{"product_id":"antlia-lrgb-dark-series-filter-set","title":"Antlia LRGB Dark Series Filter Set","description":"\u003cul class=\"DAV-feature-list\"\u003e\n\u003cli\u003eComplete LRGB (Luminance, Red, Green, Blue) Filter Set\u003c\/li\u003e\n\u003cli\u003eHigh Peak Transmission: ≥97% for L, R, G and ≥95% for B channels\u003c\/li\u003e\n\u003cli\u003eDeep Out-of-Band Blocking at OD4.5 (0.005%)\u003c\/li\u003e\n\u003cli\u003eThermally Stable Quartz Glass Substrate with Double-Sided Fine Polishing\u003c\/li\u003e\n\u003cli\u003eIdeally Paired with Antlia SHO 2.5nm Ultra Filters for Parfocality\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\u003eAntlia LRGB Dark Series Filter Set\u003c\/h2\u003e\n\u003cp\u003eThe Antlia LRGB Dark Series Filter Set is engineered for high-contrast deep-sky imaging, built on a thermally stable quartz glass substrate. With peak transmission of 97% or more for the L, R, and G channels and 95% or more for Blue, the set covers the visible spectrum (L: 400-710nm on Antlia's 50mm specification). Out-of-band blocking at OD4.5 (0.005%) blocks interference from other wavelengths and minimizes halos around bright stars, for high signal-to-noise ratio and 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\u003eHigh-Transmission LRGB Filters: 95% to 97% Peak Throughput\u003c\/h3\u003e\n\u003cp\u003eThe Luminance, Red, and Green filters achieve a peak transmission of 97% or greater, while the Blue filter reaches 95% or greater. Antlia says this ensures that there is almost no loss in image signal, maximizing 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\u003eOD4.5 Blocking for High-Contrast \"Dark Series\" Imaging\u003c\/h3\u003e\n\u003cp\u003eThe Dark Series filters have out-of-band blocking rated at an optical density (OD) of 4.5 or better, which means no more than 0.005% of light from other wavelengths passes through. Antlia describes an exceptionally high cut-off rate that blocks interference from other wavelengths and minimizes halos around bright stars.\u003c\/p\u003e\n\u003cul\u003e\n\u003cli\u003e\n\u003cstrong\u003eDeep Blocking:\u003c\/strong\u003e OD4.5 blocking reduces interference from wavelengths outside each passband.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eEdge-Blackened Design:\u003c\/strong\u003e All Antlia filters are coated to the edge of the substrate, and unmounted sizes are edge blackened to eliminate internal reflections from stray light.\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003c\/div\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-bg-light\"\u003e\n\u003cdiv class=\"DAV-section\"\u003e\n\u003ch3\u003eQuartz Glass Substrate for Thermal Stability\u003c\/h3\u003e\n\u003cp\u003eThe Antlia LRGB Dark Series uses a quartz substrate with an ultra-low thermal expansion coefficient (3mm +\/-0.05mm thick on the 50mm size). Antlia says the deformation of star points induced by environmental temperature variations can be effectively minimized. The filters have an identical thickness to existing standards and double-sided fine polishing, with utmost care for parfocality.\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\u003eIdeally Paired with Antlia 2.5nm Ultra Narrowband Filters\u003c\/h3\u003e\n\u003cp\u003eAntlia says the LRGB Dark Series filters are ideally paired with its SHO 2.5nm Ultra narrowband filters, as both use the same quartz substrate and refractive index, ensuring superior parfocality. Check focus when switching between LRGB and narrowband exposures.\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 are the key features of the Antlia LRGB Dark Series?\u003c\/h3\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion-A\"\u003e\n\u003cp\u003eAntlia highlights the \u003cstrong\u003eOD4.5 out-of-band blocking\u003c\/strong\u003e and the \u003cstrong\u003equartz glass substrate\u003c\/strong\u003e. The blocking (passing just 0.005% of light from other wavelengths) blocks interference and minimizes halos around bright stars, while the quartz glass gives excellent durability and thermal stability, so star-point deformation from temperature changes is minimized.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion\"\u003e\n\u003ch3 class=\"DAV-accordion-Q\"\u003eAre the Antlia Dark Series filters parfocal?\u003c\/h3\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion-A\"\u003e\n\u003cp\u003eAntlia says the filters have an identical thickness to existing standards and double-sided fine polishing, with utmost care for parfocality. They are ideally paired with the \u003cstrong\u003eAntlia SHO 2.5nm Ultra narrowband filters\u003c\/strong\u003e, as both use the same quartz substrate and refractive index, ensuring superior parfocality. A quick focus check after a filter change is still good practice.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion\"\u003e\n\u003ch3 class=\"DAV-accordion-Q\"\u003eWhy are these Antlia filters made from quartz glass instead of standard optical glass?\u003c\/h3\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion-A\"\u003e\n\u003cp\u003eQuartz glass has an extremely low coefficient of thermal expansion. Antlia says this gives exceptional thermal and mechanical properties, so the \u003cstrong\u003edeformation of star points\u003c\/strong\u003e induced by environmental temperature variations can be effectively minimized. Quartz also gives better fracture and scratch resistance and improved coating resilience to cleaning.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion\"\u003e\n\u003ch3 class=\"DAV-accordion-Q\"\u003eCan I use the Antlia LRGB Dark filters for visual observing?