{"product_id":"baader-planetarium-tz-3s-telecentric-system-t-2-for-sundancer-ii-and-more","title":"Baader Planetarium TZ-3S Telecentric System T-2 for SunDancer II and more","description":"\u003cul class=\"DAV-feature-list\"\u003e\n\u003cli\u003e3x Achromatic Telecentric System\u003c\/li\u003e\n\u003cli\u003eDelivers a Parallel Light Beam for H-alpha Filters\u003c\/li\u003e\n\u003cli\u003eIlluminates a 27.5mm Image Circle\u003c\/li\u003e\n\u003cli\u003e96mm Working Distance from T-2 Thread Base\u003c\/li\u003e\n\u003cli\u003eDual 1.25\" and 2\" Nosepiece\u003c\/li\u003e\n\u003cli\u003eT-2 Thread for Secure Camera 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\u003eDownloads\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\u003eTZ-3S Telecentric System T-2 for SunDancer II and more\u003c\/h2\u003e\n\u003cp\u003eThe Baader TZ-3S is a 3x achromatic telecentric system engineered to deliver a perfectly parallel beam of light, a mandatory requirement for narrow-band H-alpha solar filters which must operate at a focal ratio of f\/30. This standalone version, identified by its gold anodized label, illuminates a 27.5mm image circle over a forgiving 96 mm working distance. With its versatile dual 1.25\"\/2\" nosepiece and secure T-2 camera-side thread, the TZ-3S serves as a high-contrast replacement for a standard Barlow lens for both critical solar and planetary imaging.\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\u003eThe 3x Telecentric Advantage: Parallel Light and Stable Magnification\u003c\/h3\u003e\n\u003cp\u003eUnlike a Barlow lens, which creates a diverging light cone and whose magnification changes with distance, a telecentric system produces parallel light rays. This core design principle ensures the magnification factor of the TZ-3S remains a constant 3x, regardless of where your camera or eyepiece is placed relative to its 96 mm optimal working distance. The result is a stable image scale and superior image quality, free from the optical compromises inherent in extending a Barlow's magnification with extension tubes.\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\u003eAchieving the Mandatory f\/30 for H-alpha Etalons\u003c\/h3\u003e\n\u003cp\u003eFor sub-Angstrom H-alpha filters like the Baader SunDancer II, a telecentric system is not an optional accessory—it is an essential prerequisite. These filters rely on an internal etalon that only performs to specification when fed a perfectly parallel beam of light at f\/30 or slower. Simply using a Barlow to increase a telescope's focal ratio to f\/30 does not create a parallel beam and will severely degrade the filter's contrast. The TZ-3S correctly converts a standard f\/10 telescope into an f\/30 instrument, ensuring the etalon performs at its maximum theoretical contrast.\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\u003eAchromatic Imaging: Illuminating a 27.5mm Image Circle\u003c\/h3\u003e\n\u003cp\u003eWhile designed for H-alpha, the TZ-3S is a fully achromatic system, corrected across the visible spectrum. This makes it a powerful tool for high-magnification lunar and planetary imaging, delivering higher contrast than simple Barlows or eyepiece projection. The system illuminates a 27.5mm image circle, making it an ideal match for the smaller sensors found in modern, high-speed planetary cameras that thrive at the high magnifications needed to resolve fine detail on Jupiter's cloud bands or the Cassini Division in Saturn's rings.