you've ever tried to use a camera or a specific eyepiece and found you can't rack the focuser out far enough to achieve a sharp image, this is the solution. The SV157 Extension Tube fits directly into any standard 1.25-inch focuser or diagonal, instantly adding precious millimeters to your focus travel. It's an essential problem-solver for imagers using small planetary cameras and observers using eyepieces with an unusual focal plane.\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\u003eCNC-Machined Build: A Secure Fit for Your 1.25\" Optical Train\u003c\/h3\u003e\n\u003cp\u003eConstructed from a single piece of CNC-machined aluminum, the SV157 tube ensures a rigid and secure connection between your telescope and your accessory. The black anodized finish minimizes internal reflections, and the precise machining prevents sag or flexure that could tilt your camera sensor and ruin an image. This solid build maintains the integrity of your optical train for sharper, clearer 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\"\u003eWhen do I need an SVBONY SV157 1.25-inch Extension Tube?\u003c\/h3\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion-A\"\u003e\n\u003cp\u003eYou need an extension tube when your eyepiece or camera requires more \"out-travel\" than your telescope's focuser can provide. This often happens with Newtonian reflectors when imaging at prime focus, or with certain refractors when using specific diagonals or accessories. The \u003cstrong\u003eSVBONY SV157\u003c\/strong\u003e provides the extra length to push the focal plane outwards to meet your sensor or eyepiece.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion\"\u003e\n\u003ch3 class=\"DAV-accordion-Q\"\u003eHow does the SV157 Extension Tube help with astrophotography?\u003c\/h3\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion-A\"\u003e\n\u003cp\u003eAstrophotography cameras, especially small-format planetary or guide cameras, often have sensors that are recessed deep within their housing. This requires the telescope's focal plane to be positioned farther back than it would for a visual eyepiece. The \u003cstrong\u003eSV157 Extension Tube\u003c\/strong\u003e adds the necessary distance to achieve perfect focus on the camera sensor, which is critical for sharp images.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion\"\u003e\n\u003ch3 class=\"DAV-accordion-Q\"\u003eWill the SVBONY SV157 tube work with my 8\" f\/10 Schmidt-Cassegrain Telescope?\u003c\/h3\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion-A\"\u003e\n\u003cp\u003eYes, it is compatible. While Schmidt-Cassegrains (SCTs) typically have a very large range of focus travel, an extension tube like the \u003cstrong\u003eSVBONY SV157\u003c\/strong\u003e can still be useful. It allows you to position accessories like off-axis guiders or filter wheels at a specific distance without having to move the primary mirror to the extreme ends of its travel, which can sometimes introduce mirror shift.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion\"\u003e\n\u003ch3 class=\"DAV-accordion-Q\"\u003eCan I use the SVBONY SV157 Extension Tube with a Barlow lens?\u003c\/h3\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion-A\"\u003e\n\u003cp\u003eYes. Placing the \u003cstrong\u003eSV157 Extension Tube\u003c\/strong\u003e between a Barlow lens and an eyepiece will increase the magnification of the Barlow. This is a common technique for achieving very high magnifications for planetary imaging or observing, allowing you to fine-tune the effective focal length of your system.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion\"\u003e\n\u003ch3 class=\"DAV-accordion-Q\"\u003eIs the SVBONY SV157 Extension Tube threaded for 1.25\" filters?\u003c\/h3\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion-A\"\u003e\n\u003cp\u003eThe provided product data does not specify if the SV157 Extension Tube is threaded to accept standard 1.25-inch astronomy filters. Typically, extension tubes may or may not have these threads, so you should assume it is not threaded unless specified otherwise.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion\"\u003e\n\u003ch3 class=\"DAV-accordion-Q\"\u003eCould I use the SV157 to image the Moon with my short-tube refractor?\u003c\/h3\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion-A\"\u003e\n\u003cp\u003eAbsolutely. A short-tube refractor paired with a planetary camera is a classic setup where an extension tube is often required. The \u003cstrong\u003eSVBONY SV157\u003c\/strong\u003e will help you achieve the necessary back focus to get sharp, detailed images of lunar craters and maria with your 1.25-inch camera.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003c\/li\u003e\n\u003cli\u003e\n\u003ctable class=\"DAV-specifications\"\u003e\n\u003ctbody\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\n\u003cli\u003e\u003ca href=\"https:\/\/davidastro.com\/pages\/svbony-warranty-policy\" rel=\"noopener\" target=\"_blank\"\u003eSVBONY Warranty Policy\u003c\/a\u003e\u003c\/li\u003e\n\u003c\/ul\u003e","brand":"SVBONY","offers":[{"title":"Default Title","offer_id":52861243162909,"sku":"SV-W9118B","price":17.0,"currency_code":"CAD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0753\/5280\/1565\/files\/SVBONY-SV157-1-25inch-Extension-Tube-56mm-70mm-1-W9118B_d328ca6b-2e2b-4314-b54a-c297ca4b0c9f.jpg?v=1788660520","url":"https:\/\/davidastro.com\/fr\/products\/svbony-sv157-70mm-extension-tube-125in","provider":"David Astro","version":"1.0","type":"link"}