{"product_id":"antlia-photometrics-sloan-griz-4pcs-filter-set","title":"Antlia Photometrics Sloan griz (4pcs) Filter Set","description":"\u003cul class=\"DAV-feature-list\"\u003e\n\u003cli\u003eIncludes 4 Sloan Digital Sky Survey (SDSS) photometric filters: g', r', i', z'\u003c\/li\u003e\n\u003cli\u003ePeak transmission of 98% for r', i', z' filters and 95% for the g' filter\u003c\/li\u003e\n\u003cli\u003eBlocking of OD5 or greater (≥OD5)\u003c\/li\u003e\n\u003cli\u003e3mm +\/-0.05mm thickness, identical to existing standards, with care for parfocality\u003c\/li\u003e\n\u003cli\u003eSuitable from f\/15 to f\/1.8\u003c\/li\u003e\n\u003cli\u003e50mm round unmounted format\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 Photometrics Sloan griz (4pcs) Filter Set - 50mm Unmounted\u003c\/h2\u003e\n\u003cp\u003eThe Antlia Photometrics Sloan griz Filter Set follows the Sloan Digital Sky Survey (SDSS) photometric system, the most common filter set used by observatories today. Its four filters cover 400nm to the sensitivity limit of silicon CCD cameras near 1100nm. Peak transmission is 98% (95% for g') with blocking of OD5 or greater. The filters have a 1\/4-wave propagated wavefront prior to coating and a 3mm thickness identical to existing standards, and the set is suitable from f\/15 to f\/1.8.\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\u003eProfessional g'r'i'z' Bandpasses from 400nm to \u0026gt;812nm\u003c\/h3\u003e\n\u003cp\u003eThis set is built around the Sloan Digital Sky Survey (SDSS) photometric system, the most common filter set used by observatories today. The four included filters define specific spectral windows: the g' filter covers 400-550nm, the r' filter 555-705nm, the i' filter 688-850nm, and the z' filter captures wavelengths longer than 812nm. Antlia states that these wider transmission windows allow fainter objects to be measured in a shorter time, which suits photometry work such as variable star and exoplanet transit measurements.\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\u003e1\/4-Wave Substrates with OD5 Blocking\u003c\/h3\u003e\n\u003cp\u003eAntlia builds these filters on double-sided polished substrates with a 1\/4-wave propagated wavefront prior to coating. Each filter is coated individually, not cut out of a larger coating plate, using Ion Gun Assisted Deposition, which Antlia states makes them consistent, durable and accurate. Blocking is OD5 or greater, and Antlia states this minimizes the already small leakage and creates superior 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\u003eSuitable from f\/15 to f\/1.8, with 3mm Thickness\u003c\/h3\u003e\n\u003cp\u003eAntlia states that the Sloan griz' filter set is suitable from f\/15 to f\/1.8. The filters are 3mm +\/-0.05mm thick, identical to existing standards, made with utmost care for parfocality.\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 primary application for the Antlia Photometric Sloan griz filter set?\u003c\/h3\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion-A\"\u003e\n\u003cp\u003eThis filter set is designed for \u003cstrong\u003escientific photometry\u003c\/strong\u003e, the precise measurement of the brightness of celestial objects. It is used for research applications such as monitoring variable stars, measuring the light curves of supernovae and exoplanet transits, and determining the color indices of stars and galaxies, following the standards of the Sloan Digital Sky Survey (SDSS).\u003c\/p\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion\"\u003e\n\u003ch3 class=\"DAV-accordion-Q\"\u003eWhy is the u' filter not included in this Antlia Sloan set?\u003c\/h3\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion-A\"\u003e\n\u003cp\u003eAntlia does not produce the u' (ultraviolet, 300-400nm) filter because of the mediocre quantum efficiency of cameras in the ultraviolet range.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion\"\u003e\n\u003ch3 class=\"DAV-accordion-Q\"\u003eHow does OD5 blocking on the Antlia Sloan filters improve my data?\u003c\/h3\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion-A\"\u003e\n\u003cp\u003e\u003cstrong\u003eOD5 blocking\u003c\/strong\u003e means the filter attenuates out-of-band light by a factor of 100,000 (10^5). Antlia states that this blocking minimizes the already small leakage and creates superior contrast.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion\"\u003e\n\u003ch3 class=\"DAV-accordion-Q\"\u003eCan I use the Antlia Sloan griz set with fast optics?\u003c\/h3\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion-A\"\u003e\n\u003cp\u003eYes. Antlia states that the set is suitable from \u003cstrong\u003ef\/15 to f\/1.8\u003c\/strong\u003e.