{"title":"Filters","description":"\u003cdiv\u003e\n  \u003cp\u003e\n    A filter decides what light reaches your sensor or your eye, and under Canadian suburban skies that decision often matters more than aperture. The right narrowband filter can make a nebula imageable from a driveway that visually shows almost nothing. David Astro carries filters in Canada — narrowband, LRGB, light pollution, planetary, solar and scientific — in 1.25\", 2\", 31 mm, 36 mm and unmounted formats, shipped from Canadian stock.\n  \u003c\/p\u003e\n  \u003cp\u003e\n    Filter selection is where our team spends a lot of time, because bandwidth, f-ratio and sensor size interact in ways that are not obvious from a product page. Tell us your telescope and camera and we will recommend a set that works together.\n  \u003c\/p\u003e\n\u003c\/div\u003e\n\u003c!-- more --\u003e\n\u003cdiv\u003e\n  \u003ch2\u003eFilter Types and When Each One Earns Its Place\u003c\/h2\u003e\n  \u003cp\u003e\n    Filters do not add signal. They remove unwanted light so that the signal you want has better contrast against the background. Choosing well means knowing which unwanted light you are fighting.\n  \u003c\/p\u003e\n  \u003cul\u003e\n    \u003cli\u003e\n\u003cstrong\u003e\u003ca href=\"\/collections\/narrowband-filters\"\u003eNarrowband filters:\u003c\/a\u003e\u003c\/strong\u003e Ha, OIII and SII passbands, typically 3 to 12 nm. Narrower bands reject more light pollution and moonlight but demand accurate focus and longer exposures.\u003c\/li\u003e\n    \u003cli\u003e\n\u003cstrong\u003e\u003ca href=\"\/collections\/lrgb-filters\"\u003eLRGB filter sets:\u003c\/a\u003e\u003c\/strong\u003e Parfocal luminance, red, green and blue for colour imaging with monochrome sensors, with the luminance channel carrying most of the detail.\u003c\/li\u003e\n    \u003cli\u003e\n\u003cstrong\u003e\u003ca href=\"\/collections\/light-pollution-filters-1\"\u003eLight pollution filters:\u003c\/a\u003e\u003c\/strong\u003e Broadband rejection of mercury and sodium emission lines. Effective against older street lighting and much less effective against broad-spectrum LED.\u003c\/li\u003e\n    \u003cli\u003e\n\u003cstrong\u003e\u003ca href=\"\/collections\/planetary-filters\"\u003ePlanetary and colour filters:\u003c\/a\u003e\u003c\/strong\u003e Wratten-standard colour filters that raise contrast on specific planetary features — a red or orange filter on Mars, blue on Jupiter's belts.\u003c\/li\u003e\n    \u003cli\u003e\n\u003cstrong\u003e\u003ca href=\"\/collections\/white-light\"\u003eSolar filters:\u003c\/a\u003e\u003c\/strong\u003e Full-aperture white-light filters for safe observation of sunspots and transits.\u003c\/li\u003e\n    \u003cli\u003e\n\u003cstrong\u003e\u003ca href=\"\/collections\/neutral-density-and-polarizing-filters\"\u003eNeutral density and polarizing:\u003c\/a\u003e\u003c\/strong\u003e Variable brightness reduction for lunar observing without altering colour balance.\u003c\/li\u003e\n  \u003c\/ul\u003e\n\u003c\/div\u003e\n\u003cdiv\u003e\n  \u003ch2\u003eWhy Choose David Astro for Filters\u003c\/h2\u003e\n  \u003cp\u003e\n    A filter that performs beautifully at f\/7 can produce a shifted passband and soft results at f\/3. That is the kind of detail worth asking about before ordering.\n  \u003c\/p\u003e\n  \u003cul\u003e\n    \u003cli\u003e\n\u003cstrong\u003eF-ratio matched recommendations:\u003c\/strong\u003e Narrowband passbands shift blueward in fast optical systems, so we recommend filters specified for your focal ratio rather than the narrowest available.\u003c\/li\u003e\n    \u003cli\u003e\n\u003cstrong\u003eSensor size and vignetting:\u003c\/strong\u003e We size filters to your sensor diagonal and filter wheel placement, so an undersized filter does not clip your corners.\u003c\/li\u003e\n    \u003cli\u003e\n\u003cstrong\u003eSpacing accounted for:\u003c\/strong\u003e Filter glass shifts focus by roughly a third of its thickness, and we include that in the back-focus calculation we provide.\u003c\/li\u003e\n    \u003cli\u003e\n\u003cstrong\u003eAuthorized dealer:\u003c\/strong\u003e Genuine filters with full manufacturer warranty and verified coatings, in Canadian inventory and shipped domestically.\u003c\/li\u003e\n    \u003cli\u003e\n\u003cstrong\u003eShips from Canada:\u003c\/strong\u003e No duties or brokerage charges for Canadian buyers.\u003c\/li\u003e\n  \u003c\/ul\u003e\n\u003c\/div\u003e\n\u003cdiv\u003e\n  \u003ch2\u003eFilters in Canada — Frequently Asked Questions\u003c\/h2\u003e\n  \u003cdl\u003e\n    \u003cdt\u003e\u003cstrong\u003eDo light pollution filters still work under LED streetlights?\u003c\/strong\u003e\u003c\/dt\u003e\n    \u003cdd\u003eMuch less well than they did under sodium lighting. LED emits across a broad spectrum, so there is no narrow band to reject. Narrowband filters remain effective because they pass only emission lines regardless of what the streetlight does.\u003c\/dd\u003e\n    \u003cdt\u003e\u003cstrong\u003eHow narrow should my Ha filter be?\u003c\/strong\u003e\u003c\/dt\u003e\n    \u003cdd\u003eFor f\/5 and slower, 3 to 5 nm gives excellent contrast. Below about f\/4, the incident light cone shifts the passband and a 6 to 7 nm filter, or one specified for fast optics, performs better.\u003c\/dd\u003e\n    \u003cdt\u003e\u003cstrong\u003eWhat size filters do I need?\u003c\/strong\u003e\u003c\/dt\u003e\n    \u003cdd\u003eMatch the sensor diagonal plus the distance from filter to sensor. A 36 mm filter typically covers APS-C in a standard wheel; full frame usually needs 50 mm square or unmounted 2 inch.\u003c\/dd\u003e\n    \u003cdt\u003e\u003cstrong\u003eAre filters shipped from Canada?\u003c\/strong\u003e\u003c\/dt\u003e\n    \u003cdd\u003eYes, in-stock filters are held in our Canadian warehouse and reach Canadian customers without customs handling.\u003c\/dd\u003e\n  \u003c\/dl\u003e\n\u003c\/div\u003e\n\u003cdiv\u003e\n  \u003ch2\u003eBuilding a filter set?\u003c\/h2\u003e\n  \u003cp\u003eTell us your telescope, camera and sky conditions and we will recommend the right bandwidths and sizes. Canadian stock, fast domestic shipping.\u003c\/p\u003e\n\u003c\/div\u003e","products":[{"product_id":"celestron-oxygen-iii-narrowband-filter-1-25-in","title":"Celestron Oxygen III Narrowband Filter - 1.25 in","description":"\u003cul class=\"DAV-feature-list\"\u003e\n\u003cli\u003eIsolates doubly-ionized oxygen lines (496nm and 501nm)\u003c\/li\u003e\n\u003cli\u003eProvides extreme contrast for planetary and emission nebulae\u003c\/li\u003e\n\u003cli\u003eBlocks the entire visual spectrum from 400nm to 700nm\u003c\/li\u003e\n\u003cli\u003eUltra-hard, vacuum-deposited coatings prevent halos on bright stars\u003c\/li\u003e\n\u003cli\u003eStandard 1.25\" threaded barrel\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\u003eCelestron Oxygen III Narrowband Filter - 1.25\"\u003c\/h2\u003e\n\u003cp\u003eThe Celestron Oxygen III Narrowband Filter for 1.25\" eyepieces isolates the critical 496nm and 501nm wavelengths emitted by planetary and emission nebulae, delivering a dramatic increase in contrast. By aggressively blocking the rest of the visual spectrum from 400nm to 700nm, this filter renders the sky background nearly black, allowing the faint, detailed structures of nebulae to become visible. Its ultra-hard, vacuum-deposited coatings are engineered to eliminate the unnatural colored halos around bright stars that can compromise views with less advanced filters.\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\u003eIsolating the 496nm \u0026amp; 501nm OIII Lines for Maximum Contrast\u003c\/h3\u003e\n\u003cp\u003eMany of the most sought-after celestial objects, including the Veil, Ring (M57), and Orion (M42) nebulae, radiate strongly in the green-blue light of doubly-ionized oxygen (OIII). This filter acts as a gateway, passing only these two specific spectral lines at 496nm and 501nm. This narrowband approach rejects light pollution, natural skyglow, and even the light from surrounding stars, causing faint nebular structures to stand out with striking clarity.\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\u003eAdvanced Coatings: Blocking the 400-700nm Spectrum to Eliminate Halos\u003c\/h3\u003e\n\u003cp\u003eA common issue with inferior nebula filters is the appearance of bright, colored halos around stars, an artifact of imprecise coating technology. Celestron's OIII filter uses ultra-hard, vacuum-deposited coatings that provide complete rejection of the visual spectrum from 400nm to 700nm outside the narrow OIII bandpass. This careful engineering ensures that bright stars remain tight, point-like sources without distracting artifacts, preserving the natural beauty of the starfield.\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\u003eCelestron OIII vs. UHC Filters: Choosing the Right Tool for the Target\u003c\/h3\u003e\n\u003cp\u003eAn OIII filter is a specialist's tool, while a UHC (Ultra High Contrast) filter is a generalist. The Celestron OIII provides the highest possible contrast on objects that are rich in Oxygen-III emissions, like the Dumbbell Nebula (M27) or the Crescent Nebula (NGC 6888). A UHC filter has a broader bandpass that also includes Hydrogen-Beta light, making it useful on a wider variety of nebulae but with less pronounced contrast on OIII-specific targets. For revealing the faintest details in planetary nebulae, the OIII is the superior choice.\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 purpose of the Celestron Oxygen III 1.25\" filter?\u003c\/h3\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion-A\"\u003e\n\u003cp\u003eIts primary purpose is to dramatically increase the contrast of specific celestial objects—namely \u003cstrong\u003eplanetary and emission nebulae\u003c\/strong\u003e—by isolating the two wavelengths of light (496nm and 501nm) they predominantly emit. This makes faint details, like the filaments in the Veil Nebula, much easier to see, especially from light-polluted locations.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion\"\u003e\n\u003ch3 class=\"DAV-accordion-Q\"\u003eHow will the Celestron OIII filter improve my view of the Orion Nebula (M42) in an 8\" SCT?\u003c\/h3\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion-A\"\u003e\n\u003cp\u003eIn an 8\" Schmidt-Cassegrain Telescope, the Celestron OIII filter will suppress the brightness of the Trapezium stars at the core of the Orion Nebula (M42), reducing glare and revealing the delicate, interwoven structures of the surrounding gas clouds. You'll be able to trace the intricate loops and wisps of nebulosity that are normally overwhelmed by the brilliance of the central stars.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion\"\u003e\n\u003ch3 class=\"DAV-accordion-Q\"\u003eCan I see the Ring Nebula (M57) from my suburban backyard with this OIII filter?\u003c\/h3\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion-A\"\u003e\n\u003cp\u003eYes, the Ring Nebula (M57) is an excellent target for this filter. From a suburban location, the filter will darken the bright sky background, making the \"donut\" shape of the nebula pop into view with much greater contrast. It will also make it easier to detect the faint central star under steady seeing conditions.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion\"\u003e\n\u003ch3 class=\"DAV-accordion-Q\"\u003eWill this filter make stars disappear?\u003c\/h3\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion-A\"\u003e\n\u003cp\u003eThe filter will significantly dim most stars, which is intentional. Stars emit light across the entire spectrum, and the filter blocks almost all of it. This dimming effect is what enhances the contrast of the nebula, which shines brightly in the specific OIII wavelengths that the filter transmits.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion\"\u003e\n\u003ch3 class=\"DAV-accordion-Q\"\u003eIs the Celestron OIII filter useful for viewing galaxies?\u003c\/h3\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion-A\"\u003e\n\u003cp\u003eNo, this filter is not recommended for galaxies. Galaxies like Andromeda (M31) are broadband objects, meaning they emit light across the entire visible spectrum. An OIII filter would block almost all of that light, making the galaxy invisible or extremely dim. For galaxies, a light pollution reduction (LPR) filter or no filter is best.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion\"\u003e\n\u003ch3 class=\"DAV-accordion-Q\"\u003eCan I use the Celestron 1.25\" OIII filter for astrophotography?\u003c\/h3\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion-A\"\u003e\n\u003cp\u003eWhile designed for visual use, this filter can be used for imaging, particularly with monochrome cameras. It serves as the \"O\" in an \"SHO\" (Hubble palette) image, isolating the Oxygen-III data. For color cameras, a multi-bandpass filter is often a more efficient choice, but this filter will work to capture OIII signal.\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\u003eNarrowband Interference Filter\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eDesignation\u003c\/td\u003e\n\u003ctd\u003eOxygen-III (OIII)\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eSize\u003c\/td\u003e\n\u003ctd\u003e1.25\"\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003ePrimary Bandpass\u003c\/td\u003e\n\u003ctd\u003e496nm and 501nm\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eBlocking Range\u003c\/td\u003e\n\u003ctd\u003e400nm - 700nm (full visual spectrum outside of bandpass)\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eCoatings\u003c\/td\u003e\n\u003ctd\u003eUltra-hard, multi-layer, vacuum-deposited\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eThreads\u003c\/td\u003e\n\u003ctd\u003eStandard 1.25\" filter threads (M28.5 x 0.6)\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eWarranty\u003c\/td\u003e\n\u003ctd\u003e2-Year Warranty\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\"\u003eCelestron Oxygen III Narrowband Filter - 1.25\"\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\"\u003eProtective Plastic Case\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\n\u003cul class=\"DAV-grid\"\u003e\n\u003cli class=\"DAV-grid-item\"\u003e\u003ca href=\"https:\/\/www.celestron.com\/pages\/drivers-and-software\" target=\"_blank\"\u003e\u003csvg xmlns=\"http:\/\/www.w3.org\/2000\/svg\" viewbox=\"0 0 640 512\" class=\"DAV-img-box\"\u003e\u003cpath fill=\"#0047a7\" d=\"M128 32C92.7 32 64 60.7 64 96l0 256 64 0 0-256 384 0 0 256 64 0 0-256c0-35.3-28.7-64-64-64L128 32zM19.2 384C8.6 384 0 392.6 0 403.2C0 445.6 34.4 480 76.8 480l486.4 0c42.4 0 76.8-34.4 76.8-76.8c0-10.6-8.6-19.2-19.2-19.2L19.2 384z\"\u003e\u003c\/path\u003e\u003c\/svg\u003e \n\u003cdiv\u003e\n\u003cp class=\"DAV-item-title\"\u003eDownload Software\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\u003ca href=\"https:\/\/davidastro.com\/pages\/celestron-warranty-policy\" rel=\"noopener\" target=\"_blank\"\u003eCelestron 2-Year Warranty\u003c\/a\u003e\u003c\/li\u003e\n\u003c\/ul\u003e","brand":"Celestron","offers":[{"title":"Default Title","offer_id":44967149338909,"sku":"CEL-93623","price":132.0,"currency_code":"CAD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0753\/5280\/1565\/products\/Celestron-Oxygen-III-Narrowband-Filter-1-25-in-93623-1__27739.1594230265.1280.1280.jpg?v=1684337235"},{"product_id":"celestron-oxygen-iii-narrowband-filter-2-in","title":"Celestron Oxygen III Narrowband Filter - 2 in","description":"\u003cul class=\"DAV-feature-list\"\u003e\n\u003cli\u003eIsolates the 496nm and 501nm Oxygen III wavelengths\u003c\/li\u003e\n\u003cli\u003eBlocks the entire visual spectrum from 400nm to 700nm\u003c\/li\u003e\n\u003cli\u003eUltra-hard, vacuum-deposited coatings prevent halos\u003c\/li\u003e\n\u003cli\u003eStandard 2\" filter threads\u003c\/li\u003e\n\u003cli\u003e2-Year Warranty\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\u003eCelestron Oxygen III Narrowband Filter - 2\"\u003c\/h2\u003e\n\u003cp\u003eThe Celestron Oxygen III Narrowband Filter - 2\" is engineered to pass only the critical 496nm and 501nm wavelengths characteristic of doubly-ionized oxygen. By aggressively blocking the rest of the visual spectrum from 400nm to 700nm, it creates extreme contrast for viewing and imaging planetary and emission nebulae. This filter comes with a 2-Year Warranty, ensuring its advanced coatings perform session after session.\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\u003eIsolating the 496nm \u0026amp; 501nm OIII Signal\u003c\/h3\u003e\n\u003cp\u003eThe faint, intricate structures within emission nebulae like the Veil Nebula or the Crescent Nebula are revealed primarily through the light of excited oxygen atoms. This filter isolates just the two OIII emission lines at 496nm and 501nm, effectively turning off the light from other sources, including light pollution and even the stars themselves. The result is a dramatic increase in contrast, allowing the delicate filaments and shells of these objects to stand out against a truly black sky background.\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 400-700nm Stoplight for Unwanted Star Halos\u003c\/h3\u003e\n\u003cp\u003eUnlike simpler filters, the Celestron OIII uses ultra-hard, vacuum-deposited coatings to block the entire visual spectrum from 400nm to 700nm. This meticulous approach to light suppression does more than just darken the sky—it eliminates the unnatural, colored halos that can appear around bright stars in less sophisticated designs. Your starfields remain sharp and natural, ensuring the nebula, not distracting artifacts, is the focus of your view.\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\"\u003eHow does the Celestron 2\" OIII filter improve views of the Veil Nebula?\u003c\/h3\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion-A\"\u003e\n\u003cp\u003eThe Veil Nebula is a classic supernova remnant that shines almost exclusively in Oxygen III and Hydrogen-alpha light. By isolating the OIII lines at \u003cstrong\u003e496nm and 501nm\u003c\/strong\u003e, this filter dramatically darkens the sky background, making the faint, thread-like filaments of the nebula appear significantly brighter and more detailed, even from moderately light-polluted skies.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion\"\u003e\n\u003ch3 class=\"DAV-accordion-Q\"\u003eCan I use the Celestron Oxygen III filter for imaging the Orion Nebula (M42) from my backyard?\u003c\/h3\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion-A\"\u003e\n\u003cp\u003eYes, this is an excellent application for the filter. The core of the Orion Nebula is rich in OIII emission. Using the Celestron OIII filter will help you capture the intricate details within the Trapezium region and the surrounding nebulosity by rejecting broadband light pollution and reducing the overwhelming brightness of the nebula's stars.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion\"\u003e\n\u003ch3 class=\"DAV-accordion-Q\"\u003eWill this Celestron OIII filter help me see galaxies or star clusters?\u003c\/h3\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion-A\"\u003e\n\u003cp\u003eNo, this filter is not designed for broadband targets like galaxies and star clusters. These objects emit light across the entire visual spectrum. The OIII filter will block almost all of their light, making them extremely dim or completely invisible. It is a specialized tool exclusively for emission and planetary nebulae.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion\"\u003e\n\u003ch3 class=\"DAV-accordion-Q\"\u003eWhat is the advantage of blocking the spectrum from 400nm to 700nm?\u003c\/h3\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion-A\"\u003e\n\u003cp\u003eThis comprehensive blocking ensures maximum contrast by eliminating all sources of visual light except for the targeted OIII wavelengths. A key benefit of this design is the prevention of bloated stars and colored halos, which can occur when filters have \"leaks\" or less precise cutoff points, leading to cleaner and more aesthetically pleasing astrophotos.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion\"\u003e\n\u003ch3 class=\"DAV-accordion-Q\"\u003eIs the Celestron 2\" OIII filter threaded for standard eyepieces and accessories?\u003c\/h3\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion-A\"\u003e\n\u003cp\u003eYes. The Celestron Oxygen III Narrowband Filter - 2\" is housed in a standard 2-inch cell with M48x0.75 threads. It will screw directly into the barrel of any 2\" eyepiece, diagonal, or imaging accessory that accepts standard 2\" filters.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion\"\u003e\n\u003ch3 class=\"DAV-accordion-Q\"\u003eWhy are there two passbands at 496nm and 501nm?\u003c\/h3\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion-A\"\u003e\n\u003cp\u003eDoubly-ionized oxygen naturally emits light at both of these very close wavelengths. A high-quality OIII filter is designed to pass both lines to maximize the signal gathered from the nebula, resulting in a brighter and more detailed image than a filter that might only capture one.