{"title":"Baader TZ Telecentric Systems","description":"\u003cp\u003eBaader TZ telecentric systems extend the focal length by 2x, 3x or 4x while producing a parallel light cone. This telecentric beam is what narrowband solar filters such as the Baader SunDancer II need to deliver even contrast, and it also gives uniform magnification for high-resolution lunar and planetary work.\u003c\/p\u003e\u003cp\u003eThe line includes the TZ-2, the TZ-3 Research Grade and the TZ-4, plus TZ-3S and TZ-4S versions with T-2 threads for SunDancer II.\u003c\/p\u003e","products":[{"product_id":"baader-telecentric-system-tz-2-2x","title":"Baader Telecentric System TZ-2 - 2x","description":"\u003c!-- more --\u003e\u003cul\u003e\n\u003cli\u003eTelecentric with 2\" outer diameter and T-2 threads on both sides\u003c\/li\u003e\n\u003cli\u003eAplanatic, with 2x focal length extension to achieve a parallel f\/30 beam in conjunction with ~f\/7,5 optics systems – free of field curvature\u003c\/li\u003e\n\u003cli\u003eDesigned specifically for H-alpha at 656,3 nm, delivering 99% Strehl (99% definition brightness)\u003c\/li\u003e\n\u003c\/ul\u003e\u003ch3\u003eBaader Telecentric Systems for focal length extension\u003c\/h3\u003e\u003ch4\u003efor supplying a parallel optical beam and for providing sufficient backfocus, in conjunction with any SolarSpectrum H-alpha filter\u003c\/h4\u003e\u003cp\u003eTelecentric optics sets are often confused with a barlow lens. Both can be used to increase the focal length. Telecentric assys are designed so that the exit pupil seemingly is positioned at infinity, which means that the center ray from any point in the field appears to come from infinity and is therefore perpendicular to the image plane and parallel to the optic axis. This means that the off axis beam does arrive at the image plane with the same angular geometry as the axial rays. All field elements look as if they where on axis, across the image plane and - unlike to a barlow lens - the edge field rays are not tipped bundles.\u003c\/p\u003e\u003cp\u003eBecause all the principal rays across the image plane are perpendicular to the image plane, the rays at the edge of the field will pass through an etalon just in front of the focal plane with exactly the same geometry as the rays on axis. So in an f\/30 telecentric optical arrangement, the etalon sees the exact same geometry clear across the field, and the spectral bandpass does not shift in wavelength across the entire field of view.\u003c\/p\u003e\u003cp\u003eStarting from an aperture ratio of ~f\/15 (+2x Telecentric), ~f\/10 (+3x Telecentric) or ~f\/7.5 (+4x Telecentric), the Baader TZ-systems will create a parallel beam with ~f\/30 aperture ratio. In the case of largely deviating telescope focal lengths, the clear objective aperture of the telescope should be reduced in diameter to the point that the final resulting f\/ratio is close to f\/30 again (we do offer a suitable iris-diaphragm for this purpose).\u003c\/p\u003e\u003cp\u003eTZ-system working distance to the camera sensor – when measured from their rear lens – range from 200mm for the TZ-2 to 230 mm for the TZ-4 - to 250 mm for the TZ-3. This provides enough room for the H-alpha filter housing and most any accessories, e.g. a Baader 2\" mirror diagonal or any conceivable camera device. All TZ-coatings are matched to the different lens glass-substrates and optimized for maximum throughput at 656 nm.\u003c\/p\u003e\u003cdiv data-custom-tab\u003e\n\u003cp data-custom-tab-title\u003eSpecifications\u003c\/p\u003e\n\u003cdiv\u003e\u003ctable\u003e\u003ctbody\u003e\n\u003ctr\u003e\n\u003cth\u003eMANUFACTURER\u003c\/th\u003e\n\u003ctd\u003eBaader Planetarium\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003cth\u003eSKU (#)\u003c\/th\u003e\n\u003ctd\u003e2459255\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003cth\u003eEAN CODE\u003c\/th\u003e\n\u003ctd\u003e4047825008701\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003cth\u003eWEIGHT (KG)\u003c\/th\u003e\n\u003ctd\u003e0.356\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003cth\u003eFOCAL LENGTH EXTENSION\u003c\/th\u003e\n\u003ctd\u003e2-fach\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003cth\u003eUSAGE\u003c\/th\u003e\n\u003ctd\u003efor H-alpha observation with SolarSpectrum Filters\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003cth\u003eINNER CONNECTION (LENS SIDED)\u003c\/th\u003e\n\u003ctd\u003eThread, T-2 (M42 x 0,75)\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003cth\u003eOUTER CONNECTION (EYEPIECE\/-CAMERA-SIDED)\u003c\/th\u003e\n\u003ctd\u003eThread, T-2 (M42 x 