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion\"\u003e\n\u003ch3 class=\"DAV-accordion-Q\"\u003eAre the Antlia Sloan filters made for parfocality?\u003c\/h3\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion-A\"\u003e\n\u003cp\u003eThe Antlia Sloan filters are \u003cstrong\u003e3mm +\/-0.05mm\u003c\/strong\u003e thick. Antlia states the thickness is identical to existing standards, with utmost care for parfocality.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion\"\u003e\n\u003ch3 class=\"DAV-accordion-Q\"\u003eWhat kind of astronomical targets are best suited for the Antlia Sloan griz set?\u003c\/h3\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion-A\"\u003e\n\u003cp\u003eThis set is ideal for any target where you need to measure brightness changes or color information. Examples include:\u003c\/p\u003e\n\u003cul\u003e\n\u003cli\u003e\n\u003cstrong\u003eVariable Stars:\u003c\/strong\u003e Tracking the pulsation periods of stars like Cepheids or RR Lyrae.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eSupernovae:\u003c\/strong\u003e Measuring the brightening and fading of exploding stars in distant galaxies.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eExoplanets:\u003c\/strong\u003e Detecting the slight dip in a star's brightness as a planet passes in front of it.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eAsteroids:\u003c\/strong\u003e Determining rotation periods from brightness variations.\u003c\/li\u003e\n\u003c\/ul\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\u003ePhotometric Sloan (SDSS) filter set, 4 filters\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eAvailable Sizes\u003c\/td\u003e\n\u003ctd\u003e50mm Round Unmounted\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eg' Filter Bandpass\u003c\/td\u003e\n\u003ctd\u003e400-550nm\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eg' Filter Peak Transmission\u003c\/td\u003e\n\u003ctd\u003e95%\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003er' Filter Bandpass\u003c\/td\u003e\n\u003ctd\u003e555-705nm\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003er' Filter Peak Transmission\u003c\/td\u003e\n\u003ctd\u003e98%\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003ei' Filter Bandpass\u003c\/td\u003e\n\u003ctd\u003e688-850nm\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003ei' Filter Peak Transmission\u003c\/td\u003e\n\u003ctd\u003e98%\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003ez' Filter Bandpass\u003c\/td\u003e\n\u003ctd\u003e\u0026gt;812nm\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003ez' Filter Peak Transmission\u003c\/td\u003e\n\u003ctd\u003e98%\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eOut-of-Band Blocking\u003c\/td\u003e\n\u003ctd\u003e\u0026gt;=OD5\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eFilter Thickness (50mm)\u003c\/td\u003e\n\u003ctd\u003e3mm +\/-0.05mm\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eSubstrate Wavefront\u003c\/td\u003e\n\u003ctd\u003e1\/4-wave propagated wavefront prior to coating\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eCoating Method\u003c\/td\u003e\n\u003ctd\u003eIon Gun Assisted Deposition, individually coated\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eRecommended f-ratio\u003c\/td\u003e\n\u003ctd\u003ef\/15 to f\/1.8\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eParfocality\u003c\/td\u003e\n\u003ctd\u003eYes, identical thickness to existing standards\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eExcluded Filter\u003c\/td\u003e\n\u003ctd\u003eu' (300-400nm) filter not produced\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\"\u003eg' Sloan Filter (50mm Unmounted)\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\"\u003er' Sloan Filter (50mm Unmounted)\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\"\u003ei' Sloan Filter (50mm Unmounted)\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\"\u003ez' Sloan Filter (50mm Unmounted)\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\nContact us for warranty details.\n\u003c\/li\u003e\n\u003c\/ul\u003e","brand":"Antlia","offers":[{"title":"50mm Round Unmounted","offer_id":51932625764637,"sku":"ANT-PHOTOMETRICS-SLOAN-RD50","price":1400.0,"currency_code":"USD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0753\/5280\/1565\/files\/antlia-src-oyY_StQQwsAk4sAk_d78b00ed-c224-467b-b4a6-8af36a347dea.jpg?v=1792550001","url":"https:\/\/davidastro.com\/fr-int\/products\/antlia-photometrics-sloan-griz-4pcs-filter-set","provider":"David Astro","version":"1.0","type":"link"}