\u003c\/h3\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion-A\"\u003e\n\u003cp\u003eNo. Antlia lists night visual observation as not recommended for these filters. They are designed for deep-sky imaging.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion\"\u003e\n\u003ch3 class=\"DAV-accordion-Q\"\u003eHow will the OD4.5 blocking on the Antlia LRGB Dark filters help when imaging a bright star cluster like the Pleiades (M45)?\u003c\/h3\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion-A\"\u003e\n\u003cp\u003eAntlia designs the \u003cstrong\u003eOD4.5 blocking\u003c\/strong\u003e to block interference from other wavelengths and minimize halos around bright stars, which helps with bright-star targets like the Pleiades (M45). Edge coating, and edge blackening on unmounted sizes, also eliminate internal reflections from stray light.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion\"\u003e\n\u003ch3 class=\"DAV-accordion-Q\"\u003eWill the Antlia LRGB Dark Series filters work well for imaging galaxies like Andromeda (M31) from my backyard?\u003c\/h3\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion-A\"\u003e\n\u003cp\u003eYes, galaxies like the Andromeda Galaxy (M31) are broadband targets suited to LRGB imaging. These are not light pollution filters; Antlia designs the Dark Series for high signal-to-noise ratio and contrast, with high transmission and \u003cstrong\u003eOD4.5 blocking\u003c\/strong\u003e of other wavelengths.\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\u003eFilter Type\u003c\/td\u003e\n\u003ctd\u003eLRGB Dark series set\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eFilters in Set\u003c\/td\u003e\n\u003ctd\u003eL (UV\/IR cut), R, G, B\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eSubstrate\u003c\/td\u003e\n\u003ctd\u003eQuartz glass, double-sided fine polishing\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eFilter Thickness\u003c\/td\u003e\n\u003ctd\u003e3mm +\/-0.05mm (50mm size; not stated for 36mm and 2\")\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003ePeak Transmission\u003c\/td\u003e\n\u003ctd\u003eL, R, G ≥97%; B ≥95%\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eLuminance (L) Bandpass\u003c\/td\u003e\n\u003ctd\u003e400nm - 710nm (+\/-10nm, Antlia 50mm page)\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eRed (R) Bandpass\u003c\/td\u003e\n\u003ctd\u003e595nm - 705nm (+\/-10nm, Antlia 50mm page)\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eGreen (G) Bandpass\u003c\/td\u003e\n\u003ctd\u003e495nm - 605nm (+\/-10nm, Antlia 50mm page)\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eBlue (B) Bandpass\u003c\/td\u003e\n\u003ctd\u003e410nm - 505nm (+\/-10nm, Antlia 50mm page)\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eOut-of-Band Blocking\u003c\/td\u003e\n\u003ctd\u003eOD4.5 (0.005%)\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eParfocality\u003c\/td\u003e\n\u003ctd\u003eIdeally paired with Antlia SHO 2.5nm Ultra filters (same quartz substrate and refractive index)\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eEdge Treatment\u003c\/td\u003e\n\u003ctd\u003eCoated to the edge; unmounted sizes are edge blackened\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eFilter Ring (2\" Mounted)\u003c\/td\u003e\n\u003ctd\u003e2\" (M48x0.75), ultra-thin black anodized cell, laser engraved\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eAvailable Sizes\u003c\/td\u003e\n\u003ctd\u003e36mm Round Unmounted, 2\" Mounted, 50mm Round Unmounted\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eNot Recommended For\u003c\/td\u003e\n\u003ctd\u003eSolar imaging, night visual observation\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\u003cli class=\"DAV-grid-item\"\u003e\n\u003cdiv\u003e\n\u003cp class=\"DAV-item-title\"\u003eLuminance (L) Filter\u003c\/p\u003e\n\u003cp class=\"DAV-item-subtitle\"\u003e× 1\u003c\/p\u003e\n\u003c\/div\u003e\n\u003c\/li\u003e\n\u003cli class=\"DAV-grid-item\"\u003e\n\u003cdiv\u003e\n\u003cp class=\"DAV-item-title\"\u003eRed (R) Filter\u003c\/p\u003e\n\u003cp class=\"DAV-item-subtitle\"\u003e× 1\u003c\/p\u003e\n\u003c\/div\u003e\n\u003c\/li\u003e\n\u003cli class=\"DAV-grid-item\"\u003e\n\u003cdiv\u003e\n\u003cp class=\"DAV-item-title\"\u003eGreen (G) Filter\u003c\/p\u003e\n\u003cp class=\"DAV-item-subtitle\"\u003e× 1\u003c\/p\u003e\n\u003c\/div\u003e\n\u003c\/li\u003e\n\u003cli class=\"DAV-grid-item\"\u003e\n\u003cdiv\u003e\n\u003cp class=\"DAV-item-title\"\u003eBlue (B) Filter\u003c\/p\u003e\n\u003cp class=\"DAV-item-subtitle\"\u003e× 1\u003c\/p\u003e\n\u003c\/div\u003e\n\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003c\/li\u003e\n\u003cli\u003e\nAntlia 3-Year Warranty Against Delamination\n\u003c\/li\u003e\n\u003c\/ul\u003e","brand":"Antlia","offers":[{"title":"36mm Round Unmounted","offer_id":51932624814365,"sku":"ANT-LRGB-DARK-RD36","price":450.0,"currency_code":"USD","in_stock":true},{"title":"2\" Mounted","offer_id":51932624847133,"sku":"ANT-LRGB-DARK-2","price":600.0,"currency_code":"USD","in_stock":true},{"title":"50mm Round Unmounted","offer_id":51932624879901,"sku":"ANT-LRGB-DARK-RD50","price":750.0,"currency_code":"USD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0753\/5280\/1565\/files\/antlia-src-o3LGTzwEwoAY4oAY_1726ab03-742f-4215-a6fc-c75274fd206e.jpg?v=1792549997","url":"https:\/\/davidastro.com\/fr-int\/products\/antlia-lrgb-dark-series-filter-set","provider":"David Astro","version":"1.0","type":"link"}