\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\u003eMechanical Interface: Dual 1.25\"\/2\" Nosepiece and T-2 Threading\u003c\/h3\u003e\n\u003cp\u003eThe TZ-3S is built for secure, flex-free integration into any imaging train. On the telescope side, a dual-purpose nosepiece fits both 1.25\" and 2\" focusers and features safety kerfs instead of a simple groove, preventing tilts and ensuring a solid lock. On the camera side, a standard T-2 (M42x0.75) male thread provides a rigid, direct connection to cameras, filter wheels, and T-2 eyepiece holders, eliminating the potential for sag that can occur with simple thumbscrew connections.\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\u003eTZ-3S vs. TZ-4S: Matching f\/10 vs. f\/7.5 Telescopes\u003c\/h3\u003e\n\u003cp\u003eChoosing the correct telecentric depends on your telescope's native focal ratio. While the TZ-4S offers a larger 36mm clear aperture, its primary purpose is different.\u003c\/p\u003e\n\u003cul\u003e\n\u003cli\u003e\n\u003cstrong\u003eTZ-3S (Gold Label):\u003c\/strong\u003e This 3x telecentric is optimized for telescopes with a focal ratio of f\/10, converting them to the target f\/30 for H-alpha filters.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eTZ-4S (Violet Label):\u003c\/strong\u003e The 4x telecentric is designed for faster telescopes around f\/7.5, providing the necessary magnification to reach the same f\/30 target.\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003cp\u003eThis standalone TZ-3S does not include the 2nm blocking filter required for the SunDancer II system; that component is only integrated into the red-ring version sold with the filter itself.\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 main difference between the Baader TZ-3S Telecentric and a standard 3x Barlow lens?\u003c\/h3\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion-A\"\u003e\n\u003cp\u003eA Barlow lens creates a diverging light cone, and its magnification changes as you alter the distance to the camera sensor. The \u003cstrong\u003eTZ-3S Telecentric System\u003c\/strong\u003e produces a parallel beam of light, which means its \u003cstrong\u003e3x magnification factor and image quality remain constant\u003c\/strong\u003e regardless of the working distance. This parallel beam is also a mandatory requirement for the proper function of narrow-band H-alpha solar filters.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion\"\u003e\n\u003ch3 class=\"DAV-accordion-Q\"\u003eWhy is the TZ-3S Telecentric mandatory for a filter like the Baader SunDancer II?\u003c\/h3\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion-A\"\u003e\n\u003cp\u003eThe high-precision etalon inside a sub-Angstrom H-alpha filter requires a perfectly parallel, slow focal ratio (typically \u003cstrong\u003ef\/30\u003c\/strong\u003e) light beam to achieve its rated contrast and bandpass. Using a standard Barlow lens to reach f\/30 does not create a parallel beam and will significantly degrade the filter's performance. The TZ-3S is specifically designed to produce this parallel f\/30 beam, making it essential for critical solar observation.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion\"\u003e\n\u003ch3 class=\"DAV-accordion-Q\"\u003eCan I use the standalone TZ-3S for planetary imaging with my f\/10 SCT?\u003c\/h3\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion-A\"\u003e\n\u003cp\u003eYes, absolutely. The TZ-3S is an excellent choice for this application. Its achromatic design is corrected for the entire visible spectrum, and it provides higher contrast than most Barlows. On an f\/10 Schmidt-Cassegrain Telescope (SCT), it creates an f\/30 imaging system, which is ideal for capturing fine details on planets like Jupiter and Saturn with modern high-frame-rate cameras.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion\"\u003e\n\u003ch3 class=\"DAV-accordion-Q\"\u003eWill the TZ-3S work with my camera that has a sensor larger than 27.5mm?