0,75)\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003c\/tbody\u003e\u003c\/table\u003e\u003c\/div\u003e\n\u003c\/div\u003e\u003cdiv class=\"moretab\" data-title=\"Downloads \u0026amp; Support\"\u003e\n\u003cp\u003e\u003ca href=\"https:\/\/cdn.shopify.com\/s\/files\/1\/0753\/5280\/1565\/t\/6\/assets\/description_image_baader_telecentric_systems_tzs_for_h_solar_filters.pdf?v=1684341062?v=1590568855\" target=\"_blank\"\u003eBaader Telecentric Systems (TZS) for H-α solar filters\u003c\/a\u003e\u003c\/p\u003e\n\u003cp\u003e\u003ca href=\"https:\/\/cdn.shopify.com\/s\/files\/1\/0753\/5280\/1565\/t\/6\/assets\/description_image_baader_m68_tele_compendium_telescope_connector_for_solarspectrum_baader_ffc_and_telecentric_systems.pdf?v=1684340407?v=1590568479\" target=\"_blank\"\u003eBaader M68 Tele-Compendium | Telescope-connector for SolarSpectrum, Baader FFC and telecentric systems\u003c\/a\u003e\u003c\/p\u003e\n\u003c\/div\u003e","brand":"Baader Planetarium","offers":[{"title":"Default Title","offer_id":44967382155549,"sku":"BAA-2459255","price":657.0,"currency_code":"CAD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0753\/5280\/1565\/products\/Baader-Telecentric-System-TZ-2-2x-1__36823.1597111120.1280.1280.jpg?v=1684341743"},{"product_id":"baader-telecentric-system-tz-3-3x-research-grade","title":"Baader Telecentric System TZ-3  - 3x Research Grade","description":"\u003cul class=\"DAV-feature-list\"\u003e\n\u003cli\u003e3x Telecentric Focal Extender\u003c\/li\u003e\n\u003cli\u003eEngineered for Narrowband H-alpha Solar Filters\u003c\/li\u003e\n\u003cli\u003eProduces a Parallel (Collimated) Light Path\u003c\/li\u003e\n\u003cli\u003eMaintains Etalon Bandpass Across the Entire Field\u003c\/li\u003e\n\u003cli\u003eResearch Grade Optical Design\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\u003eBaader Telecentric System TZ-3 - 3x Research Grade\u003c\/h2\u003e\n\u003cp\u003eThe Baader Telecentric System TZ-3 is an essential optical component for high-resolution solar imaging, providing a 3x focal length amplification designed to create a perfectly parallel light path. This research-grade system is not a simple Barlow lens; it is an engineered solution to ensure that expensive, sub-angstrom H-alpha etalons deliver their full theoretical contrast and resolution across the entire imaging sensor.\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\u003eA 3x Focal Extender for Optimized Etalon Illumination\u003c\/h3\u003e\n\u003cp\u003eThe primary function of the TZ-3 is to convert your telescope's native focal ratio into the slow, collimated beam required by SolarSpectrum and other high-end H-alpha filters. By increasing the effective focal length by a factor of 3x, a telescope operating around f\/10 is transformed into the target f\/30 system, ensuring every ray of light passes through the delicate etalon perpendicularly. This precise illumination is the only way to prevent bandpass shift and preserve uniform detail from the center of the solar disk to the limb.\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 Telecentric Principle: A Parallel Light Path, Not Just Magnification\u003c\/h3\u003e\n\u003cp\u003eA telecentric system is designed to place its exit pupil at infinity. The result is that principal rays from any point in the field of view strike the image plane parallel to the main optical axis, as if they originated from the center of the field. This is fundamentally different from a Barlow, where off-axis rays are still angled. This parallel light path is the key to the TZ-3's function, guaranteeing that the filter's bandpass remains constant and does not shift toward shorter wavelengths at the edge of the field.\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\u003eA Mandatory Component for Sub-Angstrom Solar Etalons\u003c\/h3\u003e\n\u003cp\u003eFor any H-alpha observation with a filter narrower than 1 Angstrom, a telecentric system is not optional—it is mandatory. Feeding a non-parallel, or conical, light beam into a sub-angstrom etalon destroys its contrast. An etalon rated for 0.5Å performance might deliver only 0.7Å or worse if used with a standard Barlow at the same focal ratio. The Baader TZ-3 is the prerequisite for unlocking the true, high-contrast potential of your specialized solar filter, revealing fine spicules, plage, and filament details that would otherwise be lost to bandpass artifacts.\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\u003eBaader TZ-3 vs. A Standard Barlow Lens: Why It Matters\u003c\/h3\u003e\n\u003cp\u003eWhile both a Barlow and a Telecentric system increase focal length, their impact on a narrowband filter is radically different. A Barlow lens simply makes the light cone narrower; it does not make the rays parallel.