\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 Size\u003c\/td\u003e\n\u003ctd\u003e2\"\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003ePrimary Wavelengths\u003c\/td\u003e\n\u003ctd\u003e496nm \u0026amp; 501nm (Doubly-ionized Oxygen)\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eBlocking Range\u003c\/td\u003e\n\u003ctd\u003e400nm - 700nm\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eCoatings\u003c\/td\u003e\n\u003ctd\u003eUltra-hard, multi-layer, vacuum-deposited\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eThreads\u003c\/td\u003e\n\u003ctd\u003eM48x0.75\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eWarranty\u003c\/td\u003e\n\u003ctd\u003e2-Year Warranty\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\"\u003eCelestron Oxygen III Narrowband Filter - 2\"\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\"\u003eProtective case\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\u003ca href=\"https:\/\/davidastro.com\/pages\/celestron-warranty-policy\" rel=\"noopener\" target=\"_blank\"\u003eCelestron 2-Year Limited Warranty\u003c\/a\u003e\u003c\/li\u003e\n\u003c\/ul\u003e","brand":"Celestron","offers":[{"title":"Default Title","offer_id":44967149371677,"sku":"CEL-93624","price":174.0,"currency_code":"CAD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0753\/5280\/1565\/products\/Celestron-Oxygen-III-Narrowband-Filter-2-in-93624-1__08282.1594230265.1280.1280.jpg?v=1684337236"},{"product_id":"celestron-uhc-lpr-filter-1-25","title":"Celestron UHC\/LPR Filter - 1.25\"","description":"\u003cul class=\"DAV-feature-list\"\u003e\n\u003cli\u003eSelectively blocks mercury vapor, sodium vapor, and natural sky glow\u003c\/li\u003e\n\u003cli\u003eAchieves over 97% transmission of critical nebula emission lines\u003c\/li\u003e\n\u003cli\u003eFeatures a moderate 60nm passband for natural views with high contrast\u003c\/li\u003e\n\u003cli\u003eEfficient H-Alpha passband at 656nm for astrophotography\u003c\/li\u003e\n\u003cli\u003eSized for standard 1.25\" eyepieces and 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\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\u003eCelestron UHC\/LPR Filter - 1.25\"\u003c\/h2\u003e\n\u003cp\u003eThe Celestron UHC\/LPR Filter for 1.25\" eyepieces delivers a dramatic increase in contrast by achieving over 97% transmission of key nebula wavelengths while suppressing common light pollution. Its 60nm passband provides a significant boost for telescopes in the 4\" to 11\" aperture range, darkening the sky without eliminating background star fields. This filter also includes an efficient H-Alpha passband at 656nm, making it a valuable tool for both visual observers and imagers.\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\u003eBlocking Unwanted Light with \u0026gt;97% Transmission\u003c\/h3\u003e\n\u003cp\u003eThis Ultra High Contrast (UHC) filter is engineered to isolate and reject specific wavelengths associated with urban skyglow—primarily from mercury and sodium-vapor streetlights—and the neutral oxygen that causes natural sky glow. While aggressively blocking these sources, the advanced multi-layer dielectric coatings allow more than 97% of the light from emission nebulae to pass through. The result is a significantly darker background sky, making faint structures in objects like the Orion Nebula (M42) or Lagoon Nebula (M8) pop into view.\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\u003eIonbeam-Hardened Durability for 1.25\" Barrels\u003c\/h3\u003e\n\u003cp\u003eCelestron employs plasma-assisted, Ionbeam-hardened coatings on the UHC\/LPR filter, creating an optical surface that is highly resistant to scratching and degradation from cleaning and environmental exposure. This modern coating technology ensures the filter's high transmission and sharp cutoffs are maintained for years of use. The precisely machined 1.25\" aluminum cell threads smoothly onto standard eyepieces, diagonals, and camera nosepieces without binding.\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 60nm Passband Optimized for Nebulae\u003c\/h3\u003e\n\u003cp\u003eThe filter's 60nm passband strikes a critical balance, offering a major contrast enhancement while maintaining a more natural-feeling view compared to ultra-narrowband filters. This moderate bandwidth allows enough of the stellar continuum through to keep star fields rich, which is especially appreciated by users of 4\" to 11\" telescopes. For imagers, the inclusion of the critical 656nm H-Alpha line means you can capture vital hydrogen-alpha data without needing a separate, dedicated filter.\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\"\u003eHow will the Celestron UHC\/LPR 1.25\" filter improve my view of the Orion Nebula (M42) from the city?\u003c\/h3\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion-A\"\u003e\n\u003cp\u003eFrom a light-polluted location, the Celestron UHC\/LPR filter will dramatically darken the greyish background sky, increasing the contrast between the nebula and its surroundings. This allows you to see fainter, extended structures in M42's outer wings and resolve more detail within the bright core of the Trapezium that would otherwise be washed out by city lights.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion\"\u003e\n\u003ch3 class=\"DAV-accordion-Q\"\u003eIs this 1.25\" filter a good choice for my 8\" Schmidt-Cassegrain telescope?\u003c\/h3\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion-A\"\u003e\n\u003cp\u003eAbsolutely. Telescopes in the 4\" to 11\" range benefit significantly from this filter. On an 8\" SCT, the UHC\/LPR filter will provide a substantial contrast boost on emission and planetary nebulae without making the image too dim, preserving the brightness advantage of your telescope's aperture.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion\"\u003e\n\u003ch3 class=\"DAV-accordion-Q\"\u003eWhat is the difference between this Celestron UHC\/LPR filter and a broadband filter?\u003c\/h3\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion-A\"\u003e\n\u003cp\u003eA UHC (Ultra High Contrast) filter like this one has a narrower passband (around 60nm) than a typical broadband or \"minus-violet\" filter. It more aggressively targets specific light pollution lines, resulting in a darker sky background and noticeably higher contrast on emission nebulae. Broadband filters offer a more subtle effect with a more natural color balance.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion\"\u003e\n\u003ch3 class=\"DAV-accordion-Q\"\u003eCan I use the Celestron UHC\/LPR filter for astrophotography?\u003c\/h3\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion-A\"\u003e\n\u003cp\u003eYes, this filter is designed for both visual and imaging use. Its key advantage for imagers is the inclusion of an efficient H-Alpha passband at 656nm, allowing you to capture crucial red nebulosity with a color camera in a single shot, which many LPR filters block.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion\"\u003e\n\u003ch3 class=\"DAV-accordion-Q\"\u003eWill this filter help me see galaxies better?\u003c\/h3\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion-A\"\u003e\n\u003cp\u003eNo, this filter is not recommended for galaxies. Galaxies are broadband objects, meaning they emit light across the entire visible spectrum. A UHC\/LPR filter works by blocking parts of that spectrum, which will dim the view of the galaxy as much as it dims the light pollution. It is designed specifically for emission nebulae.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion\"\u003e\n\u003ch3 class=\"DAV-accordion-Q\"\u003eWhat specific types of artificial light does the UHC\/LPR filter block?\u003c\/h3\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion-A\"\u003e\n\u003cp\u003eThe filter is designed to combat the most common sources of urban light pollution. This includes \u003cstrong\u003emercury vapor lights\u003c\/strong\u003e, \u003cstrong\u003ehigh-pressure sodium vapor lights\u003c\/strong\u003e, and \u003cstrong\u003elow-pressure sodium vapor lights\u003c\/strong\u003e. It also reduces the effects of natural \u003cstrong\u003esky glow\u003c\/strong\u003e caused by neutral oxygen emission.\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\u003eUHC\/LPR (Ultra High Contrast \/ Light Pollution Reduction)\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eBarrel Size\u003c\/td\u003e\n\u003ctd\u003e1.25\"\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003ePeak Transmission\u003c\/td\u003e\n\u003ctd\u003e\u0026gt;97%\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003ePassband\u003c\/td\u003e\n\u003ctd\u003e60nm\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eH-Alpha Passband\u003c\/td\u003e\n\u003ctd\u003e656nm\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eCoatings\u003c\/td\u003e\n\u003ctd\u003eMulti-layer dielectric, plasma assisted, Ionbeam hardened\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eRecommended Aperture\u003c\/td\u003e\n\u003ctd\u003e4\" - 11\" (102mm - 280mm)\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eWarranty\u003c\/td\u003e\n\u003ctd\u003e2-Year Warranty\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\u003cimg class=\"DAV-img-box\" alt=\"Celestron UHC\/LPR Filter - 1.25\" src=\"https:\/\/cdn.shopify.com\/s\/files\/1\/0753\/5280\/1565\/products\/F7424-A_uhc_lpr_filter_125_1.jpg?v=1680126759\"\u003e\n\u003cdiv\u003e\n\u003cp class=\"DAV-item-title\"\u003eUHC\/LPR Filter - 1.25\"\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\u003cimg class=\"DAV-img-box\" alt=\"Protective case for 1.25-inch filter\" src=\"https:\/\/cdn.shopify.com\/s\/files\/1\/0753\/5280\/1565\/files\/zwo-1-25-inch-filter-case.jpg?v=1782035905\"\u003e\n\u003cdiv\u003e\n\u003cp class=\"DAV-item-title\"\u003eProtective Case\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\u003ca href=\"https:\/\/davidastro.com\/pages\/celestron-warranty-policy\" rel=\"noopener\" target=\"_blank\"\u003eCelestron 2-Year Limited Warranty\u003c\/a\u003e\u003c\/li\u003e\n\u003c\/ul\u003e","brand":"Celestron","offers":[{"title":"Default Title","offer_id":44967149404445,"sku":"CEL-94123","price":132.0,"currency_code":"CAD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0753\/5280\/1565\/products\/Celestron-UHC-LPR-Filter-1-25-in-94123-1__39582.1594230266.1280.1280.jpg?v=1684337240"},{"product_id":"celestron-uhc-lpr-filter-2","title":"Celestron UHC\/LPR Filter - 2\"","description":"\u003cul class=\"DAV-feature-list\"\u003e\n\u003cli\u003eSelectively blocks light pollution from mercury and sodium vapor lights\u003c\/li\u003e\n\u003cli\u003eAchieves over 97% light transmission for maximum brightness\u003c\/li\u003e\n\u003cli\u003e60nm bandpass enhances nebula contrast while maintaining natural star fields\u003c\/li\u003e\n\u003cli\u003eOptimized for 2\" focusers and accessories\u003c\/li\u003e\n\u003cli\u003eIonbeam-hardened coatings for scratch resistance and durability\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\u003eCelestron UHC\/LPR Filter - 2\"\u003c\/h2\u003e\n\u003cp\u003eThe Celestron UHC\/LPR Filter for 2\" eyepieces dramatically increases contrast by selectively blocking artificial light pollution and natural sky glow, achieving over 97% transmission of critical nebula wavelengths within its 60nm passband. Optimized for telescopes from 4\" to 11\" in aperture, it darkens the sky background and includes a specific passband for the 656nm H-Alpha line, making faint emission structures visible from the city or deep-sky sites.\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\u003eBlocking Key Light Pollution Lines in 4\" to 11\" Telescopes\u003c\/h3\u003e\n\u003cp\u003eThis Ultra High Contrast (UHC) filter is engineered to reject the specific wavelengths produced by mercury vapor, high and low-pressure sodium vapor lights, and the neutral oxygen emission that causes natural sky glow. By eliminating this unwanted light, the background sky appears significantly darker, allowing the faint light from emission nebulae to stand out. This targeted rejection is effective in telescopes from 4\" to 11\" in aperture, where maximizing every photon is critical.\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 60nm Passband Delivering \u0026gt;97% Peak Transmission\u003c\/h3\u003e\n\u003cp\u003eThe filter's design centers on a moderately wide 60nm passband, which allows it to boost nebula contrast without sacrificing a natural-looking star field. Within this window, advanced multi-layer dielectric coatings achieve a peak transmission of over 97%. This high efficiency ensures that views remain bright and detailed, preventing the dimming effect that can occur with less advanced filters and making it an ideal choice for smaller telescopes.\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\u003eHardened Coatings and a 656nm H-Alpha Passband for Imagers\u003c\/h3\u003e\n\u003cp\u003eCelestron utilizes plasma-assisted and Ionbeam-hardened coatings, creating a durable, scratch-resistant surface that withstands regular use and cleaning. For astrophotographers, the filter's design is especially valuable as it includes an efficient passband for the critical H-Alpha emission line at 656nm. This allows DSLR and color camera users to capture the deep reds of hydrogen-rich nebulae that are often lost in city light.\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\u003eUHC\/LPR vs. Standard Broadband Filters: A Clear Contrast Advantage\u003c\/h3\u003e\n\u003cp\u003eCompared to a typical broadband Light Pollution Reduction (LPR) filter, the Celestron UHC\/LPR provides a noticeable improvement in contrast on emission and planetary nebulae. While a broadband filter offers a more general reduction of light pollution, the UHC design more aggressively targets specific nuisance wavelengths.\u003c\/p\u003e\n\u003cul\u003e\n\u003cli\u003e\n\u003cstrong\u003eSky Background:\u003c\/strong\u003e The sky view through the UHC\/LPR is significantly darker, making it easier to detect the faint, extended structures of objects like the Veil Nebula (NGC 6960).\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eNebula Detail:\u003c\/strong\u003e Emission nebulae appear more defined and \"pop\" from the background, revealing subtle shadings and structures that are washed out with a less selective filter.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eNatural View:\u003c\/strong\u003e The 60nm passband is wide enough to maintain relatively natural star colors, avoiding the heavy color cast associated with extremely narrow \"line\" filters.\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\"\u003eWhat is the difference between this Celestron UHC\/LPR and a standard broadband filter?\u003c\/h3\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion-A\"\u003e\n\u003cp\u003eThe Celestron \u003cstrong\u003eUHC\/LPR (Ultra High Contrast\/Light Pollution Reduction)\u003c\/strong\u003e filter has a narrower passband (around 60nm) that more aggressively isolates the key wavelengths from emission nebulae while strongly rejecting light pollution. A standard broadband filter has a wider passband, resulting in a brighter but lower-contrast image. The UHC design produces a darker sky background and makes nebulae stand out more distinctly.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion\"\u003e\n\u003ch3 class=\"DAV-accordion-Q\"\u003eIs the Celestron UHC\/LPR filter only for viewing nebulae?\u003c\/h3\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion-A\"\u003e\n\u003cp\u003eWhile its primary purpose is to enhance emission, planetary, and reflection nebulae, it is not strictly limited to them. The filter can help darken the sky background and improve contrast on any deep-sky object, though the effect will be most dramatic on nebulae. It is not recommended for viewing galaxies or star clusters, as it will dim these objects without providing a significant contrast benefit.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion\"\u003e\n\u003ch3 class=\"DAV-accordion-Q\"\u003eWill this filter help me see the Orion Nebula (M42) from my suburban backyard with an 8\" SCT?\u003c\/h3\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion-A\"\u003e\n\u003cp\u003eAbsolutely. An 8\" SCT is an excellent instrument for this filter. The Celestron UHC\/LPR will significantly darken the washed-out suburban sky, dramatically improving the contrast of the Orion Nebula (M42). You will be able to see more of the faint, extended nebulosity and potentially resolve more detail within the Trapezium region.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion\"\u003e\n\u003ch3 class=\"DAV-accordion-Q\"\u003eI have a 6\" Newtonian at a dark sky site. Is the Celestron UHC\/LPR filter still useful?\u003c\/h3\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion-A\"\u003e\n\u003cp\u003eYes, even at a dark sky site, this filter is very effective. It works by blocking natural sky glow in addition to artificial light pollution. By using the filter on objects like the Lagoon Nebula (M8) or the Swan Nebula (M17), you will see a noticeable increase in contrast, making the nebulosity appear more detailed and defined against the blackness of space.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion\"\u003e\n\u003ch3 class=\"DAV-accordion-Q\"\u003eIs the Celestron 2\" UHC\/LPR filter suitable for astrophotography?\u003c\/h3\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion-A\"\u003e\n\u003cp\u003eYes, it is well-suited for imaging with color cameras like DSLRs or dedicated astronomy cameras. The filter's broader 60nm bandpass retains good star color, and its efficient transmission of the H-Alpha wavelength at 656nm is crucial for capturing the red emission regions in many popular deep-sky targets.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion\"\u003e\n\u003ch3 class=\"DAV-accordion-Q\"\u003eHow do I attach and use the 2\" UHC\/LPR filter?\u003c\/h3\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion-A\"\u003e\n\u003cp\u003eThe Celestron 2\" UHC\/LPR filter has standard 2\" filter threads (M48x0.75). It can be threaded directly onto the barrel of any 2\" eyepiece or onto a 2\" nosepiece for a camera. Simply screw it on until it is finger-tight and insert the eyepiece or camera into your telescope's focuser as usual.\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 Size\u003c\/td\u003e\n\u003ctd\u003e2\"\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eFilter Type\u003c\/td\u003e\n\u003ctd\u003eUHC\/LPR (Ultra High Contrast \/ Light Pollution Reduction)\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003ePeak Transmission\u003c\/td\u003e\n\u003ctd\u003e\u0026gt;97%\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003ePassband\u003c\/td\u003e\n\u003ctd\u003e60nm\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eH-Alpha Passband\u003c\/td\u003e\n\u003ctd\u003e656nm\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eCoatings\u003c\/td\u003e\n\u003ctd\u003eMulti-layer dielectric, Ionbeam hardened\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eRecommended Telescopes\u003c\/td\u003e\n\u003ctd\u003e4\" - 11\" aperture\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\u003cimg class=\"DAV-img-box\" alt=\"Celestron UHC\/LPR Filter - 2\" src=\"https:\/\/cdn.shopify.com\/s\/files\/1\/0753\/5280\/1565\/files\/celestron-uhc-lpr-filter-2.jpg?v=1782200231\"\u003e\n\u003cdiv\u003e\n\u003cp class=\"DAV-item-title\"\u003eUHC\/LPR Filter - 2\"\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\u003cimg class=\"DAV-img-box\" alt=\"Protective Plastic Case for 2-inch Filter\" src=\"https:\/\/cdn.shopify.com\/s\/files\/1\/0753\/5280\/1565\/files\/2-inch-filter-case.jpg?v=1782200231\"\u003e\n\u003cdiv\u003e\n\u003cp class=\"DAV-item-title\"\u003eProtective Plastic Case\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\n\u003cul class=\"DAV-grid\"\u003e\n\u003cli class=\"DAV-grid-item\"\u003e\u003ca href=\"https:\/\/www.celestron.com\/pages\/drivers-and-software\" target=\"_blank\"\u003e\u003csvg xmlns=\"http:\/\/www.w3.org\/2000\/svg\" viewbox=\"0 0 640 512\" class=\"DAV-img-box\"\u003e\u003cpath fill=\"#0047a7\" d=\"M128 32C92.7 32 64 60.7 64 96l0 256 64 0 0-256 384 0 0 256 64 0 0-256c0-35.3-28.7-64-64-64L128 32zM19.2 384C8.6 384 0 392.6 0 403.2C0 445.6 34.4 480 76.8 480l486.4 0c42.4 0 76.8-34.4 76.8-76.8c0-10.6-8.6-19.2-19.2-19.2L19.2 384z\"\u003e\u003c\/path\u003e\u003c\/svg\u003e\n\u003cdiv\u003e\n\u003cp class=\"DAV-item-title\"\u003eDownload Celestron Software\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\u003cp\u003eThis product is covered by Celestron's 2-Year Limited Warranty. For more details, please visit the \u003ca href=\"https:\/\/davidastro.com\/pages\/celestron-warranty-policy\" rel=\"noopener\" target=\"_blank\"\u003eCelestron Warranty Policy\u003c\/a\u003e page.\u003c\/p\u003e\n\u003c\/li\u003e\n\u003c\/ul\u003e","brand":"Celestron","offers":[{"title":"Default Title","offer_id":44967149437213,"sku":"CEL-94124","price":174.0,"currency_code":"CAD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0753\/5280\/1565\/products\/Celestron-UHC-LPR-Filter-2-in-94124-1__66083.1594230267.1280.1280.jpg?v=1684337242"},{"product_id":"celestron-moon-filter-1-25","title":"Celestron Moon Filter - 1.25\"","description":"\u003cul class=\"DAV-feature-list\"\u003e\n\u003cli\u003eReduces overwhelming brightness and glare from the Moon\u003c\/li\u003e\n\u003cli\u003eEnhances contrast to reveal finer surface details\u003c\/li\u003e\n\u003cli\u003eThreads directly onto most standard 1.25\" eyepieces\u003c\/li\u003e\n\u003cli\u003eImproves viewing comfort, especially near the full moon phase\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\u003eCelestron Moon Filter - 1.25\"\u003c\/h2\u003e\n\u003cp\u003eThe Celestron Moon Filter - 1.25\" is an essential accessory for observing our nearest celestial neighbor. By reducing the Moon's intense brightness, this filter allows your eye to relax and open up, revealing subtle details in crater walls, rilles, and mare that are otherwise lost to glare. Backed by a 2-year warranty, it simply threads onto any standard 1.25\" eyepiece to instantly improve your lunar viewing experience.\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\u003eReduce Glare and See More Detail on the Moon\u003c\/h3\u003e\n\u003cp\u003eViewing the Moon, especially when it is near full, can be uncomfortably bright through a telescope. Your eye reacts to the intense light by stopping down, which hides faint contrasts and washes out surface features. The Celestron Moon Filter acts like a pair of high-quality sunglasses for your telescope, dimming the view to a comfortable level and significantly increasing contrast between light and dark areas.\u003c\/p\u003e\n\u003cp\u003eThis reduction in glare is the key to unlocking finer details. With the filter in place, you can comfortably study the complex ejecta blankets around prominent craters, trace the delicate lines of sinuous rilles, and distinguish between the different lava flows that formed the lunar seas billions of years ago.\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\u003eSimple 1.25\" Thread-On Design for Instant Use\u003c\/h3\u003e\n\u003cp\u003eThis filter is designed for immediate and universal use. It features standard 1.25\" filter threads that screw directly onto the barrel of most 1.25\" eyepieces, regardless of the brand. Installation takes only a few seconds, transforming any of your standard eyepieces into a specialized tool for lunar observation.