\u003c\/h3\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion-A\"\u003e\n\u003cp\u003eThe TZ-3S is optically designed to fully illuminate an image circle of \u003cstrong\u003e27.5mm\u003c\/strong\u003e in diameter. While you can use it with a camera that has a larger sensor (like APS-C), you will experience significant vignetting (darkening) at the corners and edges of the frame. It is best matched with sensors that fit within this image circle.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion\"\u003e\n\u003ch3 class=\"DAV-accordion-Q\"\u003eHow do I attach the TZ-3S to my telescope and camera?\u003c\/h3\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion-A\"\u003e\n\u003cp\u003eThe TZ-3S is very versatile. On the telescope side, it has a \u003cstrong\u003edual 1.25\" and 2\" nosepiece\u003c\/strong\u003e that slides directly into your focuser. On the camera side, it features a standard \u003cstrong\u003eT-2 (M42x0.75) male thread\u003c\/strong\u003e for a secure, threaded connection to your imaging camera, filter wheel, or a T-2 eyepiece clamp.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion\"\u003e\n\u003ch3 class=\"DAV-accordion-Q\"\u003eI have an f\/7.5 refractor. Should I use the TZ-3S or the TZ-4S for my H-alpha filter?\u003c\/h3\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion-A\"\u003e\n\u003cp\u003eFor an f\/7.5 telescope, the \u003cstrong\u003eTZ-4S (4x Telecentric) is the correct choice\u003c\/strong\u003e. To reach the required f\/30 focal ratio for an H-alpha filter, you need a 4x magnification factor (7.5 x 4 = 30). The TZ-3S would only bring your system to f\/22.5, which is too fast for the etalon to perform optimally.\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\u003eNet weight (kg)\u003c\/td\u003e\n\u003ctd\u003e0.17\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eBackfocus\u003c\/td\u003e\n\u003ctd\u003e96 mm distance to T-2 threaded base\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eBarrel Size (in)\u003c\/td\u003e\n\u003ctd\u003e1¼\", 2\"\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eOptical Design\u003c\/td\u003e\n\u003ctd\u003eTelecentric System\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eInner Diameter \/ Clear Aperture (mm)\u003c\/td\u003e\n\u003ctd\u003e27 mm\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eUsage\u003c\/td\u003e\n\u003ctd\u003efor H-alpha observation or as Barlow lens, with frame for the block filter of the Baader SunDancer II H-alpha filter\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eFocal length extension\u003c\/td\u003e\n\u003ctd\u003e3x\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eOuter Connection (eyepiece\/-camera-sided)\u003c\/td\u003e\n\u003ctd\u003eM42 x 0.75 (T-2)\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eOuter Connection (lens sided)\u003c\/td\u003e\n\u003ctd\u003eø 1¼\" (31.75 mm), ø 2\" (50.8mm)\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eImage Field\u003c\/td\u003e\n\u003ctd\u003e27 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\u003cul class=\"DAV-grid\"\u003e\n\u003cli class=\"DAV-grid-item\"\u003e\u003ca href=\"https:\/\/cdn.shopify.com\/s\/files\/1\/0753\/5280\/1565\/files\/Baader_Planetarium_SolarSpectrum_H-alpha_Filter_Telecentric_Systems_Manual.pdf\" target=\"_blank\"\u003e\u003csvg class=\"DAV-img-box\" viewbox=\"0 0 512 512\" xmlns=\"http:\/\/www.w3.org\/2000\/svg\"\u003e\u003cpath d=\"M0 64C0 28.7 28.7 0 64 0L224 0l0 128c0 17.7 14.3 32 32 32l128 0 0 144-208 0c-35.3 0-64 28.7-64 64l0 144-48 0c-35.3 0-64-28.7-64-64L0 64zm384 64l-128 0L256 0 384 128zM176 352l32 0c30.9 0 56 25.1 56 56s-25.1 56-56 56l-16 0 0 32c0 8.8-7.2 16-16 16s-16-7.2-16-16l0-48 0-80c0-8.8 7.2-16 16-16zm32 80c13.3 0 24-10.7 24-24s-10.7-24-24-24l-16 0 0 48 16 0zm96-80l32 0c26.5 0 48 21.5 48 48l0 64c0 26.5-21.5 48-48 48l-32 0c-8.8 0-16-7.2-16-16l0-128c0-8.8 7.2-16 16-16zm32 128c8.8 0 16-7.2 