\n\u003c\/p\u003e\n\u003cul\u003e\n\u003cli\u003e\n\u003cstrong\u003eBaader TZ-3:\u003c\/strong\u003e Creates a true, parallel optical path. The etalon sees the same perpendicular light rays across the entire field, preserving the specified bandpass and delivering maximum contrast uniformly.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eBarlow Lens:\u003c\/strong\u003e Creates a converging light cone. Off-axis rays still enter the etalon at an angle, causing a spectral shift that degrades contrast and resolution, especially away from the center of the field. Using a Barlow in a serious H-alpha system is a fundamental optical mismatch.\u003c\/li\u003e\n\u003c\/ul\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\"\u003eWhy is the Baader TZ-3 essential for my sub-angstrom H-alpha filter?\u003c\/h3\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion-A\"\u003e\n\u003cp\u003eSub-angstrom H-alpha filters, known as etalons, require a perfectly parallel light path (collimated beam) to function correctly. The \u003cstrong\u003eBaader TZ-3\u003c\/strong\u003e is specifically designed to create this beam. Using a standard Barlow lens, even if it achieves the same f-ratio, will result in a conical light path that degrades the filter's performance, severely reducing contrast and detail.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion\"\u003e\n\u003ch3 class=\"DAV-accordion-Q\"\u003eHow is the Baader TZ-3 different from a standard 3x Barlow lens?\u003c\/h3\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion-A\"\u003e\n\u003cp\u003eA Barlow lens only magnifies the image by making the light cone narrower. A telecentric system, like the \u003cstrong\u003eBaader TZ-3\u003c\/strong\u003e, fundamentally re-engineers the optical path to make the light rays parallel to the central axis. This is a critical distinction for narrowband filters, as angled rays cause the filter's bandpass to shift, smearing out fine solar details.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion\"\u003e\n\u003ch3 class=\"DAV-accordion-Q\"\u003eCan I use the Baader TZ-3 for lunar or planetary imaging?\u003c\/h3\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion-A\"\u003e\n\u003cp\u003eWhile the TZ-3 is optimized for the specific requirements of solar etalons, it can be used as a high-quality 3x focal extender for other targets. However, its primary design goal is to produce a telecentric beam, which is not a requirement for standard planetary imaging where a high-quality Barlow may offer a more compact and cost-effective solution.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion\"\u003e\n\u003ch3 class=\"DAV-accordion-Q\"\u003eWhat happens if I use a Barlow instead of the Baader TZ-3 with my SolarSpectrum filter on my f\/10 SCT?\u003c\/h3\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion-A\"\u003e\n\u003cp\u003eEven if you use a 3x Barlow to achieve f\/30, the light entering your SolarSpectrum filter will still be in a converging cone. This will cause a bandpass shift across the field of view. The center of the sun might look sharp, but the detail and contrast towards the limb will be significantly reduced, and the filter will not perform to its specified sub-angstrom rating.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion\"\u003e\n\u003ch3 class=\"DAV-accordion-Q\"\u003eMy telescope is f\/7. How does the Baader TZ-3 help me for H-alpha?\u003c\/h3\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion-A\"\u003e\n\u003cp\u003eAn f\/7 telescope with the 3x TZ-3 would result in an f\/21 system. This is faster than the ideal f\/30 target for many etalons. To compensate, you would need to use an aperture mask or iris diaphragm on your telescope's objective to reduce its effective aperture, thereby slowing the system down to the required f\/30, ensuring optimal filter performance.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion\"\u003e\n\u003ch3 class=\"DAV-accordion-Q\"\u003eWhy is the Baader TZ-3 recommended over the older TZ-4 for some setups?\u003c\/h3\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion-A\"\u003e\n\u003cp\u003eThe Baader TZ-3 features a more modern optical calculation and better clear aperture matching for many modern filter systems. It is often better to use the TZ-3 and slightly reduce your telescope's main aperture to reach the target f\/30 than to use an older, mismatched 4x system that may introduce vignetting or other optical compromises.