\u003c\/p\u003e\n\u003cul\u003e\n\u003cli\u003e\n\u003cstrong\u003eUniversal Fit:\u003c\/strong\u003e Compatible with any eyepiece that has a standard 1.25\" filter thread, making it a versatile addition to your accessory case.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eBeyond the Moon:\u003c\/strong\u003e The filter is also effective at cutting the glare from Venus, allowing you to more easily discern its phases. It can also be used to dim very bright terrestrial scenes during daytime observation.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eImportant Safety Note:\u003c\/strong\u003e This filter is designed for lunar and planetary viewing only. It is absolutely \u003cstrong\u003enot\u003c\/strong\u003e a solar filter and must never be used to observe the Sun.\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\u003eIs the Celestron 1.25\" Moon Filter Right for You?\u003c\/h3\u003e\n\u003cp\u003eIf you've ever found yourself squinting at the eyepiece while observing the Moon, this filter is a necessary accessory. It's the single most effective and affordable upgrade for anyone looking to move beyond casual glances and begin serious lunar exploration. For a minimal investment, you gain the ability to see more detail and observe for longer periods in greater comfort.\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\"\u003eWhy do I need a Celestron Moon Filter to observe the Moon?\u003c\/h3\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion-A\"\u003e\n\u003cp\u003eThe Moon is extremely bright through a telescope, especially around its full phase. This brightness causes your pupil to contract, hiding faint details and causing eye strain. The Celestron Moon Filter reduces the light to a comfortable level, which improves contrast and allows you to see much finer surface features like small craters and rilles.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion\"\u003e\n\u003ch3 class=\"DAV-accordion-Q\"\u003eWill the Celestron Moon Filter help me see the craters Copernicus and Tycho more clearly in my 6\" Newtonian?\u003c\/h3\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion-A\"\u003e\n\u003cp\u003eAbsolutely. For bright targets like Copernicus and the extensive ray system of Tycho, the filter will cut the overwhelming glare, making the crater walls, central peaks, and surrounding ejecta blankets stand out with much greater clarity. It allows you to study these features for longer periods without discomfort.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion\"\u003e\n\u003ch3 class=\"DAV-accordion-Q\"\u003eHow do I attach the 1.25\" Moon Filter to my eyepiece?\u003c\/h3\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion-A\"\u003e\n\u003cp\u003eThe filter simply screws into the threads on the bottom of the barrel of most standard 1.25\" eyepieces. Just unthread the eyepiece from your focuser or diagonal, attach the filter, and place the eyepiece back in. It takes only a few seconds.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion\"\u003e\n\u003ch3 class=\"DAV-accordion-Q\"\u003eDoes the Celestron Moon Filter change the color of the Moon?\u003c\/h3\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion-A\"\u003e\n\u003cp\u003eMost standard moon filters are neutral density filters, meaning they reduce brightness across the entire visual spectrum equally. This dims the view without introducing any significant color cast, preserving the Moon's natural grey and white tones.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion\"\u003e\n\u003ch3 class=\"DAV-accordion-Q\"\u003eCan I use the Celestron Moon Filter to see the phases of Venus?\u003c\/h3\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion-A\"\u003e\n\u003cp\u003eYes, the filter is very helpful for observing Venus. Venus is the brightest planet and its glare can make it difficult to see its phase clearly. The Moon Filter reduces this glare, providing a much sharper and more defined view of its crescent or gibbous shape.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion\"\u003e\n\u003ch3 class=\"DAV-accordion-Q\"\u003eCan I use this Celestron filter to look at the Sun?\u003c\/h3\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion-A\"\u003e\n\u003cp\u003e\u003cstrong\u003eNEVER.\u003c\/strong\u003e You must never use this Moon Filter, or any eyepiece filter, to view the Sun. It will not block the harmful infrared and ultraviolet radiation and will lead to immediate and permanent eye damage. Only use a certified solar filter that covers the entire front of your telescope.\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\u003eProduct Name\u003c\/td\u003e\n\u003ctd\u003eMoon Filter - 1.25\"\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eBarrel Size\u003c\/td\u003e\n\u003ctd\u003e1.25\"\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eWarranty\u003c\/td\u003e\n\u003ctd\u003e2-Year Warranty\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\"\u003eCelestron Moon Filter - 1.25\"\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\u003ca href=\"https:\/\/davidastro.com\/pages\/celestron-warranty-policy\" rel=\"noopener\" target=\"_blank\"\u003eCelestron 2-Year Warranty\u003c\/a\u003e\u003c\/li\u003e\n\u003c\/ul\u003e","brand":"Celestron","offers":[{"title":"Default Title","offer_id":44967149502749,"sku":"CEL-94119-A","price":18.0,"currency_code":"CAD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0753\/5280\/1565\/products\/Celestron-1-25-inch-Moon-Filter-94119-A-1__47885.1594231057.1280.1280.jpg?v=1684337244"},{"product_id":"celestron-neutral-density-moon-filter-1-25","title":"Celestron Neutral Density Moon Filter - 1.25\"","description":"\u003cul class=\"DAV-feature-list\"\u003e\n\u003cli\u003eReduces overwhelming brightness from the Moon and bright planets\u003c\/li\u003e\n\u003cli\u003eTransmits only 13% of incoming light for comfortable viewing\u003c\/li\u003e\n\u003cli\u003eFits all standard 1.25\" eyepieces and accessories\u003c\/li\u003e\n\u003cli\u003eNeutral density glass provides true-color views without color shifting\u003c\/li\u003e\n\u003cli\u003eStackable design allows use with other planetary filters\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\u003eCelestron Neutral Density Moon Filter - 1.25\"\u003c\/h2\u003e\n\u003cp\u003eThe Celestron Neutral Density Moon Filter for 1.25\" eyepieces makes lunar observing comfortable by cutting overwhelming glare with a specific 13% light transmission rate. This 6 g filter threads into a durable aluminum cell housing, preserving the Moon's natural colors without the tint introduced by color filters. Its stackable design allows you to combine it with other filters to enhance specific planetary features.\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\u003eReduce Lunar Glare with 13% Light Transmission\u003c\/h3\u003e\n\u003cp\u003eA bright Moon can easily wash out surface detail and cause significant eye strain, especially through a larger telescope. This filter solves the problem by blocking 87% of the incoming light, allowing only a comfortable 13% to pass through to your eye. This reduction in brightness reveals subtle features like crater rays, rilles, and maria that are otherwise lost in the glare, transforming an overpowering view into a detailed exploration.\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\u003eNeutral Density Design: A True-Color View of the Moon\u003c\/h3\u003e\n\u003cp\u003eUnlike simple colored filters that cut glare but also add an unnatural green or blue cast, this is a true neutral density filter. It reduces the brightness across the entire visible spectrum evenly, so the image you see is dimmed but not color-shifted. You see the Moon's subtle grays, browns, and whites exactly as they are, providing a more authentic and scientifically useful view than a basic #58 green filter can offer.\u003c\/p\u003e\n\u003cul\u003e\n\u003cli\u003e\n\u003cstrong\u003eAluminum Cell Housing:\u003c\/strong\u003e The 31mm x 11.5mm filter is housed in a precision-machined aluminum cell for durability and secure threading.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eStackable Threads:\u003c\/strong\u003e The cell is threaded on both sides, allowing you to stack it with other 1.25\" filters, such as a light blue filter to enhance detail on Jupiter while simultaneously cutting its glare.\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\u003eBeyond the Moon: Increasing Contrast on Planets and Double Stars\u003c\/h3\u003e\n\u003cp\u003eThis filter's utility isn't limited to the Moon. The 13% transmission is also highly effective for reducing the glare from bright planets like Venus and Jupiter, making it easier to spot faint cloud details or moons close to the planet's disk. For observers of binary stars, dimming a bright primary star can be the key to cleanly splitting a close, faint companion from its glare.\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\"\u003eWhy use a 13% transmission filter for the Celestron Moon Filter?\u003c\/h3\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion-A\"\u003e\n\u003cp\u003eA 13% transmission is considered the sweet spot for lunar viewing. It's dark enough to cut the painful glare of a full or gibbous Moon, especially in telescopes 6\" or larger, but not so dark that it extinguishes detail on dimmer crescent phases. It provides a comfortable, high-contrast view across the entire lunar cycle.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion\"\u003e\n\u003ch3 class=\"DAV-accordion-Q\"\u003eHow does the Celestron Neutral Density Moon Filter compare to a color filter like a #58 Green?\u003c\/h3\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion-A\"\u003e\n\u003cp\u003eWhile both reduce brightness, the Neutral Density filter provides a true-color image by dimming all wavelengths of light equally. A #58 Green filter absorbs red and blue light, creating an artificial green tint. For accurate lunar and planetary observing, the Neutral Density filter is superior.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion\"\u003e\n\u003ch3 class=\"DAV-accordion-Q\"\u003eCan I use this Celestron filter for viewing Venus's phases?\u003c\/h3\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion-A\"\u003e\n\u003cp\u003eAbsolutely. Venus is intensely bright, which often creates internal reflections and makes its subtle crescent phase difficult to see cleanly. This filter's 13% transmission cuts that glare significantly, providing a much sharper and more comfortable view of the planet's phases.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion\"\u003e\n\u003ch3 class=\"DAV-accordion-Q\"\u003eWill this 1.25\" filter help me split close double stars like Sirius?\u003c\/h3\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion-A\"\u003e\n\u003cp\u003eYes, it can be a very useful tool. The primary star in a pair like Sirius (Alpha Canis Majoris) can completely overwhelm its faint companion, the Pup. By reducing the primary's glare with this filter, you increase the effective contrast, making it easier for your eye to pick out the nearby companion star.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion\"\u003e\n\u003ch3 class=\"DAV-accordion-Q\"\u003eIs the Celestron Moon Filter stackable with other 1.25\" filters?\u003c\/h3\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion-A\"\u003e\n\u003cp\u003eYes, the aluminum cell housing is threaded on both sides. This allows you to screw another filter, like a color planetary filter, directly into it. For example, you could stack it with a #21 Orange filter to enhance detail in Mars's dust storms while also taming its brightness at opposition.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion\"\u003e\n\u003ch3 class=\"DAV-accordion-Q\"\u003eDoes this filter work for solar observing?\u003c\/h3\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion-A\"\u003e\n\u003cp\u003e\u003cstrong\u003eNEVER.\u003c\/strong\u003e This filter is absolutely not safe for solar observing and must never be used to look at the Sun. It does not block the harmful infrared (IR) or ultraviolet (UV) radiation that causes instant and permanent eye damage. Safe solar observing requires a dedicated, full-aperture solar filter designed specifically for that purpose.\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\u003eSize Diameter\u003c\/td\u003e\n\u003ctd\u003e31.75mm (1.25\")\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eLight Transmission\u003c\/td\u003e\n\u003ctd\u003e13%\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eFilter Type\u003c\/td\u003e\n\u003ctd\u003eNeutral Density\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eCell Housing\u003c\/td\u003e\n\u003ctd\u003eAluminum\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eStackable\u003c\/td\u003e\n\u003ctd\u003eYes\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eFilter Dimensions\u003c\/td\u003e\n\u003ctd\u003e31mm x 11.5mm (1.22\" x .45\")\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eFilter Weight\u003c\/td\u003e\n\u003ctd\u003e0.21 oz (6 g)\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eCase Dimensions\u003c\/td\u003e\n\u003ctd\u003e54.5mm x 43mm x 18mm (2.14\" x 1.7\" x .7\")\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eCase Weight\u003c\/td\u003e\n\u003ctd\u003e0.5 oz (14 g)\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eTotal Package Weight\u003c\/td\u003e\n\u003ctd\u003e0.88 oz (25 g)\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\"\u003eNeutral Density Moon Filter - 1.25\"\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\"\u003eProtective Plastic Case\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\u003ca href=\"https:\/\/davidastro.com\/pages\/celestron-warranty-policy\" rel=\"noopener\" target=\"_blank\"\u003eCelestron 2-Year Warranty\u003c\/a\u003e\u003c\/li\u003e\n\u003c\/ul\u003e","brand":"Celestron","offers":[{"title":"Default Title","offer_id":44967149568285,"sku":"CEL-94105","price":28.0,"currency_code":"CAD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0753\/5280\/1565\/products\/Celestron-Neutral-Density-Moon-Filter-1-25-inch-94105-1__04155.1594230267.1280.1280.jpg?v=1684337250"},{"product_id":"celestron-variable-polarizing-filter-1-25","title":"Celestron Variable Polarizing Filter - 1.25”","description":"\u003cul class=\"DAV-feature-list\"\u003e\n\u003cli\u003eAdjustable light transmission from 1% to 40%\u003c\/li\u003e\n\u003cli\u003eStandard 1.25” filter format fits most eyepieces\u003c\/li\u003e\n\u003cli\u003eReduces brightness without altering an object's natural color\u003c\/li\u003e\n\u003cli\u003eEnhances detail on the Moon and planets\u003c\/li\u003e\n\u003cli\u003eDurable and lightweight aluminum cell housing\u003c\/li\u003e\n\u003cli\u003eStackable design allows use with other filters\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\u003eCelestron Variable Polarizing Filter - 1.25”\u003c\/h2\u003e\n\u003cp\u003eThe Celestron Variable Polarizing Filter for 1.25” eyepieces gives you precise control over image brightness, with an adjustable light transmission ranging from a dim 1% to a moderate 40%. Weighing just 0.56 oz (16 g), this filter dials in the perfect view of bright celestial objects by simply rotating the aluminum cell housing. Unlike fixed-transmission moon filters, this variable design allows you to adapt to changing seeing conditions or target altitudes in real-time.\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\u003eAdjustable Light Control: From 1% to 40% Transmission\u003c\/h3\u003e\n\u003cp\u003eThe core of this filter is its ability to act as a dimmer switch for your telescope. By rotating the lower ring of the two-piece filter, you can smoothly adjust the amount of light reaching your eye from 40% all the way down to just 1%. This is a significant advantage over single-transmission neutral density or moon filters, which often make the view too dark or not dark enough.\u003c\/p\u003e\n\u003cp\u003eThis level of control is essential for observing the Moon, where the ideal brightness changes dramatically with its phase. A full Moon requires maximum dimming to reduce glare and see fine rille and crater detail, while a thin crescent may only need a slight reduction in brightness. This filter adapts to any scenario without requiring you to swap out accessories.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-bg-light\"\u003e\n\u003cdiv class=\"DAV-section\"\u003e\n\u003ch3\u003eLunar and Daytime Planetary Observing: Enhanced Contrast Without Color Shift\u003c\/h3\u003e\n\u003cp\u003eThe Celestron Variable Polarizing Filter reduces brightness without altering the true color of the celestial object, a critical feature for both visual observers and astro-imagers. When viewing the Moon, this neutral filtration cuts through the overwhelming glare, allowing subtle details along the terminator to become clearly defined. For imagers, it prevents bright lunar highlands from being overexposed, preserving data in your final image.\u003c\/p\u003e\n\u003cp\u003eThis filter also excels at daytime astronomy. It can be used to darken the bright blue sky, dramatically increasing the contrast of Venus or Jupiter against the background. This makes it possible to locate and observe planets long before sunset, extending your available viewing time.\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\u003eSmart Design: Stackable 1.25” Aluminum Cell\u003c\/h3\u003e\n\u003cp\u003eBuilt with a lightweight yet durable aluminum cell housing, the filter adds only 0.56 oz (16 g) to your eyepiece, ensuring it won't create balance issues on your telescope. The standard 31.75mm (1.25\") filter threads are compatible with virtually all 1.25\" eyepieces and many accessories.\u003c\/p\u003e\n\u003cp\u003eFor advanced applications, the filter is stackable. Both sides of the housing are threaded, allowing you to attach additional filters, such as a color filter to bring out specific details on a planet's surface while simultaneously controlling its brightness. This adds another layer of utility, letting you create custom filter combinations for specific targets.\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\"\u003eWhy use the Celestron Variable Polarizing Filter instead of a standard Moon filter?\u003c\/h3\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion-A\"\u003e\n\u003cp\u003eA standard Moon filter has a fixed light transmission (typically 13% or 25%). The Celestron Variable Polarizing Filter allows you to adjust the brightness from \u003cstrong\u003e1% to 40%\u003c\/strong\u003e. This means you can dial in the perfect brightness for any lunar phase, telescope aperture, or seeing condition, which is impossible with a fixed filter.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion\"\u003e\n\u003ch3 class=\"DAV-accordion-Q\"\u003eWill this 1.25” filter change the color of planets like Jupiter or Mars?\u003c\/h3\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion-A\"\u003e\n\u003cp\u003eNo, it will not. The filter is designed to be color-neutral, reducing brightness across the visual spectrum evenly. This means Jupiter's cloud bands and Mars' polar caps will retain their natural colors, just at a more comfortable brightness level.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion\"\u003e\n\u003ch3 class=\"DAV-accordion-Q\"\u003eHow does the Celestron Variable Polarizing Filter help with viewing Venus during the day?\u003c\/h3\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion-A\"\u003e\n\u003cp\u003eDaytime viewing is a challenge because the planet is faint against a bright blue sky. This filter darkens the sky background significantly, which increases the contrast and makes the planet \"pop\" into view. It allows you to find and observe planets that would otherwise be lost in the glare.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion\"\u003e\n\u003ch3 class=\"DAV-accordion-Q\"\u003eCan I stack this filter with other 1.25\" filters?\u003c\/h3\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion-A\"\u003e\n\u003cp\u003eYes. The aluminum cell is threaded on both sides, making it fully stackable. You can, for example, thread it onto a #80A Blue filter to enhance details on Jupiter while also using the polarizing feature to reduce its overall brightness for more comfortable viewing.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion\"\u003e\n\u003ch3 class=\"DAV-accordion-Q\"\u003eIs the Celestron Variable Polarizing Filter difficult to adjust while on the eyepiece?\u003c\/h3\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion-A\"\u003e\n\u003cp\u003eNo, it's designed for easy use at the telescope. Once threaded onto your 1.25\" eyepiece, you simply grip and rotate the bottom section of the filter housing. This smooth rotation changes the polarization angle, dimming or brightening the view without needing to remove the eyepiece.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion\"\u003e\n\u003ch3 class=\"DAV-accordion-Q\"\u003eIs this filter useful for deep-sky objects?\u003c\/h3\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion-A\"\u003e\n\u003cp\u003eGenerally, no. Deep-sky objects like galaxies and nebulae are extremely faint, and the goal is to gather as much light as possible. This filter is designed to reduce the light from very bright objects like the Moon, planets, and double stars. Using it on a faint nebula would make it invisible.