16-16l0-64c0-8.8-7.2-16-16-16l-16 0 0 96 16 0zm80-112c0-8.8 7.2-16 16-16l48 0c8.8 0 16 7.2 16 16s-7.2 16-16 16l-32 0 0 32 32 0c8.8 0 16 7.2 16 16s-7.2 16-16 16l-32 0 0 48c0 8.8-7.2 16-16 16s-16-7.2-16-16l0-64 0-64z\" fill=\"#0047a7\"\u003e\u003c\/path\u003e\u003c\/svg\u003e\n\u003cdiv\u003e\n\u003cp class=\"DAV-item-title\"\u003eBaader Planetarium SolarSpectrum H-alpha Filter Telecentric Systems Manual\u003c\/p\u003e\n\u003c\/div\u003e\n\u003c\/a\u003e\u003c\/li\u003e\n\u003cli class=\"DAV-grid-item\"\u003e\u003ca href=\"https:\/\/cdn.shopify.com\/s\/files\/1\/0753\/5280\/1565\/files\/Baader_Planetarium_SunDancer_II_H-alpha_Filter_Manual.pdf\" target=\"_blank\"\u003e\u003csvg class=\"DAV-img-box\" viewbox=\"0 0 512 512\" xmlns=\"http:\/\/www.w3.org\/2000\/svg\"\u003e\u003cpath d=\"M0 64C0 28.7 28.7 0 64 0L224 0l0 128c0 17.7 14.3 32 32 32l128 0 0 144-208 0c-35.3 0-64 28.7-64 64l0 144-48 0c-35.3 0-64-28.7-64-64L0 64zm384 64l-128 0L256 0 384 128zM176 352l32 0c30.9 0 56 25.1 56 56s-25.1 56-56 56l-16 0 0 32c0 8.8-7.2 16-16 16s-16-7.2-16-16l0-48 0-80c0-8.8 7.2-16 16-16zm32 80c13.3 0 24-10.7 24-24s-10.7-24-24-24l-16 0 0 48 16 0zm96-80l32 0c26.5 0 48 21.5 48 48l0 64c0 26.5-21.5 48-48 48l-32 0c-8.8 0-16-7.2-16-16l0-128c0-8.8 7.2-16 16-16zm32 128c8.8 0 16-7.2 16-16l0-64c0-8.8-7.2-16-16-16l-16 0 0 96 16 0zm80-112c0-8.8 7.2-16 16-16l48 0c8.8 0 16 7.2 16 16s-7.2 16-16 16l-32 0 0 32 32 0c8.8 0 16 7.2 16 16s-7.2 16-16 16l-32 0 0 48c0 8.8-7.2 16-16 16s-16-7.2-16-16l0-64 0-64z\" fill=\"#0047a7\"\u003e\u003c\/path\u003e\u003c\/svg\u003e\n\u003cdiv\u003e\n\u003cp class=\"DAV-item-title\"\u003eBaader Planetarium SunDancer II H-alpha Filter Manual\u003c\/p\u003e\n\u003c\/div\u003e\n\u003c\/a\u003e\u003c\/li\u003e\n\u003cli class=\"DAV-grid-item\"\u003e\u003ca href=\"https:\/\/cdn.shopify.com\/s\/files\/1\/0753\/5280\/1565\/files\/Baader_Planetarium_SunDancer_II_3x_Telecentric_TZ-3S_Technical_Drawing.pdf\" target=\"_blank\"\u003e\u003csvg class=\"DAV-img-box\" viewbox=\"0 0 512 512\" xmlns=\"http:\/\/www.w3.org\/2000\/svg\"\u003e\u003cpath d=\"M0 64C0 28.7 28.7 0 64 0L224 0l0 128c0 17.7 14.3 32 32 32l128 0 0 144-208 0c-35.3 0-64 28.7-64 64l0 144-48 0c-35.3 0-64-28.7-64-64L0 64zm384 64l-128 0L256 0 384 128zM176 352l32 0c30.9 0 56 25.1 56 56s-25.1 56-56 56l-16 0 0 32c0 8.8-7.2 16-16 16s-16-7.2-16-16l0-48 0-80c0-8.8 7.2-16 16-16zm32 80c13.3 0 24-10.7 24-24s-10.7-24-24-24l-16 0 0 48 16 0zm96-80l32 0c26.5 0 48 21.5 48 48l0 64c0 26.5-21.5 48-48 48l-32 0c-8.8 0-16-7.2-16-16l0-128c0-8.8 7.2-16 16-16zm32 128c8.8 0 16-7.2 16-16l0-64c0-8.8-7.2-16-16-16l-16 0 0 96 16 0zm80-112c0-8.8 7.2-16 16-16l48 0c8.8 0 16 7.2 16 16s-7.2 16-16 16l-32 0 0 32 32 0c8.8 0 16 7.2 16 16s-7.2 16-16 16l-32 0 0 48c0 8.8-7.2 16-16 16s-16-7.2-16-16l0-64 0-64z\" fill=\"#0047a7\"\u003e\u003c\/path\u003e\u003c\/svg\u003e\n\u003cdiv\u003e\n\u003cp class=\"DAV-item-title\"\u003eBaader Planetarium SunDancer II 3x Telecentric TZ-3S Technical Drawing\u003c\/p\u003e\n\u003c\/div\u003e\n\u003c\/a\u003e\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003c\/li\u003e\n\u003cli\u003e\n\u003ca href=\"https:\/\/davidastro.com\/pages\/baader-planetarium-warranty-policy\" rel=\"noopener\" target=\"_blank\"\u003eBaader Planetarium Warranty\u003c\/a\u003e\n\u003c\/li\u003e\n\u003c\/ul\u003e","brand":"Baader Planetarium","offers":[{"title":"Default Title","offer_id":52913278681373,"sku":"BAA-1363070","price":532.0,"currency_code":"CAD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0753\/5280\/1565\/files\/BaaderPlanetarium-TZ-3S-Telecentric-System-T-2-for-SunDancer-II-and-more-1_9dc28c07-1d7d-4a6d-b473-b36a5ffb442c.jpg?v=1789089026","url":"https:\/\/davidastro.com\/fr\/products\/baader-planetarium-tz-3s-telecentric-system-t-2-for-sundancer-ii-and-more","provider":"David Astro","version":"1.0","type":"link"}