\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\u003eFocal Length Multiplier\u003c\/td\u003e\n\u003ctd\u003e3x\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eOptical System\u003c\/td\u003e\n\u003ctd\u003eTelecentric\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003ePrimary Application\u003c\/td\u003e\n\u003ctd\u003eNarrowband H-alpha Solar Filters\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eNet weight (kg)\u003c\/td\u003e\n\u003ctd\u003e0.21\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eUsage\u003c\/td\u003e\n\u003ctd\u003efor H-alpha observation with SolarSpectrum filters\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), 2\"\/SCT Thread (50.8mm)\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eInner Connection (lens 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\u003e2\"\/SCT Thread (50.8mm)\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_Telecentric_Systems_TZS_for_H-alpha_Filters_Product_Information.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 Telecentric Systems TZS for H-alpha Filters Product Information\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":44967382188317,"sku":"BAA-2459257","price":648.0,"currency_code":"CAD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0753\/5280\/1565\/products\/Baader-Telecentric-System-TZ-3-3x-Research-Grade-1__65124.1597111122.1280.1280.jpg?v=1684341500"},{"product_id":"baader-telecentric-system-tz-4-4x","title":"Baader Telecentric System TZ-4 - 4x","description":"\u003cul class=\"DAV-feature-list\"\u003e\n\u003cli\u003e4x Telecentric Focal Extender\u003c\/li\u003e\n\u003cli\u003eEngineered for Narrowband H-alpha Solar Filters\u003c\/li\u003e\n\u003cli\u003eCreates a Parallel f\/30 Light Path\u003c\/li\u003e\n\u003cli\u003eOptimized Coatings for 656nm Wavelength\u003c\/li\u003e\n\u003cli\u003eProvides 230mm of Back Focus for Accessories\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\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\u003eBaader Telecentric System TZ-4 - 4x\u003c\/h2\u003e\n      \u003cp\u003eThe Baader Telecentric System TZ-4 is an essential optical component designed specifically for high-resolution H-alpha solar imaging, delivering a 4x focal length amplification. It transforms a native f\/7.5 telescope into the mandatory f\/30 parallel light path required by sub-Angstrom etalon filters. With coatings optimized for the critical 656nm H-alpha wavelength and a generous 230mm of working distance, the TZ-4 ensures your entire optical train works in perfect harmony for maximum contrast and uniformity.\u003c\/p\u003e\n    \u003c\/div\u003e\n  \u003c\/div\u003e\n\n  \u003cdiv class=\"DAV-bg-light\"\u003e\n    \u003cdiv class=\"DAV-section\"\u003e\n      \u003ch3\u003eTrue Telecentric Design: A Parallel Light Path for \u0026lt;1Å Etalons\u003c\/h3\u003e\n      \u003cp\u003eUnlike a standard Barlow lens that creates a diverging cone of light, a telecentric system produces a beam where the principal light rays remain parallel to the optical axis across the entire field of view. This is absolutely mandatory for narrowband solar filters with a bandpass below 1 Angstrom. A parallel beam ensures that light enters the etalon at the correct angle everywhere on the sensor, preventing bandpass shift that would otherwise degrade contrast and create uneven illumination.\u003c\/p\u003e\n    \u003c\/div\u003e\n  \u003c\/div\u003e\n\n    \u003cdiv class=\"DAV-bg-light\"\u003e\n    \u003cdiv class=\"DAV-section\"\u003e\n      \u003ch3\u003eOptimized for H-alpha: f\/30 Performance at 656nm\u003c\/h3\u003e\n      \u003cp\u003eThe TZ-4 is engineered to convert an f\/7.5 instrument into an f\/30 system, the ideal focal ratio for most high-end solar etalons. All optical surfaces feature multi-layer coatings precisely matched to the glass types used, maximizing light transmission at the 656nm H-alpha line. If your telescope's native focal ratio deviates significantly, the aperture can be stopped down with an optional iris to achieve the target f\/30 ratio, ensuring your filter performs at its theoretical best.\u003c\/p\u003e\n    \u003c\/div\u003e\n  \u003c\/div\u003e\n\n  \u003cdiv class=\"DAV-bg-light\"\u003e\n    \u003cdiv class=\"DAV-section\"\u003e\n      \u003ch3\u003eGenerous 230mm Back Focus: Room for Diagonals and Cameras\u003c\/h3\u003e\n      \u003cp\u003eA key practical advantage of the TZ-4 is the 230mm of back focus available, measured from the rear lens surface to the camera sensor. This substantial distance provides ample room to insert a Solar Spectrum filter housing, a 2\" mirror diagonal for more comfortable viewing angles, and your imaging camera without running out of space. This flexibility allows for robust and stable imaging train configurations that are difficult to achieve with other focal extenders.