\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\u003eSize Diameter\u003c\/td\u003e\n\u003ctd\u003e31.75mm (1.25\")\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eLight Transmission\u003c\/td\u003e\n\u003ctd\u003eAdjustable (1% to 40%)\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eCell Housing\u003c\/td\u003e\n\u003ctd\u003eAluminum\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eStackable\u003c\/td\u003e\n\u003ctd\u003eYes, threaded on both sides\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eFilter Dimensions\u003c\/td\u003e\n\u003ctd\u003e31.4mm x 22.4mm (1.23\" x .88\")\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eFilter Weight\u003c\/td\u003e\n\u003ctd\u003e0.56 oz (16 g)\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eCase Dimensions\u003c\/td\u003e\n\u003ctd\u003e68mm x 28mm (2.67\" x 1.1\")\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eCase Weight\u003c\/td\u003e\n\u003ctd\u003e0.91 oz (26 g)\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eTotal Package Weight\u003c\/td\u003e\n\u003ctd\u003e1.7 oz (50 g)\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\u003cimg class=\"DAV-img-box\" alt=\"Celestron 1.25-inch Variable Polarizing Filter\" src=\"https:\/\/cdn.shopify.com\/s\/files\/1\/0753\/5280\/1565\/files\/Celestron-Variable-Polarizing-Filter-1.25-1.jpg?v=1782256863\"\u003e\n\u003cdiv\u003e\n\u003cp class=\"DAV-item-title\"\u003eVariable Polarizing Filter - 1.25”\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\u003cimg class=\"DAV-img-box\" alt=\"Plastic protective case for the filter\" src=\"https:\/\/cdn.shopify.com\/s\/files\/1\/0753\/5280\/1565\/files\/Celestron-Filter-Case-1.25-1.jpg?v=1782256863\"\u003e\n\u003cdiv\u003e\n\u003cp class=\"DAV-item-title\"\u003eFilter Case\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\n\u003cul class=\"DAV-grid\"\u003e\n\u003c\/ul\u003e\n\u003c\/li\u003e\n\u003cli\u003e\u003ca href=\"https:\/\/davidastro.com\/pages\/celestron-warranty-policy\" rel=\"noopener\" target=\"_blank\"\u003eCelestron 2-Year Warranty\u003c\/a\u003e\u003c\/li\u003e\n\u003c\/ul\u003e","brand":"Celestron","offers":[{"title":"Default Title","offer_id":44967149601053,"sku":"CEL-94107","price":60.0,"currency_code":"CAD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0753\/5280\/1565\/products\/Celestron-Variable-Polarizing-Filter-1-25-inch-94107-1__57811.1594229204.1280.1280.jpg?v=1684337258"},{"product_id":"explore-scientific-nebula-filter-cls-1-25","title":"Explore Scientific Nebula Filter CLS - 1.25\"","description":"\u003cul class=\"DAV-feature-list\"\u003e\n\u003cli\u003eCity Light Suppression (CLS) Filter\u003c\/li\u003e\n\u003cli\u003eEnhances Contrast for Deep-Sky Objects\u003c\/li\u003e\n\u003cli\u003eAvailable in 1.25\" and 2\" Sizes\u003c\/li\u003e\n\u003cli\u003eIdeal for Viewing Nebulae and Galaxies\u003c\/li\u003e\n\u003cli\u003eThreads Directly into Standard 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\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\u003eExplore Scientific Nebula Filter CLS - 1.25\" \u0026amp; 2\"\u003c\/h2\u003e\n\u003cp\u003eThe Explore Scientific Nebula Filter CLS, available in standard 1.25\" and 2\" formats, is a general-purpose light pollution filter engineered to darken the sky background and significantly increase contrast on a wide range of deep-sky objects.\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\u003eBroadband Contrast Enhancement for Urban Skies\u003c\/h3\u003e\n\u003cp\u003eThis City Light Suppression (CLS) filter works by selectively blocking common wavelengths of artificial lighting, such as sodium and mercury vapor streetlights, which are the primary cause of urban skyglow. By rejecting this unwanted light while transmitting the key wavelengths emitted by deep-sky objects, the filter provides a dramatically darker sky background. This isolates faint nebulae and galaxies from the washed-out backdrop, making them easier to detect and observe.\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 General-Purpose Filter for Nebulae and Galaxies\u003c\/h3\u003e\n\u003cp\u003eUnlike narrowband filters that target specific emission lines, the CLS is a broadband filter designed for versatility. It improves the view of all types of deep-sky objects, including emission nebulae like the Orion Nebula (M42), reflection nebulae, and even broadband targets like the Andromeda Galaxy (M31). This makes the Explore Scientific CLS an excellent first filter for an observer looking for a single, effective tool to combat light pollution across the celestial catalog.\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\"\u003eHow does the Explore Scientific CLS filter improve views from a suburban backyard?\u003c\/h3\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion-A\"\u003e\n\u003cp\u003eThe Explore Scientific CLS filter darkens the sky background by blocking the most common wavelengths of light pollution from streetlights. This increases the contrast between your target object and the sky, making faint details in nebulae and galaxies more visible, even from moderately light-polluted areas.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion\"\u003e\n\u003ch3 class=\"DAV-accordion-Q\"\u003eWhat is the difference between the Explore Scientific CLS and a UHC filter?\u003c\/h3\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion-A\"\u003e\n\u003cp\u003eA \u003cstrong\u003eCLS (City Light Suppression)\u003c\/strong\u003e filter is a broadband filter, meaning it passes a wider range of light, making it effective on galaxies and star clusters in addition to nebulae. A \u003cstrong\u003eUHC (Ultra High Contrast)\u003c\/strong\u003e filter is a narrowband filter that passes a much smaller range of light, primarily the OIII and H-beta lines from emission nebulae. A UHC provides higher contrast on those specific targets but is less effective for broadband sources like galaxies.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion\"\u003e\n\u003ch3 class=\"DAV-accordion-Q\"\u003eCan I use the Explore Scientific CLS filter for astrophotography?\u003c\/h3\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion-A\"\u003e\n\u003cp\u003eYes, the CLS filter is a popular choice for beginner to intermediate astrophotographers using color cameras (DSLR, Mirrorless, or One-Shot-Color astro cameras). It helps capture better data from light-polluted locations by reducing skyglow, leading to improved contrast and color balance in the final image.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion\"\u003e\n\u003ch3 class=\"DAV-accordion-Q\"\u003eWill the Explore Scientific CLS filter help me see the Orion Nebula (M42) with my 8\" Dobsonian?\u003c\/h3\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion-A\"\u003e\n\u003cp\u003eAbsolutely. The Orion Nebula (M42) is a bright emission nebula that responds extremely well to a CLS filter. With an 8\" telescope, the filter will darken the surrounding sky significantly, making the faint, extended wings of the nebula pop into view and revealing more structure within the bright core.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion\"\u003e\n\u003ch3 class=\"DAV-accordion-Q\"\u003eHow will the Explore Scientific CLS filter affect views of the Andromeda Galaxy (M31)?\u003c\/h3\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion-A\"\u003e\n\u003cp\u003eThe Andromeda Galaxy (M31) is a broadband target, meaning it emits light across the entire visible spectrum. The Explore Scientific CLS filter will help by dimming the skyglow around the galaxy, which can make its faint outer arms easier to trace. While it will slightly dim the galaxy itself, the contrast enhancement often results in a more detailed overall view, especially of the dust lanes near the core.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion\"\u003e\n\u003ch3 class=\"DAV-accordion-Q\"\u003eDoes the Explore Scientific CLS filter thread into all standard 1.25\" and 2\" eyepieces?\u003c\/h3\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion-A\"\u003e\n\u003cp\u003eYes. Both the 1.25\" and 2\" versions of the Explore Scientific CLS filter feature standard filter threads. They are designed to screw directly into the barrel of any corresponding 1.25\" or 2\" eyepiece or accessory, such as a filter wheel or camera nosepiece.\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\u003eGTIN\u003c\/td\u003e\n\u003ctd\u003e812257017195\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eAvailable Sizes\u003c\/td\u003e\n\u003ctd\u003e1.25\", 2\"\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\u003c\/ul\u003e\n\u003c\/li\u003e\n\u003cli\u003e\n\u003ca href=\"https:\/\/davidastro.com\/pages\/explore-scientific-warranty-policy\" rel=\"noopener\" target=\"_blank\"\u003eExplore Scientific Warranty\u003c\/a\u003e\n\u003c\/li\u003e\n\u003c\/ul\u003e","brand":"Explore Scientific","offers":[{"title":"1.25\"","offer_id":44967202554141,"sku":"ES-310225","price":153.99,"currency_code":"CAD","in_stock":true},{"title":"2\"","offer_id":44967202586909,"sku":"ES-310220-1","price":168.0,"currency_code":"CAD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0753\/5280\/1565\/products\/Explore-Scientific-Nebula-Filter-CLS-1-25-inch-310225-1__83920.1594240362.1280.1280.jpg?v=1684338886"},{"product_id":"explore-scientific-nebula-filter-h-beta-2-0","title":"Explore Scientific Nebula Filter H-Beta - 2.0\"","description":"\u003cul class=\"DAV-feature-list\"\u003e\n\u003cli\u003e2.0-inch Barrel Size\u003c\/li\u003e\n\u003cli\u003eIsolates Hydrogen-Beta (H-Beta) Emission Line\u003c\/li\u003e\n\u003cli\u003eDramatically Increases Contrast on Specific Nebulae\u003c\/li\u003e\n\u003cli\u003eBlocks Artificial Light Pollution\u003c\/li\u003e\n\u003cli\u003eStandard M48x0.75 Filter Threads\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\u003eExplore Scientific Nebula Filter H-Beta - 2.0\"\u003c\/h2\u003e\n\u003cp\u003eThe Explore Scientific Nebula Filter H-Beta - 2.0\" is a specialized line filter designed to fit standard 2.0-inch eyepieces and filter wheels, isolating the faint hydrogen-beta emission line to reveal specific nebulae that are otherwise nearly invisible against a light-polluted sky.\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 2.0-inch Filter for Hydrogen-Beta Emission\u003c\/h3\u003e\n\u003cp\u003eThis filter operates by blocking all wavelengths of light except for the narrow band corresponding to the hydrogen-beta emission line. This extreme selectivity darkens the sky background, effectively eliminating the glow from most forms of artificial lighting and allowing the faint structural details of specific nebulae to stand out with striking contrast.\u003c\/p\u003e\n\u003cp\u003eThe 2.0-inch format is critical for this filter's intended targets, which are often large and diffuse. Paired with a low-power, wide-field 2.0-inch eyepiece, you can frame these expansive objects in their entirety while gathering the maximum amount of light from your telescope's aperture.\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\u003eUnveiling \"Invisible\" Nebulae: The Horsehead and California Nebula\u003c\/h3\u003e\n\u003cp\u003eWhile many filters enhance a wide range of objects, the H-Beta filter is a specialist's tool for a select list of targets that are notoriously difficult to observe. Its primary purpose is to make the impossible, possible. For visual observers, this filter is often the only way to glimpse faint nebulae that are rich in H-beta emissions.\u003c\/p\u003e\n\u003cul\u003e\n\u003cli\u003e\n\u003cstrong\u003eHorsehead Nebula (Barnard 33):\u003c\/strong\u003e This iconic dark nebula is nearly impossible to see visually without an H-Beta filter to enhance the faint glowing hydrogen gas (IC 434) behind it.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eCalifornia Nebula (NGC 1499):\u003c\/strong\u003e A large, faint emission nebula in Perseus that glows almost exclusively in H-alpha and H-beta light. The H-Beta filter provides a dramatic contrast boost, making its shape discernible.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eCocoon Nebula (IC 5146):\u003c\/strong\u003e Another challenging target where the H-Beta filter can help pull the faint nebulosity from the background sky.\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\u003eH-Beta vs. O-III: A Specialized Filter for Key Targets\u003c\/h3\u003e\n\u003cp\u003eAn Oxygen-III (O-III) or Ultra-High Contrast (UHC) filter is typically a better first choice for a general-purpose nebula filter, as it enhances a much broader range of objects, including planetary nebulae and the Orion Nebula (M42). The H-Beta filter is not intended to replace these.\u003c\/p\u003e\n\u003cp\u003eInstead, it complements them by excelling where they fall short. For the specific targets that emit strongly in the H-beta line, this filter provides a view that no other filter can match. It is an essential addition for the dedicated deep-sky observer looking to complete their \"life list\" of challenging celestial objects.\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\"\u003eWill the Explore Scientific H-Beta 2.0\" filter help me see the Horsehead Nebula (Barnard 33) with my 10-inch Dobsonian?\u003c\/h3\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion-A\"\u003e\n\u003cp\u003eYes, absolutely. For a visual observation of the Horsehead Nebula, an H-Beta filter is considered essential. In a 10-inch telescope under dark skies, this 2.0\" filter will significantly increase the contrast of the glowing IC 434 nebula behind the dark Horsehead silhouette, giving you the best possible chance to detect it.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion\"\u003e\n\u003ch3 class=\"DAV-accordion-Q\"\u003eIs the 2.0\" H-Beta filter a good choice for imaging the California Nebula (NGC 1499)?\u003c\/h3\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion-A\"\u003e\n\u003cp\u003eWhile this filter can be used for imaging, H-Beta is a much weaker signal than Hydrogen-Alpha (H-alpha). For monochrome astrophotography, an H-alpha filter will produce superior results on the California Nebula. However, for color imaging (especially with one-shot color cameras), adding data through an H-Beta filter can help capture a more accurate color balance in the blue channel for this specific object.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion\"\u003e\n\u003ch3 class=\"DAV-accordion-Q\"\u003eWhy do I need an H-Beta filter if I already have a UHC or O-III filter?\u003c\/h3\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion-A\"\u003e\n\u003cp\u003eUHC and O-III filters are excellent for the vast majority of emission and planetary nebulae. However, they do not pass the H-beta line with the same efficiency. For a small but famous list of objects like the Horsehead Nebula and California Nebula, the H-Beta filter provides a significantly better view, often making the difference between seeing the object and not seeing it at all.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion\"\u003e\n\u003ch3 class=\"DAV-accordion-Q\"\u003eWhat makes the Explore Scientific H-Beta filter effective against light pollution?\u003c\/h3\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion-A\"\u003e\n\u003cp\u003eThis filter works by isolating a very narrow portion of the light spectrum where the nebula's light is concentrated. It blocks most other wavelengths, including the common sources of light pollution like sodium and mercury vapor streetlights. This darkens the sky background, making the faint light of the nebula appear much brighter in comparison.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion\"\u003e\n\u003ch3 class=\"DAV-accordion-Q\"\u003eWill this 2.0\" H-Beta filter work with my specific brand of eyepieces?\u003c\/h3\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion-A\"\u003e\n\u003cp\u003eYes. The Explore Scientific H-Beta filter is built in a standard 2.0-inch cell with M48x0.75 threads. This is the industry standard for 2.0\" astronomy filters and will thread into any 2.0\" eyepiece or filter wheel that has standard filter threads.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion\"\u003e\n\u003ch3 class=\"DAV-accordion-Q\"\u003eIs the H-Beta filter useful for any objects besides the Horsehead and California Nebulae?\u003c\/h3\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion-A\"\u003e\n\u003cp\u003eWhile those are its primary targets, the H-Beta filter can also offer subtle enhancements on other objects. Some observers report it helps with the faint outer loops of the Veil Nebula complex in Cygnus and can bring out detail in the Flame Nebula (NGC 2024) near Alnitak. It is always worth experimenting with on various hydrogen-rich regions.\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 Size\u003c\/td\u003e\n\u003ctd\u003e2.0\"\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003ePrimary Emission Line\u003c\/td\u003e\n\u003ctd\u003eHydrogen-Beta (H-Beta)\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eThreads\u003c\/td\u003e\n\u003ctd\u003eM48x0.75\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eGTIN\u003c\/td\u003e\n\u003ctd\u003e812257017232\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\"\u003eExplore Scientific Nebula Filter H-Beta - 2.0\"\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\"\u003eProtective Case\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\n\u003cul class=\"DAV-grid\"\u003e\n\u003c\/ul\u003e\n\u003c\/li\u003e\n\u003cli\u003e\n\u003ca href=\"https:\/\/davidastro.com\/pages\/explore-scientific-warranty-policy\" rel=\"noopener\" target=\"_blank\"\u003eExplore Scientific Warranty\u003c\/a\u003e\n\u003c\/li\u003e\n\u003c\/ul\u003e","brand":"Explore Scientific","offers":[{"title":"Default Title","offer_id":44967202783517,"sku":"ES-310230","price":251.99,"currency_code":"CAD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0753\/5280\/1565\/products\/Explore-Scientific-Nebula-Filter-H-Beta-2-0-inch-310230-1__02827.1594240363.1280.1280.jpg?v=1684338905"},{"product_id":"explore-scientific-neutral-density-filter-nd-0-9-1-25","title":"Explore Scientific Neutral Density Filter ND 0.9 - 1.25\"","description":"\u003cul class=\"DAV-feature-list\"\u003e\n\u003cli\u003eND 0.9 Optical Density\u003c\/li\u003e\n\u003cli\u003e1.25\" Barrel Diameter\u003c\/li\u003e\n\u003cli\u003eReduces Glare for Lunar Observing\u003c\/li\u003e\n\u003cli\u003eAids in Splitting Unequal Double Stars\u003c\/li\u003e\n\u003cli\u003eUniform Light Transmission Across the Spectrum\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\u003eExplore Scientific Neutral Density Filter ND 0.9 - 1.25\"\u003c\/h2\u003e\n\u003cp\u003eThe Explore Scientific Neutral Density Filter ND 0.9 in a 1.25\" format is engineered to reduce overwhelming brightness from celestial objects without altering their natural color. This ND 0.9 filter, also referred to as an ND96, is essential for reducing glare and irradiation when observing the Moon, especially in telescopes with an aperture of 4\" (10.2cm) or larger.\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\u003eTaming Lunar Glare with ND 0.9 Density in 4\"+ Telescopes\u003c\/h3\u003e\n\u003cp\u003eObserving the Moon, particularly from the first quarter to full phase, can be uncomfortably bright through a telescope, causing your pupil to contract and washing out subtle surface details. The Explore Scientific ND 0.9 filter transmits light uniformly across the spectrum, dimming the view to a comfortable level. This reduction in brightness allows you to see finer details in crater walls, rilles, and maria without being overwhelmed by glare.\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\u003eSplitting Unequal Double Stars with the ND 0.9 Filter\u003c\/h3\u003e\n\u003cp\u003eBeyond the Moon, this filter is a valuable tool for a more advanced observational challenge: splitting close double stars with a large magnitude difference. When one star in a binary pair significantly outshines its companion, its glare can completely hide the fainter star. The ND 0.9 filter dims the entire field, reducing the overpowering light from the primary star enough for the dimmer companion to become visible at the eyepiece.\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 does \"ND 0.9\" mean for the Explore Scientific filter?\u003c\/h3\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion-A\"\u003e\n\u003cp\u003e\u003cstrong\u003eND 0.9\u003c\/strong\u003e refers to the filter's optical density. This is a logarithmic scale, and an ND 0.9 filter transmits approximately 12.5% of the light that enters it, blocking the other 87.5%. This is a significant but not total reduction, making it a great general-purpose \"moon filter\" for a wide range of telescopes.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion\"\u003e\n\u003ch3 class=\"DAV-accordion-Q\"\u003eWill the Explore Scientific ND 0.9 filter help for viewing planets like Jupiter or Saturn?\u003c\/h3\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion-A\"\u003e\n\u003cp\u003eGenerally, a neutral density filter is not recommended for planetary viewing. While planets can be bright, an ND filter will dim them without enhancing any specific features. For planets, you are better served by color filters (like a light blue #80A or green #58) which can increase the contrast of specific atmospheric details like Jupiter's cloud bands or Mars' polar caps.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion\"\u003e\n\u003ch3 class=\"DAV-accordion-Q\"\u003eWill the Explore Scientific ND 0.9 filter improve views of the full Moon in my 8\" f\/6 Dobsonian?\u003c\/h3\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion-A\"\u003e\n\u003cp\u003eYes, absolutely. An 8\" telescope gathers a large amount of light, and a full Moon will be dazzlingly bright. The ND 0.9 filter is an excellent match for this aperture, cutting the glare to a comfortable level. This will relieve eye strain and allow you to resolve much finer details along the terminator and within bright ray craters like Tycho and Copernicus.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion\"\u003e\n\u003ch3 class=\"DAV-accordion-Q\"\u003eI'm trying to split the double star Antares with my 4\" refractor. Will this ND 0.9 filter help?\u003c\/h3\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion-A\"\u003e\n\u003cp\u003eIt can. Antares (Alpha Scorpii) is a classic example of an unequal double, with a bright red primary and a much fainter secondary companion. A 4\" telescope has the resolution to split them, but the glare from the primary is often the problem. The ND 0.9 filter will reduce that glare, giving you a better chance to spot the faint companion, Antares B, nestled close to the primary star.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion\"\u003e\n\u003ch3 class=\"DAV-accordion-Q\"\u003eDoes the Explore Scientific ND 0.9 filter change the color of the Moon?\u003c\/h3\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion-A\"\u003e\n\u003cp\u003eNo, it does not. The \"Neutral\" in Neutral Density means it is designed to reduce the intensity of all wavelengths of light equally. This ensures that the view is simply dimmer, but the natural grey and white tones of the lunar surface are preserved without introducing a color cast.