\u003c\/p\u003e\n    \u003c\/div\u003e\n  \u003c\/div\u003e\n\n  \u003cdiv class=\"DAV-bg-light\"\u003e\n    \u003cdiv class=\"DAV-section\"\u003e\n      \u003ch3\u003eTZ-4 vs. TZ-3: Understanding the Baader Telecentric Lineup\u003c\/h3\u003e\n      \u003cp\u003eThe TZ-4 is a legacy component in Baader's telecentric lineup. For many applications, the newer Baader TZ-3 represents a more modern and optically superior calculation. It is often recommended to start with a TZ-3 and stop down the telescope's aperture to reach the target f\/30, as this can yield higher contrast than using a TZ-4 on a poorly matched system. While a newly calculated, large-aperture TZ-4 is in development, the current model serves specific needs for achieving a 4x amplification factor where required.\u003c\/p\u003e\n    \u003c\/div\u003e\n  \u003c\/div\u003e\n\n\u003c\/div\u003e\n\u003c\/li\u003e\n\n\u003cli\u003e\n  \u003cdiv class=\"DAV-accordion\"\u003e\n    \u003ch3 class=\"DAV-accordion-Q\"\u003eWhy can't I use a 4x Barlow with my Solar Spectrum filter instead of the Baader TZ-4?\u003c\/h3\u003e\n  \u003c\/div\u003e\n  \u003cdiv class=\"DAV-accordion-A\"\u003e\n    \u003cp\u003eA Barlow lens creates a diverging light cone, meaning light rays at the edge of the field strike the filter at a different angle than those in the center. This causes a \u003cstrong\u003ebandpass shift\u003c\/strong\u003e, degrading contrast and detail. The \u003cstrong\u003eBaader TZ-4 creates a parallel light path\u003c\/strong\u003e, ensuring every ray of light enters the etalon at the correct angle, preserving the filter's specified performance across the entire solar disk.\u003c\/p\u003e\n  \u003c\/div\u003e\n  \u003cdiv class=\"DAV-accordion\"\u003e\n    \u003ch3 class=\"DAV-accordion-Q\"\u003eWhat telescope focal ratio works best with the Baader TZ-4 for solar imaging?\u003c\/h3\u003e\n  \u003c\/div\u003e\n  \u003cdiv class=\"DAV-accordion-A\"\u003e\n    \u003cp\u003eThe Baader TZ-4 is designed to work optimally with a telescope that has a native focal ratio of approximately \u003cstrong\u003ef\/7.5\u003c\/strong\u003e. This combination produces the target \u003cstrong\u003ef\/30\u003c\/strong\u003e beam required by many narrowband H-alpha etalons. If your telescope is faster or slower, you may need to use an iris diaphragm to stop down the aperture to achieve this ideal f\/30 ratio.\u003c\/p\u003e\n  \u003c\/div\u003e\n  \u003cdiv class=\"DAV-accordion\"\u003e\n    \u003ch3 class=\"DAV-accordion-Q\"\u003eHow much space does the TZ-4 leave for my H-alpha etalon and camera?\u003c\/h3\u003e\n  \u003c\/div\u003e\n  \u003cdiv class=\"DAV-accordion-A\"\u003e\n    \u003cp\u003eThe Baader TZ-4 provides a generous working distance of \u003cstrong\u003e230mm\u003c\/strong\u003e from its rearmost lens to the focal plane. This is typically sufficient space to accommodate the etalon filter housing, a 2\" diagonal, and your imaging camera without issue.\u003c\/p\u003e\n  \u003c\/div\u003e\n    \u003cdiv class=\"DAV-accordion\"\u003e\n    \u003ch3 class=\"DAV-accordion-Q\"\u003eMy telescope isn't f\/7.5. Can I still use the TZ-4 to get to f\/30 for solar imaging?\u003c\/h3\u003e\n  \u003c\/div\u003e\n  \u003cdiv class=\"DAV-accordion-A\"\u003e\n    \u003cp\u003eYes. While the TZ-4 is optimized for a starting f\/7.5 system, you can use it with other telescopes by adjusting the effective aperture. For a faster telescope (e.g., f\/6), you would need to use an \u003cstrong\u003eaperture stop or iris diaphragm\u003c\/strong\u003e in front of the objective lens to reduce the incoming light, effectively changing the focal ratio to the f\/7.5 needed to achieve a final f\/30 output.\u003c\/p\u003e\n  \u003c\/div\u003e\n  \u003cdiv class=\"DAV-accordion\"\u003e\n    \u003ch3 class=\"DAV-accordion-Q\"\u003eThe documentation mentions the TZ-3 is a better design. Why would I buy the Baader TZ-4?\u003c\/h3\u003e\n  \u003c\/div\u003e\n  \u003cdiv class=\"DAV-accordion-A\"\u003e\n    \u003cp\u003eThe Baader TZ-4 is an older, established design that provides a specific \u003cstrong\u003e4x amplification factor\u003c\/strong\u003e. You would choose the TZ-4 if this exact magnification is required to bring your specific telescope to the necessary f\/30 focal ratio. For new systems, Baader often recommends the newer TZ-3 due to its more advanced optical calculation, suggesting it may provide better contrast even if it requires stopping down the telescope's aperture.\u003c\/p\u003e\n  \u003c\/div\u003e\n  \u003cdiv class=\"DAV-accordion\"\u003e\n    \u003ch3 class=\"DAV-accordion-Q\"\u003eWhat does \"telecentric\" actually mean for my solar images from the TZ-4?