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion\"\u003e\n\u003ch3 class=\"DAV-accordion-Q\"\u003eCan I stack the Explore Scientific ND 0.9 filter with other 1.25\" filters?\u003c\/h3\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion-A\"\u003e\n\u003cp\u003eYes. The filter has standard 1.25\" filter threads (M28.5x0.6) on both sides, allowing you to stack it with other filters. For instance, you could stack it with a color filter to see if it helps with planetary viewing, or even stack it with another ND filter for an even greater dimming effect on a very large telescope.\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\u003eSize\u003c\/td\u003e\n\u003ctd\u003e1.25\"\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eOptical Density\u003c\/td\u003e\n\u003ctd\u003eND 0.9\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eRecommended Aperture\u003c\/td\u003e\n\u003ctd\u003e4\" (10.2cm) and larger\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eGTIN\u003c\/td\u003e\n\u003ctd\u003e812257017201\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\"\u003eExplore Scientific Neutral Density Filter ND 0.9 - 1.25\"\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\"\u003eProtective Case\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\n\u003cp\u003eNo manual or software is available for this product.\u003c\/p\u003e\n\u003c\/li\u003e\n\u003cli\u003e\n\u003ca href=\"https:\/\/davidastro.com\/pages\/explore-scientific-warranty-policy\" rel=\"noopener\" target=\"_blank\"\u003eExplore Scientific Warranty\u003c\/a\u003e\n\u003c\/li\u003e\n\u003c\/ul\u003e","brand":"Explore Scientific","offers":[{"title":"Default Title","offer_id":44967202816285,"sku":"ES-310245","price":69.99,"currency_code":"CAD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0753\/5280\/1565\/products\/Explore-Scientific-Neutral-Density-Filter-1-25-inch-ND-0-9-310245-1__86920.1594240363.1280.1280.jpg?v=1684338909"},{"product_id":"william-optics-stc-astro-duo-narrowband-filter","title":"William Optics STC Astro Duo-Narrowband Filter","description":"\u003cul class=\"DAV-feature-list\"\u003e\n\u003cli\u003eDual-Bandpass for H-Alpha and Oxygen-III\u003c\/li\u003e\n\u003cli\u003eSuppresses Urban Light Pollution\u003c\/li\u003e\n\u003cli\u003eIon Beam-Assisted Deposition (IBAD) Coatings\u003c\/li\u003e\n\u003cli\u003eHigh Durability and Easy-to-Clean Optical Surfaces\u003c\/li\u003e\n\u003cli\u003eMatte Black Anodized, Teflon-Coated Anti-Flare Frame\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\u003eWilliam Optics STC Astro Duo-Narrowband Filter\u003c\/h2\u003e\n\u003cp\u003eThe William Optics STC Astro Duo-Narrowband Filter is engineered to isolate the two most important emission lines for nebula photography, Hydrogen-alpha (Hα) and Oxygen-III (OIII), while aggressively blocking light pollution. By utilizing advanced Ion Beam-Assisted Deposition (IBAD) coatings, this filter delivers exceptional signal-to-noise ratio and maintains spectral stability through changing temperatures, ensuring consistent results from your light-polluted backyard.\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 Duo-Narrowband Advantage: Isolating Hα and OIII Emission Lines\u003c\/h3\u003e\n\u003cp\u003eUnlike broadband filters that pass a wide swath of the spectrum, the STC Astro Duo-Narrowband Filter targets the specific wavelengths emitted by planetary and emission nebulae. This selective transmission dramatically increases contrast by rejecting sodium and mercury vapor light from city streetlights, as well as natural skyglow, darkening the background and making faint nebulosity stand out.\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\u003eIBAD Coatings: Durability and Spectral Stability\u003c\/h3\u003e\n\u003cp\u003eThe filter employs Ion Beam-Assisted Deposition (IBAD) coating technology, which creates an extremely dense, hard, and moisture-resistant optical surface. This process ensures the filter's bandpass characteristics will not shift due to changes in temperature or humidity during an imaging session—a critical factor for maintaining consistent color balance and data quality. The robust coatings also make the filter surface easier to clean without risk of damage.\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\u003eEngineered Frame: Anti-Reflection and Easy Handling\u003c\/h3\u003e\n\u003cp\u003eEvery component is designed to minimize artifacts. The filter's frame is constructed from matte black anodized aluminum to absorb stray light and prevent internal reflections that can cause halos around bright stars. A Teflon coating on the frame's edge ensures smooth installation and removal from a filter wheel or camera nosepiece, reducing the risk of binding or cross-threading.\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\u003eDuo-Narrowband vs. Broadband LPR Filters: A Sharper Cut\u003c\/h3\u003e\n\u003cp\u003eWhile a standard Light Pollution Reduction (LPR) filter offers a modest improvement from the city, a duo-narrowband design like the STC represents a significant step up for imaging emission nebulae. Where a broadband LPR filter might pass a wide range of blue and red light, the STC filter's tight focus on just the Hα and OIII lines provides a much darker sky background. This makes it the superior choice for objects like the Orion Nebula (M42) or the Lagoon Nebula (M8), though less ideal for broadband targets like galaxies and reflection nebulae which emit light across the entire spectrum.\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 advantage of the William Optics STC Astro Duo-Narrowband Filter?\u003c\/h3\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion-A\"\u003e\n\u003cp\u003eIts primary advantage is isolating the key \u003cstrong\u003eH-alpha\u003c\/strong\u003e and \u003cstrong\u003eOIII\u003c\/strong\u003e wavelengths emitted by most nebulae. This allows you to capture high-contrast images from light-polluted urban and suburban locations by rejecting the specific wavelengths associated with artificial lighting.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion\"\u003e\n\u003ch3 class=\"DAV-accordion-Q\"\u003eHow will the STC Duo-Narrowband Filter perform on the Orion Nebula (M42) from a city?\u003c\/h3\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion-A\"\u003e\n\u003cp\u003eIt will perform exceptionally well. The Orion Nebula (M42) is rich in both Hydrogen-alpha and Oxygen-III emissions. The William Optics STC Astro Duo-Narrowband Filter will darken the light-polluted sky background, dramatically increasing the contrast and revealing faint, extended structures in the nebula that would otherwise be invisible from a city.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion\"\u003e\n\u003ch3 class=\"DAV-accordion-Q\"\u003eIs the STC Duo-Narrowband Filter suitable for imaging galaxies like Andromeda (M31)?\u003c\/h3\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion-A\"\u003e\n\u003cp\u003eNo, this is not the ideal filter for broadband targets like galaxies. Galaxies and reflection nebulae shine by reflecting starlight across the entire visible spectrum. Because the \u003cstrong\u003eWilliam Optics STC Astro Duo-Narrowband Filter\u003c\/strong\u003e blocks most of that spectrum, it will significantly dim the galaxy and produce poor results. A broadband LPR filter or unfiltered imaging from a dark site is better for galaxies.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion\"\u003e\n\u003ch3 class=\"DAV-accordion-Q\"\u003eHow does the IBAD coating on the STC Duo-Narrowband Filter improve my images?\u003c\/h3\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion-A\"\u003e\n\u003cp\u003eThe \u003cstrong\u003eIon Beam-Assisted Deposition (IBAD)\u003c\/strong\u003e process creates a very stable coating. This prevents the filter's transmission bands from shifting with temperature or humidity changes throughout the night. This stability ensures you get consistent color data and performance from dusk till dawn, a crucial factor for long-exposure astrophotography.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion\"\u003e\n\u003ch3 class=\"DAV-accordion-Q\"\u003eWhat makes the frame of the STC Duo-Narrowband Filter special?\u003c\/h3\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion-A\"\u003e\n\u003cp\u003eThe frame is designed to enhance image quality and usability. It features:\u003c\/p\u003e\n\u003cul\u003e\n\u003cli\u003e\n\u003cstrong\u003eMatte Black Anodizing:\u003c\/strong\u003e Absorbs stray light to prevent internal reflections and halos.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eTeflon Coating:\u003c\/strong\u003e Allows for smooth, easy installation and removal from your imaging train without jamming.\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion\"\u003e\n\u003ch3 class=\"DAV-accordion-Q\"\u003eCan I use the William Optics STC Duo-Narrowband Filter for visual observing?\u003c\/h3\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion-A\"\u003e\n\u003cp\u003eWhile technically possible, it is not recommended. Narrowband filters like this one block a tremendous amount of light, and the resulting image through an eyepiece would be extremely dim. These filters are designed specifically for the long exposures used in astrophotography with one-shot-color or monochrome cameras.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003c\/li\u003e\n\u003cli\u003e\n\u003ctable class=\"DAV-specifications\"\u003e\n\u003ctbody\u003e\n\u003c\/tbody\u003e\n\u003c\/table\u003e\n\u003c\/li\u003e\n\u003cli\u003e\n\u003cul class=\"DAV-grid\"\u003e\n\u003c\/ul\u003e\n\u003c\/li\u003e\n\u003cli\u003e\n\u003cul class=\"DAV-grid\"\u003e\n\u003c\/ul\u003e\n\u003c\/li\u003e\n\u003cli\u003e\n\u003ca href=\"https:\/\/davidastro.com\/pages\/william-optics-warranty-policy\" rel=\"noopener\" target=\"_blank\"\u003eWilliam Optics 2-Year Warranty\u003c\/a\u003e\n\u003c\/li\u003e\n\u003c\/ul\u003e","brand":"William Optics","offers":[{"title":"Default Title","offer_id":44967225590045,"sku":"WO-YF-STC-ADN","price":660.0,"currency_code":"CAD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0753\/5280\/1565\/products\/William-Optics-STC-Astro-Duo-Narrowband-Filter-YF-STC-ADN-1__15183.1596133266.1280.1280.jpg?v=1684339179"},{"product_id":"william-optics-stc-ultra-layer-astro-multispectra-filter-48mm","title":"William Optics STC Ultra Layer Astro Multispectra Filter - 48mm","description":"\u003cul class=\"DAV-feature-list\"\u003e\n\u003cli\u003e48mm (M48) Filter Size\u003c\/li\u003e\n\u003cli\u003eMulti-Bandpass Light Pollution Suppression\u003c\/li\u003e\n\u003cli\u003ePasses H-α, H-β, and OIII Emission Lines\u003c\/li\u003e\n\u003cli\u003eSchott B270 Optical Glass Substrate\u003c\/li\u003e\n\u003cli\u003eSTC Ultra-Layer IBAD Anti-Reflection Coatings\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\u003eWilliam Optics STC Ultra Layer Astro Multispectra Filter - 48mm\u003c\/h2\u003e\n\u003cp\u003eThe 48mm William Optics STC Ultra Layer Astro Multispectra Filter is engineered to restore natural color and contrast to astrophotography by suppressing common mercury, sodium, and LED light pollution while transmitting crucial H-alpha, H-beta, and OIII nebula lines through its coated Schott B270 optical glass.\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\u003eRestoring Natural Color from Light-Polluted Skies\u003c\/h3\u003e\n\u003cp\u003eThis filter is designed as a direct response to the challenge of urban and suburban imaging. It isolates and blocks the most common sources of artificial skyglow—specifically mercury vapor, high-pressure sodium, and certain disruptive LED frequencies—that wash out faint deep-sky objects.\u003c\/p\u003e\n\u003cp\u003eBy removing the offending wavelengths, the STC Astro Multispectra filter darkens the sky background significantly. This allows you to use longer exposures from compromised locations, revealing faint nebulosity and galactic structure while preserving a natural color balance in stars and surrounding fields.\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-Contrast Imaging of H-α, H-β, and OIII Targets\u003c\/h3\u003e\n\u003cp\u003eWhile aggressively filtering light pollution, the STC Astro Multispectra preserves the most important wavelengths for astrophotography. The filter's bandpass is tailored to transmit the deep red of Hydrogen-alpha, the teal of Oxygen-III, and the blue-green of Hydrogen-beta with high efficiency.\u003c\/p\u003e\n\u003cp\u003eThis selective transmission dramatically increases the contrast between emission nebulae and the background sky. Objects like the North American Nebula (NGC 7000) or the Orion Nebula (M42) stand out with enhanced structure and saturation, producing images with greater depth and clarity even from a backyard observatory.\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\u003eSchott B270 Glass and Ion Beam Assisted Coatings\u003c\/h3\u003e\n\u003cp\u003eThe filter's optical foundation is premium Schott B270 glass, known for its clarity and homogeneity. This ensures that the filter imparts no degradation to your imaging system's resolution. Each surface is treated with STC’s proprietary Ultra Layer coatings applied via Ion Beam Assisted Deposition (IBAD).\u003c\/p\u003e\n\u003cp\u003eThis advanced coating process results in an exceptionally hard, durable, and environmentally stable surface that resists moisture and is easier to clean. The multi-layer coatings are also optimized to minimize reflections and prevent the halos around bright stars that can plague inferior filters, ensuring maximum light transmission of the desired wavelengths.\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 kind of light pollution does the WO STC Astro Multispectra filter block?\u003c\/h3\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion-A\"\u003e\n\u003cp\u003eThe filter is designed to suppress the most common sources of urban light pollution, including \u003cstrong\u003emercury vapor lamps\u003c\/strong\u003e, \u003cstrong\u003ehigh and low-pressure sodium vapor lamps\u003c\/strong\u003e, and certain wavelengths of \u003cstrong\u003eLED lighting\u003c\/strong\u003e that cause skyglow.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion\"\u003e\n\u003ch3 class=\"DAV-accordion-Q\"\u003eIs the 48mm STC Astro Multispectra filter good for imaging galaxies like Andromeda (M31)?\u003c\/h3\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion-A\"\u003e\n\u003cp\u003eYes, it is very effective for broadband targets like galaxies. By reducing skyglow, the filter increases the contrast between the galaxy's faint outer arms and the night sky. Unlike narrowband filters, it preserves the natural star colors in the galaxy's halo and core, making it an excellent choice for imaging M31 from suburban locations.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion\"\u003e\n\u003ch3 class=\"DAV-accordion-Q\"\u003eHow does the STC Astro Multispectra filter affect star color compared to a UHC filter?\u003c\/h3\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion-A\"\u003e\n\u003cp\u003eThe STC Astro Multispectra is designed to produce more \u003cstrong\u003enatural star colors\u003c\/strong\u003e. While a traditional UHC (Ultra High Contrast) filter creates very high contrast on nebulae, it often does so at the cost of a strong blue-green color cast. This filter uses a multi-bandpass approach to let more of the stellar continuum through, resulting in a more balanced and photographically neutral image.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion\"\u003e\n\u003ch3 class=\"DAV-accordion-Q\"\u003eCan I use the STC Astro Multispectra 48mm filter with a full-frame camera?\u003c\/h3\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion-A\"\u003e\n\u003cp\u003eYes, the \u003cstrong\u003e48mm (or 2-inch) filter size\u003c\/strong\u003e is ideal for use with full-frame DSLR or dedicated astronomy cameras. The large format prevents vignetting, ensuring the sensor is evenly illuminated from corner to corner, which is critical for wide-field astrophotography and Milky Way landscapes.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion\"\u003e\n\u003ch3 class=\"DAV-accordion-Q\"\u003eWhat makes the IBAD coatings on this filter special?\u003c\/h3\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion-A\"\u003e\n\u003cp\u003e\u003cstrong\u003eIon Beam Assisted Deposition (IBAD)\u003c\/strong\u003e is an advanced coating process that creates extremely dense and durable layers on the optical surface. This makes the filter's coatings highly resistant to scratching from routine cleaning and degradation from environmental factors like humidity. It also yields superior anti-reflection performance, preventing halos and internal reflections.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion\"\u003e\n\u003ch3 class=\"DAV-accordion-Q\"\u003eIs this filter suitable for imaging large targets like the North American Nebula (NGC 7000)?\u003c\/h3\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion-A\"\u003e\n\u003cp\u003eAbsolutely. This filter is perfect for large, emission-rich targets like the North American Nebula (NGC 7000) or the Veil Nebula complex. It allows the critical \u003cstrong\u003eH-alpha and OIII\u003c\/strong\u003e light from the nebula to pass through while blocking skyglow, making it ideal for capturing these objects with wide-field refractors or camera lenses.\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\u003eAstro Multispectra Light Pollution\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eSize\u003c\/td\u003e\n\u003ctd\u003e48mm\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eThread\u003c\/td\u003e\n\u003ctd\u003eM48\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eGlass Substrate\u003c\/td\u003e\n\u003ctd\u003eSchott B270\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eCoating Technology\u003c\/td\u003e\n\u003ctd\u003eSTC Ultra Layer IBAD\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\"\u003eWilliam Optics STC Ultra Layer Astro Multispectra Filter - 48mm\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\n\u003cli\u003e\n\u003ca href=\"https:\/\/davidastro.com\/pages\/william-optics-warranty-policy\" rel=\"noopener\" target=\"_blank\"\u003eWilliam Optics 2-Year Warranty\u003c\/a\u003e\n\u003c\/li\u003e\n\u003c\/ul\u003e","brand":"William Optics","offers":[{"title":"Default Title","offer_id":44967226573085,"sku":"WO-YF-STC-M48","price":328.0,"currency_code":"CAD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0753\/5280\/1565\/products\/William-Optics-STC-Ultra-Layer-Astro-Multispectra-Filter-48mm-YF-STC-M48-1__78203.1596133266.1280.1280.jpg?v=1684339482"},{"product_id":"chroma-h-alpha-filter-3nm","title":"Chroma H-alpha Filter - 3nm","description":"\u003c!-- more --\u003e\u003cp\u003eH-alpha filters are essential for imaging nebulae and other objects which are rich in ionized hydrogen. At 656.3nm, a narrow-band emission filter is required to separate H-alpha from the SII doublet (671.6nm and 673.1nm).\u003c\/p\u003e\u003cul\u003e\n\u003cli\u003eFilters designed for use with CCD and for f\/4.0 or slower\u003c\/li\u003e\n\u003cli\u003eNo reflections leading to image distortions or \"back reflections\"\u003c\/li\u003e\n\u003cli\u003eTransmitted wavefront better than 0.25 waves\/inch\u003c\/li\u003e\n\u003cli\u003eDurable sputter coatings\u003c\/li\u003e\n\u003cli\u003eParallelism: \u0026lt; 30 arcsec\u003c\/li\u003e\n\u003cli\u003eThickness: 3.0 +\/-0.05mm\u003c\/li\u003e\n\u003cli\u003eExtremely durable coatings withstand humidity changes and extreme temperature fluxes and remain spectrally accurate\u003c\/li\u003e\n\u003cli\u003ein CWL and band pass adherence\u003c\/li\u003e\n\u003cli\u003eCapable of manufacturing large filters for large detectors: 50mm x 50mm, 65mm up to 76.2mm and 101.6mm square\u003c\/li\u003e\n\u003cli\u003eAll filters manufactured in Vermont\u003c\/li\u003e\n\u003c\/ul\u003e\u003cp\u003eChroma manufactures the highest quality astronomy filters with durable, sputtered hard coatings using single substrates of the best glass, eliminating the need for laminations. All primary filter coatings are applied on the front surface and anti-reflection coatings on the rear surface to prevent ghosting and to maximize transmission.\u003c\/p\u003e\u003cp\u003eHighly precise and accurate, the passbands of these filters remain spectrally stable and do not drift in response to extreme temperature fluctuations or changes in humidity. All filters may be used with apertures of f\/4 or smaller. They provide custom coating services for more demanding imaging applications requiring larger apertures such as f\/3 or f\/2. They also can provide larger sizes and unique passbands upon request.\u003c\/p\u003e","brand":"Chroma","offers":[{"title":"1.25\" Round Mounted","offer_id":44967243612445,"sku":"CT-27001-1.25M","price":805.0,"currency_code":"CAD","in_stock":true},{"title":"31mm Round Unmounted","offer_id":44967243645213,"sku":"CT-27001-31D","price":805.0,"currency_code":"CAD","in_stock":true},{"title":"36mm Round Unmounted","offer_id":44967243677981,"sku":"CT-27001-36D","price":1085.0,"currency_code":"CAD","in_stock":true},{"title":"2\" Round Mounted","offer_id":44967243710749,"sku":"CT-27001-2M","price":1820.0,"currency_code":"CAD","in_stock":true},{"title":"50mm Round Unmounted","offer_id":44967243743517,"sku":"CT-27001-50D","price":1750.0,"currency_code":"CAD","in_stock":true},{"title":"50x50mm Square Unmounted","offer_id":44967243776285,"sku":"CT-27001-50X50","price":2170.0,"currency_code":"CAD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0753\/5280\/1565\/products\/Transmission-Curve-of-Chroma-H-alpha-3nm-Filter__77186.1596071504.1280.1280.jpg?v=1684339497"},{"product_id":"chroma-h-alpha-filter-5nm","title":"Chroma H-alpha Filter - 5nm","description":"\u003c!-- more --\u003e\u003cp\u003eH-alpha filters are essential for imaging nebulae and other objects which are rich in ionized hydrogen. At 656.3nm, a narrow-band emission filter is required to separate H-alpha from the SII doublet (671.6nm and 673.1nm).\u003c\/p\u003e\u003cul\u003e\n\u003cli\u003eFilters designed for use with CCD and for f\/4.0 or slower\u003c\/li\u003e\n\u003cli\u003eNo reflections leading to image distortions or \"back reflections\"\u003c\/li\u003e\n\u003cli\u003eTransmitted wavefront better than 0.25 waves\/inch\u003c\/li\u003e\n\u003cli\u003eDurable sputter coatings\u003c\/li\u003e\n\u003cli\u003eParallelism: \u0026lt; 30 arcsec\u003c\/li\u003e\n\u003cli\u003eThickness: 3.0 +\/-0.05mm\u003c\/li\u003e\n\u003cli\u003eExtremely durable coatings withstand humidity changes and extreme temperature fluxes and remain spectrally accurate\u003c\/li\u003e\n\u003cli\u003ein CWL and band pass adherence\u003c\/li\u003e\n\u003cli\u003eCapable of manufacturing large filters for large detectors: 50mm x 50mm, 65mm up to 76.2mm and 101.6mm square\u003c\/li\u003e\n\u003cli\u003eAll filters manufactured in Vermont\u003c\/li\u003e\n\u003c\/ul\u003e\u003cp\u003eChroma manufactures the highest quality astronomy filters with durable, sputtered hard coatings using single substrates of the best glass, eliminating the need for laminations. All primary filter coatings are applied on the front surface and anti-reflection coatings on the rear surface to prevent ghosting and to maximize transmission.\u003c\/p\u003e\u003cp\u003eHighly precise and accurate, the passbands of these filters remain spectrally stable and do not drift in response to extreme temperature fluctuations or changes in humidity. All filters may be used with apertures of f\/4 or smaller. They provide custom coating services for more demanding imaging applications requiring larger apertures such as f\/3 or f\/2. They also can provide larger sizes and unique passbands upon request.\u003c\/p\u003e","brand":"Chroma","offers":[{"title":"1.25\" Round Mounted","offer_id":44967243809053,"sku":"CT-27002-1.25M","price":644.0,"currency_code":"CAD","in_stock":true},{"title":"31mm Round Unmounted","offer_id":44967243841821,"sku":"CT-27002-31D","price":644.0,"currency_code":"CAD","in_stock":true},{"title":"36mm Round Unmounted","offer_id":44967243874589,"sku":"CT-27002-36D","price":868.0,"currency_code":"CAD","in_stock":true},{"title":"2\" Round Mounted","offer_id":44967243907357,"sku":"CT-27002-2M","price":1365.0,"currency_code":"CAD","in_stock":true},{"title":"50mm Round Unmounted","offer_id":44967243940125,"sku":"CT-27002-50D","price":1295.0,"currency_code":"CAD","in_stock":true},{"title":"50x50mm Square Unmounted","offer_id":44967243972893,"sku":"CT-27002-50X50","price":1932.0,"currency_code":"CAD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0753\/5280\/1565\/products\/Transmission-Curve-of-Chroma-H-alpha-5nm-Filter__56496.1596071505.1280.1280.jpg?v=1684339501"},{"product_id":"chroma-h-alpha-filter-8nm","title":"Chroma H-alpha Filter - 8nm","description":"\u003c!-- more --\u003e\u003cp\u003eH-alpha filters are essential for imaging nebulae and other objects which are rich in ionized hydrogen. At 656.3nm, a narrow-band emission filter is required to separate H-alpha from the SII doublet (671.6nm and 673.1nm).\u003c\/p\u003e\u003cul\u003e\n\u003cli\u003eFilters designed for use with CCD and for f\/4.0 or slower\u003c\/li\u003e\n\u003cli\u003eNo reflections leading to image distortions or \"back reflections\"\u003c\/li\u003e\n\u003cli\u003eTransmitted wavefront better than 0.25 waves\/inch\u003c\/li\u003e\n\u003cli\u003eDurable sputter coatings\u003c\/li\u003e\n\u003cli\u003eParallelism: \u0026lt; 30 arcsec\u003c\/li\u003e\n\u003cli\u003eThickness: 3.0 +\/-0.05mm\u003c\/li\u003e\n\u003cli\u003eExtremely durable coatings withstand humidity changes and extreme temperature fluxes and remain spectrally accurate\u003c\/li\u003e\n\u003cli\u003ein CWL and band pass adherence\u003c\/li\u003e\n\u003cli\u003eCapable of manufacturing large filters for large detectors: 50mm x 50mm, 65mm up to 76.2mm and 101.6mm square\u003c\/li\u003e\n\u003cli\u003eAll filters manufactured in Vermont\u003c\/li\u003e\n\u003c\/ul\u003e\u003cp\u003eChroma manufactures the highest quality astronomy filters with durable, sputtered hard coatings using single substrates of the best glass, eliminating the need for laminations. All primary filter coatings are applied on the front surface and anti-reflection coatings on the rear surface to prevent ghosting and to maximize transmission.\u003c\/p\u003e\u003cp\u003eHighly precise and accurate, the passbands of these filters remain spectrally stable and do not drift in response to extreme temperature fluctuations or changes in humidity. All filters may be used with apertures of f\/4 or smaller. They provide custom coating services for more demanding imaging applications requiring larger apertures such as f\/3 or f\/2. They also can provide larger sizes and unique passbands upon request.\u003c\/p\u003e","brand":"Chroma","offers":[{"title":"1.25\" Round Mounted","offer_id":44967244038429,"sku":"CT-27003-1.25M","price":385.0,"currency_code":"CAD","in_stock":true},{"title":"31mm Round Unmounted","offer_id":44967244071197,"sku":"CT-27003-31D","price":385.0,"currency_code":"CAD","in_stock":true},{"title":"36mm Round Unmounted","offer_id":44967244103965,"sku":"CT-27003-36D","price":497.0,"currency_code":"CAD","in_stock":true},{"title":"2\" Round Mounted","offer_id":44967244136733,"sku":"CT-27003-2M","price":1162.0,"currency_code":"CAD","in_stock":true},{"title":"50mm Round Unmounted","offer_id":44967244169501,"sku":"CT-27003-50D","price":1092.0,"currency_code":"CAD","in_stock":true},{"title":"50x50mm Square Unmounted","offer_id":44967244202269,"sku":"CT-27003-50X50","price":1106.0,"currency_code":"CAD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0753\/5280\/1565\/products\/Transmission-Curve-of-Chroma-H-alpha-8nm-Filter__69220.1596071506.1280.1280.jpg?v=1684339504"},{"product_id":"chroma-h-beta-filter-3nm","title":"Chroma H-beta Filter - 3nm","description":"\u003c!-- more --\u003e\u003cp\u003eH-beta filters are also useful for imaging nebulae and objects rich in ionized hydrogen. At 486.1nm, a narrow-band filter is required to separate H-beta from nearby blue and green spectral lines. Although weaker than the H-alpha line, this is often used for visual detection as the longer red wavelengths of H-alpha are difficult to detect by eye.\u003c\/p\u003e\u003cul\u003e\n\u003cli\u003eFilters designed for use with CCD and for f\/4.0 or slower\u003c\/li\u003e\n\u003cli\u003eNo reflections leading to image distortions or \"back reflections\"\u003c\/li\u003e\n\u003cli\u003eTransmitted wavefront better than 0.25 waves\/inch\u003c\/li\u003e\n\u003cli\u003eDurable sputter coatings\u003c\/li\u003e\n\u003cli\u003eParallelism: \u0026lt; 30 arcsec\u003c\/li\u003e\n\u003cli\u003eThickness: 3.0 +\/-0.05mm\u003c\/li\u003e\n\u003cli\u003eExtremely durable coatings withstand humidity changes and extreme temperature fluxes and remain spectrally accurate\u003c\/li\u003e\n\u003cli\u003ein CWL and band pass adherence\u003c\/li\u003e\n\u003cli\u003eCapable of manufacturing large filters for large detectors: 50mm x 50mm, 65mm up to 76.2mm and 101.6mm square\u003c\/li\u003e\n\u003cli\u003eAll filters manufactured in Vermont\u003c\/li\u003e\n\u003c\/ul\u003e\u003cp\u003eChroma manufactures the highest quality astronomy filters with durable, sputtered hard coatings using single substrates of the best glass, eliminating the need for laminations. All primary filter coatings are applied on the front surface and anti-reflection coatings on the rear surface to prevent ghosting and to maximize transmission.\u003c\/p\u003e\u003cp\u003eHighly precise and accurate, the passbands of these filters remain spectrally stable and do not drift in response to extreme temperature fluctuations or changes in humidity. All filters may be used with apertures of f\/4 or smaller. They provide custom coating services for more demanding imaging applications requiring larger apertures such as f\/3 or f\/2. They also can provide larger sizes and unique passbands upon request.\u003c\/p\u003e","brand":"Chroma","offers":[{"title":"1.25\" Round Mounted","offer_id":44967244235037,"sku":"CT-27004-1.25M","price":805.0,"currency_code":"CAD","in_stock":true},{"title":"31mm Round Unmounted","offer_id":44967244267805,"sku":"CT-27004-31D","price":805.0,"currency_code":"CAD","in_stock":true},{"title":"36mm Round Unmounted","offer_id":44967244300573,"sku":"CT-27004-36D","price":1085.0,"currency_code":"CAD","in_stock":true},{"title":"2\" Round Mounted","offer_id":44967244333341,"sku":"CT-27004-2M","price":1820.0,"currency_code":"CAD","in_stock":true},{"title":"50mm Round Unmounted","offer_id":44967244366109,"sku":"CT-27004-50D","price":1750.0,"currency_code":"CAD","in_stock":true},{"title":"50x50mm Square Unmounted","offer_id":44967244398877,"sku":"CT-27004-50X50","price":2170.0,"currency_code":"CAD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0753\/5280\/1565\/products\/Transmission-Curve-of-Chroma-H-beta-3nm-Filter__82264.1596071507.1280.1280.jpg?v=1684339701"},{"product_id":"chroma-h-beta-filter-5nm","title":"Chroma H-beta Filter - 5nm","description":"\u003c!-- more --\u003e\u003cp\u003eH-beta filters are also useful for imaging nebulae and objects rich in ionized hydrogen. At 486.1nm, a narrow-band filter is required to separate H-beta from nearby blue and green spectral lines. Although weaker than the H-alpha line, this is often used for visual detection as the longer red wavelengths of H-alpha are difficult to detect by eye.\u003c\/p\u003e\u003cul\u003e\n\u003cli\u003eFilters designed for use with CCD and for f\/4.0 or slower\u003c\/li\u003e\n\u003cli\u003eNo reflections leading to image distortions or \"back reflections\"\u003c\/li\u003e\n\u003cli\u003eTransmitted wavefront better than 0.25 waves\/inch\u003c\/li\u003e\n\u003cli\u003eDurable sputter coatings\u003c\/li\u003e\n\u003cli\u003eParallelism: \u0026lt; 30 arcsec\u003c\/li\u003e\n\u003cli\u003eThickness: 3.0 +\/-0.05mm\u003c\/li\u003e\n\u003cli\u003eExtremely durable coatings withstand humidity changes and extreme temperature fluxes and remain spectrally accurate\u003c\/li\u003e\n\u003cli\u003ein CWL and band pass adherence\u003c\/li\u003e\n\u003cli\u003eCapable of manufacturing large filters for large detectors: 50mm x 50mm, 65mm up to 76.2mm and 101.6mm square\u003c\/li\u003e\n\u003cli\u003eAll filters manufactured in Vermont\u003c\/li\u003e\n\u003c\/ul\u003e\u003cp\u003eChroma manufactures the highest quality astronomy filters with durable, sputtered hard coatings using single substrates of the best glass, eliminating the need for laminations. All primary filter coatings are applied on the front surface and anti-reflection coatings on the rear surface to prevent ghosting and to maximize transmission.\u003c\/p\u003e\u003cp\u003eHighly precise and accurate, the passbands of these filters remain spectrally stable and do not drift in response to extreme temperature fluctuations or changes in humidity. All filters may be used with apertures of f\/4 or smaller. They provide custom coating services for more demanding imaging applications requiring larger apertures such as f\/3 or f\/2. 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Emission is at two lines occurring as a doublet, at 671.6 and 673.1 nm. This filter also separates sulfur emission from H-alpha emission (656.3nm).\u003c\/p\u003e\u003cul\u003e\n\u003cli\u003eFilters designed for use with CCD and for f\/4.0 or slower\u003c\/li\u003e\n\u003cli\u003eNo reflections leading to image distortions or \"back reflections\"\u003c\/li\u003e\n\u003cli\u003eTransmitted wavefront better than 0.25 waves\/inch\u003c\/li\u003e\n\u003cli\u003eDurable sputter coatings\u003c\/li\u003e\n\u003cli\u003eParallelism: \u0026lt; 30 arcsec\u003c\/li\u003e\n\u003cli\u003eThickness: 3.0 +\/-0.05mm\u003c\/li\u003e\n\u003cli\u003eExtremely durable coatings withstand humidity changes and extreme temperature fluxes and remain spectrally accurate\u003c\/li\u003e\n\u003cli\u003ein CWL and band pass adherence\u003c\/li\u003e\n\u003cli\u003eCapable of manufacturing large filters for large detectors: 50mm x 50mm, 65mm up to 76.2mm and 101.6mm square\u003c\/li\u003e\n\u003cli\u003eAll filters manufactured in Vermont\u003c\/li\u003e\n\u003c\/ul\u003e\u003cp\u003eChroma manufactures the highest quality astronomy filters with durable, sputtered hard coatings using single substrates of the best glass, eliminating the need for laminations. All primary filter coatings are applied on the front surface and anti-reflection coatings on the rear surface to prevent ghosting and to maximize transmission.\u003c\/p\u003e\u003cp\u003eHighly precise and accurate, the passbands of these filters remain spectrally stable and do not drift in response to extreme temperature fluctuations or changes in humidity. All filters may be used with apertures of f\/4 or smaller. They provide custom coating services for more demanding imaging applications requiring larger apertures such as f\/3 or f\/2. They also can provide larger sizes and unique passbands upon request.\u003c\/p\u003e","brand":"Chroma","offers":[{"title":"1.25\" Round Mounted","offer_id":44967244759325,"sku":"CT-27009-1.25M","price":805.0,"currency_code":"CAD","in_stock":true},{"title":"31mm Round Unmounted","offer_id":44967244792093,"sku":"CT-27009-31D","price":805.0,"currency_code":"CAD","in_stock":true},{"title":"36mm Round Unmounted","offer_id":44967244824861,"sku":"CT-27009-36D","price":1085.0,"currency_code":"CAD","in_stock":true},{"title":"2\" Round Mounted","offer_id":44967244857629,"sku":"CT-27009-2M","price":1820.0,"currency_code":"CAD","in_stock":true},{"title":"50mm Round Unmounted","offer_id":44967244890397,"sku":"CT-27009-50D","price":1750.0,"currency_code":"CAD","in_stock":true},{"title":"50x50mm Square Unmounted","offer_id":44967244923165,"sku":"CT-27009-50X50","price":2170.0,"currency_code":"CAD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0753\/5280\/1565\/products\/Transmission-Curve-of-Chroma-SII-3nm-Filter__16961.1596071510.1280.1280.jpg?v=1684339708"},{"product_id":"chroma-sii-filter-5nm","title":"Chroma SII Filter - 5nm","description":"\u003c!-- more --\u003e\u003cp\u003eSII filters isolate the spectral emission of singly ionized sulfur atoms, also common in nebulae. Emission is at two lines occurring as a doublet, at 671.6 and 673.1 nm. This filter also separates sulfur emission from H-alpha emission (656.3nm).\u003c\/p\u003e\u003cul\u003e\n\u003cli\u003eFilters designed for use with CCD and for f\/4.0 or slower\u003c\/li\u003e\n\u003cli\u003eNo reflections leading to image distortions or \"back reflections\"\u003c\/li\u003e\n\u003cli\u003eTransmitted wavefront better than 0.25 waves\/inch\u003c\/li\u003e\n\u003cli\u003eDurable sputter coatings\u003c\/li\u003e\n\u003cli\u003eParallelism: \u0026lt; 30 arcsec\u003c\/li\u003e\n\u003cli\u003eThickness: 3.0 +\/-0.05mm\u003c\/li\u003e\n\u003cli\u003eExtremely durable coatings withstand humidity changes and extreme temperature fluxes and remain spectrally accurate\u003c\/li\u003e\n\u003cli\u003ein CWL and band pass adherence\u003c\/li\u003e\n\u003cli\u003eCapable of manufacturing large filters for large detectors: 50mm x 50mm, 65mm up to 76.2mm and 101.6mm square\u003c\/li\u003e\n\u003cli\u003eAll filters manufactured in Vermont\u003c\/li\u003e\n\u003c\/ul\u003e\u003cp\u003eChroma manufactures the highest quality astronomy filters with durable, sputtered hard coatings using single substrates of the best glass, eliminating the need for laminations. All primary filter coatings are applied on the front surface and anti-reflection coatings on the rear surface to prevent ghosting and to maximize transmission.\u003c\/p\u003e\u003cp\u003eHighly precise and accurate, the passbands of these filters remain spectrally stable and do not drift in response to extreme temperature fluctuations or changes in humidity. All filters may be used with apertures of f\/4 or smaller. They provide custom coating services for more demanding imaging applications requiring larger apertures such as f\/3 or f\/2. 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Emission is at two lines occurring as a doublet, at 671.6 and 673.1 nm. This filter also separates sulfur emission from H-alpha emission (656.3nm).\u003c\/p\u003e\u003cul\u003e\n\u003cli\u003eFilters designed for use with CCD and for f\/4.0 or slower\u003c\/li\u003e\n\u003cli\u003eNo reflections leading to image distortions or \"back reflections\"\u003c\/li\u003e\n\u003cli\u003eTransmitted wavefront better than 0.25 waves\/inch\u003c\/li\u003e\n\u003cli\u003eDurable sputter coatings\u003c\/li\u003e\n\u003cli\u003eParallelism: \u0026lt; 30 arcsec\u003c\/li\u003e\n\u003cli\u003eThickness: 3.0 +\/-0.05mm\u003c\/li\u003e\n\u003cli\u003eExtremely durable coatings withstand humidity changes and extreme temperature fluxes and remain spectrally accurate\u003c\/li\u003e\n\u003cli\u003ein CWL and band pass adherence\u003c\/li\u003e\n\u003cli\u003eCapable of manufacturing large filters for large detectors: 50mm x 50mm, 65mm up to 76.2mm and 101.6mm square\u003c\/li\u003e\n\u003cli\u003eAll filters manufactured in Vermont\u003c\/li\u003e\n\u003c\/ul\u003e\u003cp\u003eChroma manufactures the highest quality astronomy filters with durable, sputtered hard coatings using single substrates of the best glass, eliminating the need for laminations. All primary filter coatings are applied on the front surface and anti-reflection coatings on the rear surface to prevent ghosting and to maximize transmission.\u003c\/p\u003e\u003cp\u003eHighly precise and accurate, the passbands of these filters remain spectrally stable and do not drift in response to extreme temperature fluctuations or changes in humidity. All filters may be used with apertures of f\/4 or smaller. They provide custom coating services for more demanding imaging applications requiring larger apertures such as f\/3 or f\/2. 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All primary filter coatings are applied on the front surface and anti-reflection coatings on the rear surface to prevent ghosting and to maximize transmission.\u003c\/p\u003e\u003cp\u003eHighly precise and accurate, the passbands of these filters remain spectrally stable and do not drift in response to extreme temperature fluctuations or changes in humidity. All filters may be used with apertures of f\/4 or smaller. They provide custom coating services for more demanding imaging applications requiring larger apertures such as f\/3 or f\/2. 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All primary filter coatings are applied on the front surface and anti-reflection coatings on the rear surface to prevent ghosting and to maximize transmission.\u003c\/p\u003e\u003cp\u003eHighly precise and accurate, the passbands of these filters remain spectrally stable and do not drift in response to extreme temperature fluctuations or changes in humidity. All filters may be used with apertures of f\/4 or smaller. They provide custom coating services for more demanding imaging applications requiring larger apertures such as f\/3 or f\/2. They also can provide larger sizes and unique passbands upon request.\u003c\/p\u003e","brand":"Chroma","offers":[{"title":"1.25\" Round Mounted","offer_id":44967245611293,"sku":"CT-27007-1.25M","price":644.0,"currency_code":"CAD","in_stock":true},{"title":"31mm Round Unmounted","offer_id":44967245644061,"sku":"CT-27007-31D","price":644.0,"currency_code":"CAD","in_stock":true},{"title":"36mm Round Unmounted","offer_id":44967245676829,"sku":"CT-27007-36D","price":868.0,"currency_code":"CAD","in_stock":true},{"title":"2\" Round Mounted","offer_id":44967245709597,"sku":"CT-27007-2M","price":1365.0,"currency_code":"CAD","in_stock":true},{"title":"50mm Round Unmounted","offer_id":44967245742365,"sku":"CT-27007-50D","price":1295.0,"currency_code":"CAD","in_stock":true},{"title":"50x50mm Square Unmounted","offer_id":44967245775133,"sku":"CT-27007-50X50","price":1932.0,"currency_code":"CAD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0753\/5280\/1565\/products\/Transmission-Curve-of-Chroma-OIII-5nm-Filter__52324.1596071514.1280.1280.jpg?v=1684339511"},{"product_id":"chroma-oiii-filter-8nm","title":"Chroma OIII Filter - 8nm","description":"\u003c!-- more --\u003e\u003cp\u003eChroma’s OIII filters isolate the 500.7nm primary emission line of doubly ionized oxygen. After H-alpha, this is the next most common emission when imaging nebulae\u003c\/p\u003e\u003cul\u003e\n\u003cli\u003eFilters designed for use with CCD and for f\/4.0 or slower\u003c\/li\u003e\n\u003cli\u003eNo reflections leading to image distortions or \"back reflections\"\u003c\/li\u003e\n\u003cli\u003eTransmitted wavefront better than 0.25 waves\/inch\u003c\/li\u003e\n\u003cli\u003eDurable sputter coatings\u003c\/li\u003e\n\u003cli\u003eParallelism: \u0026lt; 30 arcsec\u003c\/li\u003e\n\u003cli\u003eThickness: 3.0 +\/-0.05mm\u003c\/li\u003e\n\u003cli\u003eExtremely durable coatings withstand humidity changes and extreme temperature fluxes and remain spectrally accurate\u003c\/li\u003e\n\u003cli\u003ein CWL and band pass adherence\u003c\/li\u003e\n\u003cli\u003eCapable of manufacturing large filters for large detectors: 50mm x 50mm, 65mm up to 76.2mm and 101.6mm square\u003c\/li\u003e\n\u003cli\u003eAll filters manufactured in Vermont\u003c\/li\u003e\n\u003c\/ul\u003e\u003cp\u003eChroma manufactures the highest quality astronomy filters with durable, sputtered hard coatings using single substrates of the best glass, eliminating the need for laminations. All primary filter coatings are applied on the front surface and anti-reflection coatings on the rear surface to prevent ghosting and to maximize transmission.\u003c\/p\u003e\u003cp\u003eHighly precise and accurate, the passbands of these filters remain spectrally stable and do not drift in response to extreme temperature fluctuations or changes in humidity. All filters may be used with apertures of f\/4 or smaller. They provide custom coating services for more demanding imaging applications requiring larger apertures such as f\/3 or f\/2. They also can provide larger sizes and unique passbands upon request.\u003c\/p\u003e","brand":"Chroma","offers":[{"title":"1.25\" Round Mounted","offer_id":44967245807901,"sku":"CT-27008-1.25M","price":385.0,"currency_code":"CAD","in_stock":true},{"title":"31mm Round Unmounted","offer_id":44967245840669,"sku":"CT-27008-31D","price":385.0,"currency_code":"CAD","in_stock":true},{"title":"36mm Round Unmounted","offer_id":44967245873437,"sku":"CT-27008-36D","price":497.0,"currency_code":"CAD","in_stock":true},{"title":"2\" Round Mounted","offer_id":44967245906205,"sku":"CT-27008-2M","price":1162.0,"currency_code":"CAD","in_stock":true},{"title":"50mm Round Unmounted","offer_id":44967245938973,"sku":"CT-27008-50D","price":1092.0,"currency_code":"CAD","in_stock":true},{"title":"50x50mm Square Unmounted","offer_id":44967245971741,"sku":"CT-27008-50X50","price":1106.0,"currency_code":"CAD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0753\/5280\/1565\/products\/Transmission-Curve-of-Chroma-OIII-8nm-Filter__01564.1596071516.1280.1280.jpg?v=1684339515"},{"product_id":"chroma-luminance-filter","title":"Chroma Luminance Filter","description":"\u003c!