\u003c\/h3\u003e\n  \u003c\/div\u003e\n  \u003cdiv class=\"DAV-accordion-A\"\u003e\n    \u003cp\u003eFor your images, \"telecentric\" means \u003cstrong\u003euniformity and maximum contrast\u003c\/strong\u003e. Because the light passing through your etalon is perfectly parallel everywhere, the filter's narrow bandpass is maintained across the entire sensor. This prevents bright or dark blotches (sweet-banding) and ensures that fine details like spicules and filaments are visible with the highest possible contrast from edge to edge.\u003c\/p\u003e\n  \u003c\/div\u003e\n\u003c\/li\u003e\n\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\u003e0.31\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eFocal length extension\u003c\/td\u003e\n\u003ctd\u003e4-fach\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\u003eInner Connection (lens 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 2\" (50.8mm)\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003c\/tbody\u003e\n\u003c\/table\u003e\n\u003c\/li\u003e\n\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_Telecentric_System_TZ-2_Working_Distance_Notes.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 Telecentric System TZ-2 Working Distance Notes\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_Telecentric_Systems_TZS_for_H-alpha_Filters_Product_Information.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 Telecentric Systems TZS for H-alpha Filters Product Information\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_M68_Tele-Compendium_Telescope_Connector_Guide.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 M68 Tele-Compendium Telescope Connector Guide\u003c\/p\u003e\n\u003c\/div\u003e\n\u003c\/a\u003e\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003c\/li\u003e\n\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":44967382253853,"sku":"BAA-2459256","price":657.0,"currency_code":"CAD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0753\/5280\/1565\/products\/Baader-Telecentric-System-TZ-4-4x-1__98750.1597111122.1280.1280.jpg?v=1684341504"},{"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"},{"product_id":"baader-planetarium-tz-4s-telecentric-system-t-2-for-sundancer-ii-and-more","title":"Baader Planetarium TZ-4S Telecentric System T-2 for SunDancer II and more","description":"\u003cul class=\"DAV-feature-list\"\u003e\n\u003cli\u003eCreates a parallel beam of light required for H-alpha solar filters\u003c\/li\u003e\n\u003cli\u003eHigher magnification factor for using solar filters on faster telescopes\u003c\/li\u003e\n\u003cli\u003eMaintains a constant magnification factor regardless of working distance\u003c\/li\u003e\n\u003cli\u003eConnects via a standard T-2 thread and a dual 1.25\"\/2\" nosepiece\u003c\/li\u003e\n\u003cli\u003ePreserves the native eye relief of visual eyepieces\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\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-4S Telecentric System T-2 for SunDancer II and more\u003c\/h2\u003e\n      \u003cp\u003eThe Baader TZ-4S Telecentric System is engineered to produce a perfectly parallel beam of light, an essential requirement for the etalon in any high-resolution H-alpha solar filter like the SunDancer II. It connects to your camera or eyepiece holder via a rigid T-2 thread and fits any telescope focuser with its dual 1.25\" and 2\" nosepiece.\u003c\/p\u003e\n    \u003c\/div\u003e\n  \u003c\/div\u003e\n\n  \u003cdiv class=\"DAV-bg-light\"\u003e\n    \u003cdiv class=\"DAV-section\"\u003e\n      \u003ch3\u003eA Parallel Light Path for Uncompromised H-alpha Contrast\u003c\/h3\u003e\n      \u003cp\u003eFor H-alpha filters with a narrow half-bandwidth, a telecentric optical system is mandatory. Standard Barlow lenses or focal extenders create a converging light cone, which degrades the filter's performance and significantly reduces contrast. The TZ-4S ensures the light rays are perfectly parallel across the entire field before they enter the etalon, allowing the filter to operate at its maximum theoretical contrast and reveal the finest solar details.\u003c\/p\u003e\n    \u003c\/div\u003e\n  \u003c\/div\u003e\n\n  \u003cdiv class=\"DAV-bg-light\"\u003e\n    \u003cdiv class=\"DAV-section\"\u003e\n      \u003ch3\u003eHigh-Magnification Viewing Without Barlow Lens Drawbacks\u003c\/h3\u003e\n      \u003cp\u003eBeyond solar applications, the TZ-4S serves as a superior alternative to a Barlow lens for high-magnification visual observation of the planets. Unlike a Barlow, whose magnification changes with distance, a telecentric system maintains its specified magnification factor and optical quality regardless of the spacing to the eyepiece or camera. This design also preserves the original eye relief of your eyepiece, ensuring comfortable views even at high power.