-- more --\u003e\u003cp\u003eLuminance filter for enhancing color rendering with RGB set\u003c\/p\u003e\u003cul\u003e\n\u003cli\u003eFilters designed for use with CCD and for f\/4.0 or slower\u003c\/li\u003e\n\u003cli\u003eNo reflections leading to image distortions or \"back reflections\"\u003c\/li\u003e\n\u003cli\u003eTransmitted wavefront better than 0.25 waves\/inch\u003c\/li\u003e\n\u003cli\u003eDurable sputter coatings\u003c\/li\u003e\n\u003cli\u003eParallelism: \u0026lt; 30 arcsec\u003c\/li\u003e\n\u003cli\u003eThickness: 3.0 +\/-0.05mm\u003c\/li\u003e\n\u003cli\u003eExtremely durable coatings withstand humidity changes and extreme temperature fluxes and remain spectrally accurate\u003c\/li\u003e\n\u003cli\u003ein CWL and band pass adherence\u003c\/li\u003e\n\u003cli\u003eCapable of manufacturing large filters for large detectors: 50mm x 50mm, 65mm up to 76.2mm and 101.6mm square\u003c\/li\u003e\n\u003cli\u003eAll filters manufactured in Vermont\u003c\/li\u003e\n\u003c\/ul\u003e\u003cp\u003eChroma manufactures the highest quality astronomy filters with durable, sputtered hard coatings using single substrates of the best glass, eliminating the need for laminations. All primary filter coatings are applied on the front surface and anti-reflection coatings on the rear surface to prevent ghosting and to maximize transmission.\u003c\/p\u003e\u003cp\u003eHighly precise and accurate, the passbands of these filters remain spectrally stable and do not drift in response to extreme temperature fluctuations or changes in humidity. All filters may be used with apertures of f\/4 or smaller. They provide custom coating services for more demanding imaging applications requiring larger apertures such as f\/3 or f\/2. They also can provide larger sizes and unique passbands upon request.\u003c\/p\u003e","brand":"Chroma","offers":[{"title":"1.25\" Round Mounted","offer_id":44967246070045,"sku":"CT-27040-1.25M","price":210.0,"currency_code":"CAD","in_stock":true},{"title":"31mm Round Unmounted","offer_id":44967246102813,"sku":"CT-27040-31D","price":210.0,"currency_code":"CAD","in_stock":true},{"title":"36mm Round Unmounted","offer_id":44967246135581,"sku":"CT-27040-36D","price":315.0,"currency_code":"CAD","in_stock":true},{"title":"2\" Round Mounted","offer_id":44967246168349,"sku":"CT-27040-2M","price":700.0,"currency_code":"CAD","in_stock":true},{"title":"50mm Round Unmounted","offer_id":44967246201117,"sku":"CT-27040-50D","price":630.0,"currency_code":"CAD","in_stock":true},{"title":"50x50mm Square Unmounted","offer_id":44967246233885,"sku":"CT-27040-50X50","price":665.0,"currency_code":"CAD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0753\/5280\/1565\/products\/Transmission-Curve-of-Chroma-Luminance-Filter__08679.1596071517.1280.1280.jpg?v=1684339517"},{"product_id":"chroma-red-filter","title":"Chroma Red Filter","description":"\u003c!-- more --\u003e\u003cp\u003eRed filter for color rendering with RGB set\u003c\/p\u003e\u003cul\u003e\n\u003cli\u003eFilters designed for use with CCD and for f\/4.0 or slower\u003c\/li\u003e\n\u003cli\u003eNo reflections leading to image distortions or \"back reflections\"\u003c\/li\u003e\n\u003cli\u003eTransmitted wavefront better than 0.25 waves\/inch\u003c\/li\u003e\n\u003cli\u003eDurable sputter coatings\u003c\/li\u003e\n\u003cli\u003eParallelism: \u0026lt; 30 arcsec\u003c\/li\u003e\n\u003cli\u003eThickness: 3.0 +\/-0.05mm\u003c\/li\u003e\n\u003cli\u003eExtremely durable coatings withstand humidity changes and extreme temperature fluxes and remain spectrally accurate\u003c\/li\u003e\n\u003cli\u003ein CWL and band pass adherence\u003c\/li\u003e\n\u003cli\u003eCapable of manufacturing large filters for large detectors: 50mm x 50mm, 65mm up to 76.2mm and 101.6mm square\u003c\/li\u003e\n\u003cli\u003eAll filters manufactured in Vermont\u003c\/li\u003e\n\u003c\/ul\u003e\u003cp\u003eChroma manufactures the highest quality astronomy filters with durable, sputtered hard coatings using single substrates of the best glass, eliminating the need for laminations. All primary filter coatings are applied on the front surface and anti-reflection coatings on the rear surface to prevent ghosting and to maximize transmission.\u003c\/p\u003e\u003cp\u003eHighly precise and accurate, the passbands of these filters remain spectrally stable and do not drift in response to extreme temperature fluctuations or changes in humidity. All filters may be used with apertures of f\/4 or smaller. They provide custom coating services for more demanding imaging applications requiring larger apertures such as f\/3 or f\/2. They also can provide larger sizes and unique passbands upon request.\u003c\/p\u003e","brand":"Chroma","offers":[{"title":"1.25\" Round Mounted","offer_id":44967247708445,"sku":"CT-27041-1.25M","price":210.0,"currency_code":"CAD","in_stock":true},{"title":"31mm Round Unmounted","offer_id":44967247741213,"sku":"CT-27041-31D","price":210.0,"currency_code":"CAD","in_stock":true},{"title":"36mm Round Unmounted","offer_id":44967247773981,"sku":"CT-27041-36D","price":315.0,"currency_code":"CAD","in_stock":true},{"title":"2\" Round Mounted","offer_id":44967247806749,"sku":"CT-27041-2M","price":700.0,"currency_code":"CAD","in_stock":true},{"title":"50mm Round Unmounted","offer_id":44967247839517,"sku":"CT-27041-50D","price":630.0,"currency_code":"CAD","in_stock":true},{"title":"50x50mm Square Unmounted","offer_id":44967247872285,"sku":"CT-27041-50X50","price":665.0,"currency_code":"CAD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0753\/5280\/1565\/products\/Transmission-Curve-of-Chroma-Red-Filter__89625.1596071518.1280.1280.jpg?v=1684339717"},{"product_id":"chroma-green-filter","title":"Chroma Green Filter","description":"\u003c!-- more --\u003e\u003cp\u003eGreen filter for color rendering with RGB set\u003c\/p\u003e\u003cul\u003e\n\u003cli\u003eFilters designed for use with CCD and for f\/4.0 or slower\u003c\/li\u003e\n\u003cli\u003eNo reflections leading to image distortions or \"back reflections\"\u003c\/li\u003e\n\u003cli\u003eTransmitted wavefront better than 0.25 waves\/inch\u003c\/li\u003e\n\u003cli\u003eDurable sputter coatings\u003c\/li\u003e\n\u003cli\u003eParallelism: \u0026lt; 30 arcsec\u003c\/li\u003e\n\u003cli\u003eThickness: 3.0 +\/-0.05mm\u003c\/li\u003e\n\u003cli\u003eExtremely durable coatings withstand humidity changes and extreme temperature fluxes and remain spectrally accurate\u003c\/li\u003e\n\u003cli\u003ein CWL and band pass adherence\u003c\/li\u003e\n\u003cli\u003eCapable of manufacturing large filters for large detectors: 50mm x 50mm, 65mm up to 76.2mm and 101.6mm square\u003c\/li\u003e\n\u003cli\u003eAll filters manufactured in Vermont\u003c\/li\u003e\n\u003c\/ul\u003e\u003cp\u003eChroma manufactures the highest quality astronomy filters with durable, sputtered hard coatings using single substrates of the best glass, eliminating the need for laminations. All primary filter coatings are applied on the front surface and anti-reflection coatings on the rear surface to prevent ghosting and to maximize transmission.\u003c\/p\u003e\u003cp\u003eHighly precise and accurate, the passbands of these filters remain spectrally stable and do not drift in response to extreme temperature fluctuations or changes in humidity. All filters may be used with apertures of f\/4 or smaller. They provide custom coating services for more demanding imaging applications requiring larger apertures such as f\/3 or f\/2. They also can provide larger sizes and unique passbands upon request.\u003c\/p\u003e","brand":"Chroma","offers":[{"title":"1.25\" Round Mounted","offer_id":44967247905053,"sku":"CT-27042-1.25M","price":210.0,"currency_code":"CAD","in_stock":true},{"title":"31mm Round Unmounted","offer_id":44967247937821,"sku":"CT-27042-31D","price":210.0,"currency_code":"CAD","in_stock":true},{"title":"36mm Round Unmounted","offer_id":44967247970589,"sku":"CT-27042-36D","price":315.0,"currency_code":"CAD","in_stock":true},{"title":"2\" Round Mounted","offer_id":44967248003357,"sku":"CT-27042-2M","price":700.0,"currency_code":"CAD","in_stock":true},{"title":"50mm Round Unmounted","offer_id":44967248068893,"sku":"CT-27042-50D","price":630.0,"currency_code":"CAD","in_stock":true},{"title":"50x50mm Square Unmounted","offer_id":44967248101661,"sku":"CT-27042-50X50","price":665.0,"currency_code":"CAD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0753\/5280\/1565\/products\/Transmission-Curve-of-Chroma-Green-Filter__89486.1596071518.1280.1280.jpg?v=1684339719"},{"product_id":"chroma-blue-filter","title":"Chroma Blue Filter","description":"\u003c!-- more --\u003e\u003cp\u003eBlue filter for color rendering with RGB set\u003c\/p\u003e\u003cul\u003e\n\u003cli\u003eFilters designed for use with CCD and for f\/4.0 or slower\u003c\/li\u003e\n\u003cli\u003eNo reflections leading to image distortions or \"back reflections\"\u003c\/li\u003e\n\u003cli\u003eTransmitted wavefront better than 0.25 waves\/inch\u003c\/li\u003e\n\u003cli\u003eDurable sputter coatings\u003c\/li\u003e\n\u003cli\u003eParallelism: \u0026lt; 30 arcsec\u003c\/li\u003e\n\u003cli\u003eThickness: 3.0 +\/-0.05mm\u003c\/li\u003e\n\u003cli\u003eExtremely durable coatings withstand humidity changes and extreme temperature fluxes and remain spectrally accurate\u003c\/li\u003e\n\u003cli\u003ein CWL and band pass adherence\u003c\/li\u003e\n\u003cli\u003eCapable of manufacturing large filters for large detectors: 50mm x 50mm, 65mm up to 76.2mm and 101.6mm square\u003c\/li\u003e\n\u003cli\u003eAll filters manufactured in Vermont\u003c\/li\u003e\n\u003c\/ul\u003e\u003cp\u003eChroma manufactures the highest quality astronomy filters with durable, sputtered hard coatings using single substrates of the best glass, eliminating the need for laminations. All primary filter coatings are applied on the front surface and anti-reflection coatings on the rear surface to prevent ghosting and to maximize transmission.\u003c\/p\u003e\u003cp\u003eHighly precise and accurate, the passbands of these filters remain spectrally stable and do not drift in response to extreme temperature fluctuations or changes in humidity. All filters may be used with apertures of f\/4 or smaller. They provide custom coating services for more demanding imaging applications requiring larger apertures such as f\/3 or f\/2. They also can provide larger sizes and unique passbands upon request.\u003c\/p\u003e","brand":"Chroma","offers":[{"title":"1.25\" Round Mounted","offer_id":44967248134429,"sku":"CT-27043-1.25M","price":210.0,"currency_code":"CAD","in_stock":true},{"title":"31mm Round Unmounted","offer_id":44967248167197,"sku":"CT-27043-31D","price":210.0,"currency_code":"CAD","in_stock":true},{"title":"36mm Round Unmounted","offer_id":44967248199965,"sku":"CT-27043-36D","price":315.0,"currency_code":"CAD","in_stock":true},{"title":"2\" Round Mounted","offer_id":44967248232733,"sku":"CT-27043-2M","price":700.0,"currency_code":"CAD","in_stock":true},{"title":"50mm Round Unmounted","offer_id":44967248265501,"sku":"CT-27043-50D","price":630.0,"currency_code":"CAD","in_stock":true},{"title":"50x50mm Square Unmounted","offer_id":44967248298269,"sku":"CT-27043-50X50","price":665.0,"currency_code":"CAD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0753\/5280\/1565\/products\/Transmission-Curve-of-Chroma-Blue-Filter__36624.1596071519.1280.1280.jpg?v=1684339721"},{"product_id":"chroma-jovian-methane-filter","title":"Chroma Jovian Methane Filter","description":"\u003c!-- more --\u003e\u003cp\u003eMethane absorption band filter. This filter enhances contrast when imaging objects containing significant levels of methane. Methane-rich components, such as in the atmosphere of the Jovian planets, will appear darker.\u003c\/p\u003e\u003cul\u003e\n\u003cli\u003eFilters designed for use with CCD and for f\/4.0 or slower\u003c\/li\u003e\n\u003cli\u003eNo reflections leading to image distortions or \"back reflections\"\u003c\/li\u003e\n\u003cli\u003eTransmitted wavefront better than 0.25 waves\/inch\u003c\/li\u003e\n\u003cli\u003eDurable sputter coatings\u003c\/li\u003e\n\u003cli\u003eParallelism: \u0026lt; 30 arcsec\u003c\/li\u003e\n\u003cli\u003eThickness: 3.0 +\/-0.05mm\u003c\/li\u003e\n\u003cli\u003eExtremely durable coatings withstand humidity changes and extreme temperature fluxes and remain spectrally accurate\u003c\/li\u003e\n\u003cli\u003ein CWL and band pass adherence\u003c\/li\u003e\n\u003cli\u003eCapable of manufacturing large filters for large detectors: 50mm x 50mm, 65mm up to 76.2mm and 101.6mm square\u003c\/li\u003e\n\u003cli\u003eAll filters manufactured in Vermont\u003c\/li\u003e\n\u003c\/ul\u003e\u003cp\u003eChroma manufactures the highest quality astronomy filters with durable, sputtered hard coatings using single substrates of the best glass, eliminating the need for laminations. All primary filter coatings are applied on the front surface and anti-reflection coatings on the rear surface to prevent ghosting and to maximize transmission.\u003c\/p\u003e\u003cp\u003eHighly precise and accurate, the passbands of these filters remain spectrally stable and do not drift in response to extreme temperature fluctuations or changes in humidity. All filters may be used with apertures of f\/4 or smaller. They provide custom coating services for more demanding imaging applications requiring larger apertures such as f\/3 or f\/2. They also can provide larger sizes and unique passbands upon request.\u003c\/p\u003e","brand":"Chroma","offers":[{"title":"1.25\" Round Mounted","offer_id":44967248363805,"sku":"CT-27012-1.25M","price":385.0,"currency_code":"CAD","in_stock":true},{"title":"31mm Round Unmounted","offer_id":44967248396573,"sku":"CT-27012-31D","price":385.0,"currency_code":"CAD","in_stock":true},{"title":"36mm Round Unmounted","offer_id":44967248429341,"sku":"CT-27012-36D","price":497.0,"currency_code":"CAD","in_stock":true},{"title":"2\" Round Mounted","offer_id":44967248462109,"sku":"CT-27012-2M","price":707.0,"currency_code":"CAD","in_stock":true},{"title":"50mm Round Unmounted","offer_id":44967248494877,"sku":"CT-27012-50D","price":1092.0,"currency_code":"CAD","in_stock":true},{"title":"50x50mm Square Unmounted","offer_id":44967248527645,"sku":"CT-27012-50X50","price":1106.0,"currency_code":"CAD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0753\/5280\/1565\/products\/Transmission-Curve-of-Chroma-Jovian-Methane-Filter__29695.1596071520.1280.1280.jpg?v=1684339724"},{"product_id":"chroma-loglow-filter","title":"Chroma LoGlow Filter","description":"\u003c!-- more --\u003e\u003cp\u003eBlocks common spectral lines from lighting sources. This filter provides balanced color for the visible spectrum while blocking most emission from metal-halide and vapor lamp sources which together contribute to sky glow.\u003c\/p\u003e\u003cul\u003e\n\u003cli\u003eFilters designed for use with CCD and for f\/4.0 or slower\u003c\/li\u003e\n\u003cli\u003eNo reflections leading to image distortions or \"back reflections\"\u003c\/li\u003e\n\u003cli\u003eTransmitted wavefront better than 0.25 waves\/inch\u003c\/li\u003e\n\u003cli\u003eDurable sputter coatings\u003c\/li\u003e\n\u003cli\u003eParallelism: \u0026lt; 30 arcsec\u003c\/li\u003e\n\u003cli\u003eExtremely durable coatings withstand humidity changes and extreme temperature fluxes and remain spectrally accurate\u003c\/li\u003e\n\u003cli\u003ein CWL and band pass adherence\u003c\/li\u003e\n\u003cli\u003eCapable of manufacturing large filters for large detectors: 50mm x 50mm, 65mm up to 76.2mm and 101.6mm square\u003c\/li\u003e\n\u003cli\u003eAll filters manufactured in Vermont\u003c\/li\u003e\n\u003c\/ul\u003e\u003cp\u003eChroma manufactures the highest quality astronomy filters with durable, sputtered hard coatings using single substrates of the best glass, eliminating the need for laminations. All primary filter coatings are applied on the front surface and anti-reflection coatings on the rear surface to prevent ghosting and to maximize transmission.\u003c\/p\u003e\u003cp\u003eHighly precise and accurate, the passbands of these filters remain spectrally stable and do not drift in response to extreme temperature fluctuations or changes in humidity. All filters may be used with apertures of f\/4 or smaller. They provide custom coating services for more demanding imaging applications requiring larger apertures such as f\/3 or f\/2. They also can provide larger sizes and unique passbands upon request.\u003c\/p\u003e","brand":"Chroma","offers":[{"title":"1.25\" Round Mounted","offer_id":44967248593181,"sku":"CT-27030-1.25M","price":385.0,"currency_code":"CAD","in_stock":true},{"title":"31mm Round Unmounted","offer_id":44967248625949,"sku":"CT-27030-31D","price":385.0,"currency_code":"CAD","in_stock":true},{"title":"36mm Round Unmounted","offer_id":44967248658717,"sku":"CT-27030-36D","price":497.0,"currency_code":"CAD","in_stock":true},{"title":"2\" Round Mounted","offer_id":44967248691485,"sku":"CT-27030-2M","price":707.0,"currency_code":"CAD","in_stock":true},{"title":"50mm Round Unmounted","offer_id":44967248724253,"sku":"CT-27030-50D","price":637.0,"currency_code":"CAD","in_stock":true},{"title":"50x50mm Square Unmounted","offer_id":44967248757021,"sku":"CT-27030-50X50","price":770.0,"currency_code":"CAD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0753\/5280\/1565\/products\/Transmission-Curve-of-Chroma-LoGlow-Filter__74050.1596071521.1280.1280.jpg?v=1684339519"},{"product_id":"chroma-clear-filter","title":"Chroma Clear Filter","description":"\u003c!-- more --\u003e\u003cul\u003e\n\u003cli\u003eFilters designed for use with CCD and for f\/4.0 or slower\u003c\/li\u003e\n\u003cli\u003eNo reflections leading to image distortions or \"back reflections\"\u003c\/li\u003e\n\u003cli\u003eTransmitted wavefront better than 0.25 waves\/inch\u003c\/li\u003e\n\u003cli\u003eDurable sputter coatings\u003c\/li\u003e\n\u003cli\u003eParallelism: \u0026lt; 30 arcsec\u003c\/li\u003e\n\u003cli\u003eThickness: 3.0 +\/-0.05mm\u003c\/li\u003e\n\u003cli\u003eExtremely durable coatings withstand humidity changes and extreme temperature fluxes and remain spectrally accurate\u003c\/li\u003e\n\u003cli\u003ein CWL and band pass adherence\u003c\/li\u003e\n\u003cli\u003eCapable of manufacturing large filters for large detectors: 50mm x 50mm, 65mm up to 76.2mm and 101.6mm square\u003c\/li\u003e\n\u003cli\u003eAll filters manufactured in Vermont\u003c\/li\u003e\n\u003c\/ul\u003e\u003cp\u003eChroma manufactures the highest quality astronomy filters with durable, sputtered hard coatings using single substrates of the best glass, eliminating the need for laminations. All primary filter coatings are applied on the front surface and anti-reflection coatings on the rear surface to prevent ghosting and to maximize transmission.\u003c\/p\u003e\u003cp\u003eHighly precise and accurate, the passbands of these filters remain spectrally stable and do not drift in response to extreme temperature fluctuations or changes in humidity. All filters may be used with apertures of f\/4 or smaller. They provide custom coating services for more demanding imaging applications requiring larger apertures such as f\/3 or f\/2. They also can provide larger sizes and unique passbands upon request.\u003c\/p\u003e","brand":"Chroma","offers":[{"title":"1.25\" Round Mounted","offer_id":44967248822557,"sku":"CT-27044-1.25M","price":182.0,"currency_code":"CAD","in_stock":true},{"title":"31mm Round Unmounted","offer_id":44967248855325,"sku":"CT-27044-31D","price":182.0,"currency_code":"CAD","in_stock":true},{"title":"36mm Round Unmounted","offer_id":44967248888093,"sku":"CT-27044-36D","price":210.0,"currency_code":"CAD","in_stock":true},{"title":"2\" Round Mounted","offer_id":44967248920861,"sku":"CT-27044-2M","price":525.0,"currency_code":"CAD","in_stock":true},{"title":"50mm Round Unmounted","offer_id":44967248953629,"sku":"CT-27044-50D","price":455.0,"currency_code":"CAD","in_stock":true},{"title":"50x50mm Square Unmounted","offer_id":44967248986397,"sku":"CT-27044-50X50","price":490.0,"currency_code":"CAD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0753\/5280\/1565\/products\/Transmission-Curve-of-Chroma-Clear-Filter__90054.1596071523.1280.1280.jpg?v=1684339522"},{"product_id":"chroma-u-bessel-filter","title":"Chroma U-Bessel Filter","description":"\u003c!-- more --\u003e\u003cp\u003eUV photometric filter in UVBRI series\u003c\/p\u003e\u003cul\u003e\n\u003cli\u003eFilters designed for use with CCD and for f\/4.0 or slower\u003c\/li\u003e\n\u003cli\u003eNo reflections leading to image distortions or \"\"back reflections\"\"\u003c\/li\u003e\n\u003cli\u003eTransmitted wavefront better than 0.25 waves\/inch\u003c\/li\u003e\n\u003cli\u003eDurable sputter coatings\u003c\/li\u003e\n\u003cli\u003eParallelism: \u0026lt; 30 arcsec\u003c\/li\u003e\n\u003cli\u003eThickness: 3.0 +\/-0.05mm\u003c\/li\u003e\n\u003cli\u003eExtremely durable coatings withstand humidity changes and extreme temperature fluxes and remain spectrally accurate\u003c\/li\u003e\n\u003cli\u003ein CWL and band pass adherence\u003c\/li\u003e\n\u003cli\u003eCapable of manufacturing large filters for large detectors: 50mm x 50mm, 65mm up to 76.2mm and 101.6mm square\u003c\/li\u003e\n\u003cli\u003eAll filters manufactured in Vermont\u003c\/li\u003e\n\u003c\/ul\u003e\u003cp\u003eChroma manufactures the highest quality astronomy filters with durable, sputtered hard coatings using single substrates of the best glass, eliminating the need for laminations. All primary filter coatings are applied on the front surface and anti-reflection coatings on the rear surface to prevent ghosting and to maximize transmission.\u003c\/p\u003e\u003cp\u003eHighly precise and accurate, the passbands of these filters remain spectrally stable and do not drift in response to extreme temperature fluctuations or changes in humidity. All filters may be used with apertures of f\/4 or smaller. They provide custom coating services for more demanding imaging applications requiring larger apertures such as f\/3 or f\/2. They also can provide larger sizes and unique passbands upon request.