\u003c\/p\u003e\n    \u003c\/div\u003e\n  \u003c\/div\u003e\n\n  \u003cdiv class=\"DAV-bg-light\"\u003e\n    \u003cdiv class=\"DAV-section\"\u003e\n      \u003ch3\u003eAdapting the SunDancer II for Shorter Focal Ratio Telescopes\u003c\/h3\u003e\n      \u003cp\u003eThe TZ-4S is the key to using the Baader SunDancer II H-alpha filter on telescopes with shorter native focal ratios, such as f\/7 or f\/8 apochromatic refractors. It provides the necessary magnification to convert the telescope's light cone into the slow, parallel beam required by the SunDancer's etalon. This allows owners of faster instruments to achieve the same stunning solar views as those with longer-focal-length telescopes.\u003c\/p\u003e\n      \u003cul\u003e\n        \u003cli\u003e\n\u003cstrong\u003eCritical User Note:\u003c\/strong\u003e To use the TZ-4S with a SunDancer II filter, you must transfer the 2nm blocking filter from the original 3x telecentric (TZ-3S) supplied with your SunDancer. The blocking filter is not included with the TZ-4S and is not available for separate purchase.\u003c\/li\u003e\n      \u003c\/ul\u003e\n    \u003c\/div\u003e\n  \u003c\/div\u003e\n\n    \u003cdiv class=\"DAV-bg-light\"\u003e\n    \u003cdiv class=\"DAV-section\"\u003e\n      \u003ch3\u003eSecure Connections with a 1.25\"\/2\" Nosepiece and T-2 Thread\u003c\/h3\u003e\n      \u003cp\u003eThe TZ-4S is built for a secure, tilt-proof fit in any imaging train. The telescope side features a dual-format nosepiece that fits both 1.25\" and 2\" focusers, machined with safety kerfs for a secure grip without marring the barrel. The camera side features a standard T-2 (M42x0.75) male thread, providing a rigid, direct connection to cameras, filter wheels, or T-2 eyepiece clamps, eliminating the potential for flexure that can plague slip-fit adapters.\u003c\/p\u003e\n    \u003c\/div\u003e\n  \u003c\/div\u003e\n\n  \u003cdiv class=\"DAV-bg-light\"\u003e\n    \u003cdiv class=\"DAV-section\"\u003e\n      \u003ch3\u003eTZ-4S vs. TZ-3S: Choosing the Right Telecentric Magnification\u003c\/h3\u003e\n      \u003cp\u003eThe primary difference between the TZ-4S and the TZ-3S included with the SunDancer II filter lies in their intended telescope pairing. Each is designed to produce the optimal final focal ratio for the H-alpha etalon.\u003c\/p\u003e\n      \u003cul\u003e\n        \u003cli\u003e\n\u003cstrong\u003eBaader TZ-3S (Standard):\u003c\/strong\u003e This telecentric is optimized for telescopes with longer native focal ratios, such as f\/10 Schmidt-Cassegrains. It provides the correct magnification to condition the beam for the SunDancer II etalon.\u003c\/li\u003e\n        \u003cli\u003e\n\u003cstrong\u003eBaader TZ-4S (This Product):\u003c\/strong\u003e With its higher magnification, the TZ-4S is designed for telescopes with faster native focal ratios, such as f\/7.5 refractors. It allows these instruments to achieve the same ideal parallel beam, making it the essential upgrade for wide-field telescope owners wanting to perform high-resolution solar imaging.\u003c\/li\u003e\n      \u003c\/ul\u003e\n    \u003c\/div\u003e\n  \u003c\/div\u003e\n\n\u003c\/div\u003e\n\u003c\/li\u003e\n\n\u003cli\u003e\n  \u003cdiv class=\"DAV-accordion\"\u003e\n    \u003ch3 class=\"DAV-accordion-Q\"\u003eWhy is the Baader TZ-4S Telecentric System necessary for H-alpha solar filters?\u003c\/h3\u003e\n  \u003c\/div\u003e\n  \u003cdiv class=\"DAV-accordion-A\"\u003e\n    \u003cp\u003eNarrow-band H-alpha filters, like the Baader SunDancer II, contain an etalon that only performs correctly when fed a \u003cstrong\u003eperfectly parallel beam of light\u003c\/strong\u003e. A standard Barlow lens or the telescope's native focal ratio creates a converging cone of light, which significantly degrades the filter's contrast. The TZ-4S is an optical conditioner that creates this necessary parallel beam, unlocking the filter's full performance.\u003c\/p\u003e\n  \u003c\/div\u003e\n  \u003cdiv class=\"DAV-accordion\"\u003e\n    \u003ch3 class=\"DAV-accordion-Q\"\u003eHow is the TZ-4S different from a standard Barlow lens for viewing Jupiter?\u003c\/h3\u003e\n  \u003c\/div\u003e\n  \u003cdiv class=\"DAV-accordion-A\"\u003e\n    \u003cp\u003eThe TZ-4S offers two main advantages for planetary viewing. First, its magnification factor is \u003cstrong\u003econstant and independent of distance\u003c\/strong\u003e, unlike a Barlow which changes magnification as you move the eyepiece. Second, the TZ-4S \u003cstrong\u003epreserves the eyepiece's native eye relief\u003c\/strong\u003e, making high-power viewing much more comfortable, especially for eyeglass wearers.\u003c\/p\u003e\n  \u003c\/div\u003e\n  \u003cdiv class=\"DAV-accordion\"\u003e\n    \u003ch3 class=\"DAV-accordion-Q\"\u003eCan I use the TZ-4S with my SunDancer II H-alpha filter?\u003c\/h3\u003e\n  \u003c\/div\u003e\n  \u003cdiv class=\"DAV-accordion-A\"\u003e\n    \u003cp\u003eYes, but with a critical requirement. You \u003cstrong\u003emust carefully remove the 2nm H-alpha blocking filter\u003c\/strong\u003e from the front of the TZ-3S telecentric that came with your SunDancer II and install it into the TZ-4S. The TZ-4S does not include this filter, and it cannot be purchased separately. This component is essential for the safe and correct operation of the H-alpha system.\u003c\/p\u003e\n  \u003c\/div\u003e\n  \u003cdiv class=\"DAV-accordion\"\u003e\n    \u003ch3 class=\"DAV-accordion-Q\"\u003eWhat kind of telescope is the TZ-4S designed for when used with the SunDancer II?\u003c\/h3\u003e\n  \u003c\/div\u003e\n  \u003cdiv class=\"DAV-accordion-A\"\u003e\n    \u003cp\u003eThe TZ-4S is designed for telescopes with \u003cstrong\u003eshorter native focal ratios, typically in the f\/7 to f\/8 range\u003c\/strong\u003e, such as apochromatic refractors. The standard TZ-3S is better suited for longer focal ratio instruments like f\/10 Schmidt-Cassegrains. The TZ-4S provides the higher magnification needed for faster scopes to achieve the ideal slow focal ratio for the etalon.\u003c\/p\u003e\n  \u003c\/div\u003e\n    \u003cdiv class=\"DAV-accordion\"\u003e\n    \u003ch3 class=\"DAV-accordion-Q\"\u003eWhat are the connection options on the TZ-4S Telecentric System?\u003c\/h3\u003e\n  \u003c\/div\u003e\n  \u003cdiv class=\"DAV-accordion-A\"\u003e\n    \u003cp\u003eThe TZ-4S offers flexible and secure connections:\u003c\/p\u003e\n    \u003cul\u003e\n      \u003cli\u003e\n\u003cstrong\u003eTelescope Side:\u003c\/strong\u003e A dual-purpose nosepiece that fits into both \u003cstrong\u003e1.25\" and 2\" focusers\u003c\/strong\u003e.\u003c\/li\u003e\n      \u003cli\u003e\n\u003cstrong\u003eCamera\/Eyepiece Side:\u003c\/strong\u003e A standard male \u003cstrong\u003eT-2 (M42x0.75) thread\u003c\/strong\u003e for a rigid, threaded connection to your camera or other T-2 accessories.\u003c\/li\u003e\n    \u003c\/ul\u003e\n  \u003c\/div\u003e\n  \u003cdiv class=\"DAV-accordion\"\u003e\n    \u003ch3 class=\"DAV-accordion-Q\"\u003eWill the TZ-4S change the eye relief of my eyepieces?\u003c\/h3\u003e\n  \u003c\/div\u003e\n  \u003cdiv class=\"DAV-accordion-A\"\u003e\n    \u003cp\u003eNo. A key benefit of the telecentric design is that it \u003cstrong\u003epreserves the original eye relief\u003c\/strong\u003e of any eyepiece you use with it. This is a significant comfort advantage over some other magnification methods, especially during long planetary observing sessions.\u003c\/p\u003e\n  \u003c\/div\u003e\n\u003c\/li\u003e\n\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\u003e0.25\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eInner Diameter \/ Clear Aperture (mm)\u003c\/td\u003e\n\u003ctd\u003e36 mm\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eUsage\u003c\/td\u003e\n\u003ctd\u003efor H-alpha observation with SolarSpectrum filters\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eFocal length extension\u003c\/td\u003e\n\u003ctd\u003e4x\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\u003e36 mm\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003c\/tbody\u003e\n\u003c\/table\u003e\n\u003c\/li\u003e\n\n\u003cli\u003e\n  \u003cul class=\"DAV-grid\"\u003e\n  \u003c\/ul\u003e\n\u003c\/li\u003e\n\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_Blocking_Filter_TZ-3S_to_TZ-4S_Guide.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 Blocking Filter TZ-3S to TZ-4S Guide\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_Telecentric_System_TZ-4S_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 Telecentric System TZ-4S 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\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":52913280319773,"sku":"BAA-1363080","price":561.0,"currency_code":"CAD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0753\/5280\/1565\/files\/BaaderPlanetarium-TZ-4S-Telecentric-System-T-2-for-SunDancer-II-and-more-1_13355d0b-dfeb-4b78-9327-55b02e730c7b.jpg?v=1789089040"}],"url":"https:\/\/davidastro.com\/en-us\/collections\/baader-tz-telecentric-systems.oembed","provider":"David Astro","version":"1.0","type":"link"}