\u003c\/p\u003e","brand":"Chroma","offers":[{"title":"1.25\" Round Mounted","offer_id":44967249051933,"sku":"CT-27050-1.25M","price":385.0,"currency_code":"CAD","in_stock":true},{"title":"31mm Round Unmounted","offer_id":44967249084701,"sku":"CT-27050-31D","price":385.0,"currency_code":"CAD","in_stock":true},{"title":"36mm Round Unmounted","offer_id":44967249117469,"sku":"CT-27050-36D","price":483.0,"currency_code":"CAD","in_stock":true},{"title":"2\" Round Mounted","offer_id":44967249150237,"sku":"CT-27050-2M","price":980.0,"currency_code":"CAD","in_stock":true},{"title":"50mm Round Unmounted","offer_id":44967249183005,"sku":"CT-27050-50D","price":910.0,"currency_code":"CAD","in_stock":true},{"title":"50x50mm Square Unmounted","offer_id":44967249215773,"sku":"CT-27050-50X50","price":1015.0,"currency_code":"CAD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0753\/5280\/1565\/products\/Transmission-Curve-of-Chroma-U-Bessel-Filter__84625.1596071523.1280.1280.jpg?v=1684339524"},{"product_id":"chroma-v-bessel-filter","title":"Chroma V-Bessel Filter","description":"\u003c!-- more --\u003e\u003cp\u003eGreen (Visible) photometric filter in UVBRI series\u003c\/p\u003e\u003cul\u003e\n\u003cli\u003eFilters designed for use with CCD and for f\/4.0 or slower\u003c\/li\u003e\n\u003cli\u003eNo reflections leading to image distortions or \"\"back reflections\"\"\u003c\/li\u003e\n\u003cli\u003eTransmitted wavefront better than 0.25 waves\/inch\u003c\/li\u003e\n\u003cli\u003eDurable sputter coatings\u003c\/li\u003e\n\u003cli\u003eParallelism: \u0026lt; 30 arcsec\u003c\/li\u003e\n\u003cli\u003eThickness: 3.0 +\/-0.05mm\u003c\/li\u003e\n\u003cli\u003eExtremely durable coatings withstand humidity changes and extreme temperature fluxes and remain spectrally accurate\u003c\/li\u003e\n\u003cli\u003ein CWL and band pass adherence\u003c\/li\u003e\n\u003cli\u003eCapable of manufacturing large filters for large detectors: 50mm x 50mm, 65mm up to 76.2mm and 101.6mm square\u003c\/li\u003e\n\u003cli\u003eAll filters manufactured in Vermont\u003c\/li\u003e\n\u003c\/ul\u003e\u003cp\u003eChroma manufactures the highest quality astronomy filters with durable, sputtered hard coatings using single substrates of the best glass, eliminating the need for laminations. All primary filter coatings are applied on the front surface and anti-reflection coatings on the rear surface to prevent ghosting and to maximize transmission.\u003c\/p\u003e\u003cp\u003eHighly precise and accurate, the passbands of these filters remain spectrally stable and do not drift in response to extreme temperature fluctuations or changes in humidity. All filters may be used with apertures of f\/4 or smaller. They provide custom coating services for more demanding imaging applications requiring larger apertures such as f\/3 or f\/2. They also can provide larger sizes and unique passbands upon request.\u003c\/p\u003e","brand":"Chroma","offers":[{"title":"1.25\" Round Mounted","offer_id":44967249281309,"sku":"CT-27051-1.25M","price":385.0,"currency_code":"CAD","in_stock":true},{"title":"31mm Round Unmounted","offer_id":44967249314077,"sku":"CT-27051-31D","price":385.0,"currency_code":"CAD","in_stock":true},{"title":"36mm Round Unmounted","offer_id":44967249346845,"sku":"CT-27051-36D","price":483.0,"currency_code":"CAD","in_stock":true},{"title":"2\" Round Mounted","offer_id":44967249379613,"sku":"CT-27051-2M","price":980.0,"currency_code":"CAD","in_stock":true},{"title":"50mm Round Unmounted","offer_id":44967249412381,"sku":"CT-27051-50D","price":910.0,"currency_code":"CAD","in_stock":true},{"title":"50x50mm Square Unmounted","offer_id":44967249445149,"sku":"CT-27051-50X50","price":1015.0,"currency_code":"CAD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0753\/5280\/1565\/products\/Transmission-Curve-of-Chroma-V-Bessel-Filter__56381.1596071524.1280.1280.jpg?v=1684339526"},{"product_id":"chroma-b-bessel-filter","title":"Chroma B-Bessel Filter","description":"\u003c!-- more --\u003e\u003cp\u003eBlue photometric filter in UVBRI series\u003c\/p\u003e\u003cul\u003e\n\u003cli\u003eFilters designed for use with CCD and for f\/4.0 or slower\u003c\/li\u003e\n\u003cli\u003eNo reflections leading to image distortions or \"\"back reflections\"\"\u003c\/li\u003e\n\u003cli\u003eTransmitted wavefront better than 0.25 waves\/inch\u003c\/li\u003e\n\u003cli\u003eDurable sputter coatings\u003c\/li\u003e\n\u003cli\u003eParallelism: \u0026lt; 30 arcsec\u003c\/li\u003e\n\u003cli\u003eThickness: 3.0 +\/-0.05mm\u003c\/li\u003e\n\u003cli\u003eExtremely durable coatings withstand humidity changes and extreme temperature fluxes and remain spectrally accurate\u003c\/li\u003e\n\u003cli\u003ein CWL and band pass adherence\u003c\/li\u003e\n\u003cli\u003eCapable of manufacturing large filters for large detectors: 50mm x 50mm, 65mm up to 76.2mm and 101.6mm square\u003c\/li\u003e\n\u003cli\u003eAll filters manufactured in Vermont\u003c\/li\u003e\n\u003c\/ul\u003e\u003cp\u003eChroma manufactures the highest quality astronomy filters with durable, sputtered hard coatings using single substrates of the best glass, eliminating the need for laminations. All primary filter coatings are applied on the front surface and anti-reflection coatings on the rear surface to prevent ghosting and to maximize transmission.\u003c\/p\u003e\u003cp\u003eHighly precise and accurate, the passbands of these filters remain spectrally stable and do not drift in response to extreme temperature fluctuations or changes in humidity. All filters may be used with apertures of f\/4 or smaller. They provide custom coating services for more demanding imaging applications requiring larger apertures such as f\/3 or f\/2. They also can provide larger sizes and unique passbands upon request.\u003c\/p\u003e","brand":"Chroma","offers":[{"title":"1.25\" Round Mounted","offer_id":44967249510685,"sku":"CT-27052-1.25M","price":385.0,"currency_code":"CAD","in_stock":true},{"title":"31mm Round Unmounted","offer_id":44967249543453,"sku":"CT-27052-31D","price":385.0,"currency_code":"CAD","in_stock":true},{"title":"36mm Round Unmounted","offer_id":44967249576221,"sku":"CT-27052-36D","price":483.0,"currency_code":"CAD","in_stock":true},{"title":"2\" Round Mounted","offer_id":44967249608989,"sku":"CT-27052-2M","price":980.0,"currency_code":"CAD","in_stock":true},{"title":"50mm Round Unmounted","offer_id":44967249641757,"sku":"CT-27052-50D","price":910.0,"currency_code":"CAD","in_stock":true},{"title":"50x50mm Square Unmounted","offer_id":44967249674525,"sku":"CT-27052-50X50","price":1015.0,"currency_code":"CAD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0753\/5280\/1565\/products\/Transmission-Curve-of-Chroma-B-Bessel-Filter__40887.1596071525.1280.1280.jpg?v=1684339528"},{"product_id":"chroma-r-bessel-filter","title":"Chroma R-Bessel Filter","description":"\u003c!-- more --\u003e\u003cp\u003eRed photometric filter in UVBRI series\u003c\/p\u003e\u003cul\u003e\n\u003cli\u003eFilters designed for use with CCD and for f\/4.0 or slower\u003c\/li\u003e\n\u003cli\u003eNo reflections leading to image distortions or \"\"back reflections\"\"\u003c\/li\u003e\n\u003cli\u003eTransmitted wavefront better than 0.25 waves\/inch\u003c\/li\u003e\n\u003cli\u003eDurable sputter coatings\u003c\/li\u003e\n\u003cli\u003eParallelism: \u0026lt; 30 arcsec\u003c\/li\u003e\n\u003cli\u003eThickness: 3.0 +\/-0.05mm\u003c\/li\u003e\n\u003cli\u003eExtremely durable coatings withstand humidity changes and extreme temperature fluxes and remain spectrally accurate\u003c\/li\u003e\n\u003cli\u003ein CWL and band pass adherence\u003c\/li\u003e\n\u003cli\u003eCapable of manufacturing large filters for large detectors: 50mm x 50mm, 65mm up to 76.2mm and 101.6mm square\u003c\/li\u003e\n\u003cli\u003eAll filters manufactured in Vermont\u003c\/li\u003e\n\u003c\/ul\u003e\u003cp\u003eChroma manufactures the highest quality astronomy filters with durable, sputtered hard coatings using single substrates of the best glass, eliminating the need for laminations. All primary filter coatings are applied on the front surface and anti-reflection coatings on the rear surface to prevent ghosting and to maximize transmission.\u003c\/p\u003e\u003cp\u003eHighly precise and accurate, the passbands of these filters remain spectrally stable and do not drift in response to extreme temperature fluctuations or changes in humidity. All filters may be used with apertures of f\/4 or smaller. They provide custom coating services for more demanding imaging applications requiring larger apertures such as f\/3 or f\/2. They also can provide larger sizes and unique passbands upon request.\u003c\/p\u003e","brand":"Chroma","offers":[{"title":"1.25\" Round Mounted","offer_id":44967249740061,"sku":"CT-27053-1.25M","price":385.0,"currency_code":"CAD","in_stock":true},{"title":"31mm Round Unmounted","offer_id":44967249772829,"sku":"CT-27053-31D","price":385.0,"currency_code":"CAD","in_stock":true},{"title":"36mm Round Unmounted","offer_id":44967249805597,"sku":"CT-27053-36D","price":483.0,"currency_code":"CAD","in_stock":true},{"title":"2\" Round Mounted","offer_id":44967249838365,"sku":"CT-27053-2M","price":980.0,"currency_code":"CAD","in_stock":true},{"title":"50mm Round Unmounted","offer_id":44967249871133,"sku":"CT-27053-50D","price":910.0,"currency_code":"CAD","in_stock":true},{"title":"50x50mm Square Unmounted","offer_id":44967249903901,"sku":"CT-27053-50X50","price":1015.0,"currency_code":"CAD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0753\/5280\/1565\/products\/Transmission-Curve-of-Chroma-R-Bessel-Filter__30129.1596071526.1280.1280.jpg?v=1684339726"},{"product_id":"chroma-i-bessel-filter","title":"Chroma I-Bessel Filter","description":"\u003c!-- more --\u003e\u003cp\u003eNIR photometric filter in UVBRI series\u003c\/p\u003e\u003cul\u003e\n\u003cli\u003eFilters designed for use with CCD and for f\/4.0 or slower\u003c\/li\u003e\n\u003cli\u003eNo reflections leading to image distortions or \"\"back reflections\"\"\u003c\/li\u003e\n\u003cli\u003eTransmitted wavefront better than 0.25 waves\/inch\u003c\/li\u003e\n\u003cli\u003eDurable sputter coatings\u003c\/li\u003e\n\u003cli\u003eParallelism: \u0026lt; 30 arcsec\u003c\/li\u003e\n\u003cli\u003eThickness: 3.0 +\/-0.05mm\u003c\/li\u003e\n\u003cli\u003eExtremely durable coatings withstand humidity changes and extreme temperature fluxes and remain spectrally accurate\u003c\/li\u003e\n\u003cli\u003ein CWL and band pass adherence\u003c\/li\u003e\n\u003cli\u003eCapable of manufacturing large filters for large detectors: 50mm x 50mm, 65mm up to 76.2mm and 101.6mm square\u003c\/li\u003e\n\u003cli\u003eAll filters manufactured in Vermont\u003c\/li\u003e\n\u003c\/ul\u003e\u003cp\u003eChroma manufactures the highest quality astronomy filters with durable, sputtered hard coatings using single substrates of the best glass, eliminating the need for laminations. All primary filter coatings are applied on the front surface and anti-reflection coatings on the rear surface to prevent ghosting and to maximize transmission.\u003c\/p\u003e\u003cp\u003eHighly precise and accurate, the passbands of these filters remain spectrally stable and do not drift in response to extreme temperature fluctuations or changes in humidity. All filters may be used with apertures of f\/4 or smaller. They provide custom coating services for more demanding imaging applications requiring larger apertures such as f\/3 or f\/2. They also can provide larger sizes and unique passbands upon request.\u003c\/p\u003e","brand":"Chroma","offers":[{"title":"1.25\" Round Mounted","offer_id":44967250034973,"sku":"CT-27054-1.25M","price":385.0,"currency_code":"CAD","in_stock":true},{"title":"31mm Round Unmounted","offer_id":44967250067741,"sku":"CT-27054-31D","price":385.0,"currency_code":"CAD","in_stock":true},{"title":"36mm Round Unmounted","offer_id":44967250100509,"sku":"CT-27054-36D","price":483.0,"currency_code":"CAD","in_stock":true},{"title":"2\" Round Mounted","offer_id":44967250133277,"sku":"CT-27054-2M","price":980.0,"currency_code":"CAD","in_stock":true},{"title":"50mm Round Unmounted","offer_id":44967250166045,"sku":"CT-27054-50D","price":910.0,"currency_code":"CAD","in_stock":true},{"title":"50x50mm Square Unmounted","offer_id":44967250198813,"sku":"CT-27054-50X50","price":1015.0,"currency_code":"CAD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0753\/5280\/1565\/products\/Transmission-Curve-of-Chroma-I-Bessel-Filter__54362.1596071527.1280.1280.jpg?v=1684339728"},{"product_id":"chroma-ubvri-filter-set","title":"Chroma UBVRI Filter Set","description":"\u003c!-- more --\u003e\u003cp\u003eUBVRI filter set for photometric imaging\u003c\/p\u003e\u003cul\u003e\n\u003cli\u003eFilters designed for use with CCD and for f\/4.0 or slower\u003c\/li\u003e\n\u003cli\u003eNo reflections leading to image distortions or \"\"back reflections\"\"\u003c\/li\u003e\n\u003cli\u003eTransmitted wavefront better than 0.25 waves\/inch\u003c\/li\u003e\n\u003cli\u003eDurable sputter coatings\u003c\/li\u003e\n\u003cli\u003eParallelism: \u0026lt; 30 arcsec\u003c\/li\u003e\n\u003cli\u003eThickness: 3.0 +\/-0.05mm\u003c\/li\u003e\n\u003cli\u003eExtremely durable coatings withstand humidity changes and extreme temperature fluxes and remain spectrally accurate\u003c\/li\u003e\n\u003cli\u003ein CWL and band pass adherence\u003c\/li\u003e\n\u003cli\u003eCapable of manufacturing large filters for large detectors: 50mm x 50mm, 65mm up to 76.2mm and 101.6mm square\u003c\/li\u003e\n\u003cli\u003eAll filters manufactured in Vermont\u003c\/li\u003e\n\u003c\/ul\u003e\u003cp\u003eChroma manufactures the highest quality astronomy filters with durable, sputtered hard coatings using single substrates of the best glass, eliminating the need for laminations. All primary filter coatings are applied on the front surface and anti-reflection coatings on the rear surface to prevent ghosting and to maximize transmission.\u003c\/p\u003e\u003cp\u003eHighly precise and accurate, the passbands of these filters remain spectrally stable and do not drift in response to extreme temperature fluctuations or changes in humidity. All filters may be used with apertures of f\/4 or smaller. They provide custom coating services for more demanding imaging applications requiring larger apertures such as f\/3 or f\/2. They also can provide larger sizes and unique passbands upon request.\u003c\/p\u003e","brand":"Chroma","offers":[{"title":"1.25\" Round Mounted","offer_id":44967250264349,"sku":"CT-27103-1.25M","price":1645.0,"currency_code":"CAD","in_stock":true},{"title":"31mm Round Unmounted","offer_id":44967250297117,"sku":"CT-27103-31D","price":2275.0,"currency_code":"CAD","in_stock":true},{"title":"36mm Round Unmounted","offer_id":44967250329885,"sku":"CT-27103-36D","price":2415.0,"currency_code":"CAD","in_stock":true},{"title":"2\" Round Mounted","offer_id":44967250362653,"sku":"CT-27103-2M","price":4620.0,"currency_code":"CAD","in_stock":true},{"title":"50mm Round Unmounted","offer_id":44967250395421,"sku":"CT-27103-50D","price":4270.0,"currency_code":"CAD","in_stock":true},{"title":"50x50mm Square Unmounted","offer_id":44967250428189,"sku":"CT-27103-50X50","price":4795.0,"currency_code":"CAD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0753\/5280\/1565\/products\/Transmission-Curve-of-Chroma-Bessel-UBVRI-Filters__13320.1596071528.1280.1280.jpg?v=1684339731"},{"product_id":"chroma-lrgb-filter-set","title":"Chroma LRGB Filter Set","description":"\u003c!-- more --\u003e\u003cp\u003eLuminance, Red, Green, and Blue astronomy filter set\u003c\/p\u003e\u003cul\u003e\n\u003cli\u003eFilters designed for use with CCD and for f\/4.0 or slower\u003c\/li\u003e\n\u003cli\u003eNo reflections leading to image distortions or \"\"back reflections\"\"\u003c\/li\u003e\n\u003cli\u003eTransmitted wavefront better than 0.25 waves\/inch\u003c\/li\u003e\n\u003cli\u003eDurable sputter coatings\u003c\/li\u003e\n\u003cli\u003eParallelism: \u0026lt; 30 arcsec\u003c\/li\u003e\n\u003cli\u003eThickness: 3.0 +\/-0.05mm\u003c\/li\u003e\n\u003cli\u003eExtremely durable coatings withstand humidity changes and extreme temperature fluxes and remain spectrally accurate\u003c\/li\u003e\n\u003cli\u003ein CWL and band pass adherence\u003c\/li\u003e\n\u003cli\u003eCapable of manufacturing large filters for large detectors: 50mm x 50mm, 65mm up to 76.2mm and 101.6mm square\u003c\/li\u003e\n\u003cli\u003eAll filters manufactured in Vermont\u003c\/li\u003e\n\u003c\/ul\u003e\u003cp\u003eChroma manufactures the highest quality astronomy filters with durable, sputtered hard coatings using single substrates of the best glass, eliminating the need for laminations. All primary filter coatings are applied on the front surface and anti-reflection coatings on the rear surface to prevent ghosting and to maximize transmission.\u003c\/p\u003e\u003cp\u003eHighly precise and accurate, the passbands of these filters remain spectrally stable and do not drift in response to extreme temperature fluctuations or changes in humidity. All filters may be used with apertures of f\/4 or smaller. They provide custom coating services for more demanding imaging applications requiring larger apertures such as f\/3 or f\/2. They also can provide larger sizes and unique passbands upon request.\u003c\/p\u003e","brand":"Chroma","offers":[{"title":"1.25\" Round Mounted","offer_id":44967250460957,"sku":"CT-27101-1.25M","price":735.0,"currency_code":"CAD","in_stock":true},{"title":"31mm Round Unmounted","offer_id":44967250493725,"sku":"CT-27101-31D","price":735.0,"currency_code":"CAD","in_stock":true},{"title":"36mm Round Unmounted","offer_id":44967250526493,"sku":"CT-27101-36D","price":1155.0,"currency_code":"CAD","in_stock":true},{"title":"2\" Round Mounted","offer_id":44967250559261,"sku":"CT-27101-2M","price":2695.0,"currency_code":"CAD","in_stock":true},{"title":"50mm Round Unmounted","offer_id":44967250592029,"sku":"CT-27101-50D","price":2415.0,"currency_code":"CAD","in_stock":true},{"title":"50x50mm Square Unmounted","offer_id":44967250624797,"sku":"CT-27101-50X50","price":2555.0,"currency_code":"CAD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0753\/5280\/1565\/products\/Transmission-Curve-of-Chroma-LRGB-Filters__96415.1596071530.1280.1280.jpg?v=1684339733"},{"product_id":"chroma-halrgb-filter-set","title":"Chroma HaLRGB Filter Set","description":"\u003c!-- more --\u003e\u003cp\u003e8nm H-alpha, Luminance, Red, Green, and Blue astronomy filter set\u003c\/p\u003e\u003cul\u003e\n\u003cli\u003eFilters designed for use with CCD and for f\/4.0 or slower\u003c\/li\u003e\n\u003cli\u003eNo reflections leading to image distortions or \"\"back reflections\"\"\u003c\/li\u003e\n\u003cli\u003eTransmitted wavefront better than 0.25 waves\/inch\u003c\/li\u003e\n\u003cli\u003eDurable sputter coatings\u003c\/li\u003e\n\u003cli\u003eParallelism: \u0026lt; 30 arcsec\u003c\/li\u003e\n\u003cli\u003eThickness: 3.0 +\/-0.05mm\u003c\/li\u003e\n\u003cli\u003eExtremely durable coatings withstand humidity changes and extreme temperature fluxes and remain spectrally accurate\u003c\/li\u003e\n\u003cli\u003ein CWL and band pass adherence\u003c\/li\u003e\n\u003cli\u003eCapable of manufacturing large filters for large detectors: 50mm x 50mm, 65mm up to 76.2mm and 101.6mm square\u003c\/li\u003e\n\u003cli\u003eAll filters manufactured in Vermont\u003c\/li\u003e\n\u003c\/ul\u003e\u003cp\u003eChroma manufactures the highest quality astronomy filters with durable, sputtered hard coatings using single substrates of the best glass, eliminating the need for laminations. All primary filter coatings are applied on the front surface and anti-reflection coatings on the rear surface to prevent ghosting and to maximize transmission.\u003c\/p\u003e\u003cp\u003eHighly precise and accurate, the passbands of these filters remain spectrally stable and do not drift in response to extreme temperature fluctuations or changes in humidity. All filters may be used with apertures of f\/4 or smaller. They provide custom coating services for more demanding imaging applications requiring larger apertures such as f\/3 or f\/2. They also can provide larger sizes and unique passbands upon request.\u003c\/p\u003e","brand":"Chroma","offers":[{"title":"1.25\" Round Mounted \/ 8nm","offer_id":44967250723101,"sku":"CT-27102-1.25M","price":1085.0,"currency_code":"CAD","in_stock":true},{"title":"1.25\" Round Mounted \/ 5nm","offer_id":44967250755869,"sku":"CT-HA5LRGB-1.25M","price":1344.0,"currency_code":"CAD","in_stock":true},{"title":"1.25\" Round Mounted \/ 3nm","offer_id":44967250788637,"sku":"CT-HA3LRGB-1.25M","price":1505.0,"currency_code":"CAD","in_stock":true},{"title":"31mm Round Unmounted \/ 8nm","offer_id":44967250821405,"sku":"CT-27102-31D","price":1085.0,"currency_code":"CAD","in_stock":true},{"title":"31mm Round Unmounted \/ 5nm","offer_id":44967250854173,"sku":"CT-HA5LRGB-31D","price":1344.0,"currency_code":"CAD","in_stock":true},{"title":"31mm Round Unmounted \/ 3nm","offer_id":44967250886941,"sku":"CT-HA3LRGB-31D","price":1505.0,"currency_code":"CAD","in_stock":true},{"title":"36mm Round Unmounted \/ 8nm","offer_id":44967250919709,"sku":"CT-27102-36D","price":1617.0,"currency_code":"CAD","in_stock":true},{"title":"36mm Round Unmounted \/ 5nm","offer_id":44967250952477,"sku":"CT-HA5LRGB-36D","price":1988.0,"currency_code":"CAD","in_stock":true},{"title":"36mm Round Unmounted \/ 3nm","offer_id":44967250985245,"sku":"CT-HA3LRGB-36D","price":2205.0,"currency_code":"CAD","in_stock":true},{"title":"2\" Round Mounted \/ 8nm","offer_id":44967251018013,"sku":"CT-27102-2M","price":3822.0,"currency_code":"CAD","in_stock":true},{"title":"2\" Round Mounted \/ 5nm","offer_id":44967251050781,"sku":"CT-HA5LRGB-2M","price":4025.0,"currency_code":"CAD","in_stock":true},{"title":"2\" Round Mounted \/ 3nm","offer_id":44967251083549,"sku":"CT-HA3LRGB-2M","price":4480.0,"currency_code":"CAD","in_stock":true},{"title":"50mm Round Unmounted \/ 8nm","offer_id":44967251116317,"sku":"CT-27102-50D","price":3472.0,"currency_code":"CAD","in_stock":true},{"title":"50mm Round Unmounted \/ 5nm","offer_id":44967251149085,"sku":"CT-HA5LRGB-50D","price":3675.0,"currency_code":"CAD","in_stock":true},{"title":"50mm Round Unmounted \/ 3nm","offer_id":44967251181853,"sku":"CT-HA3LRGB-50D","price":4130.0,"currency_code":"CAD","in_stock":true},{"title":"50x50mm Square Unmounted \/ 8nm","offer_id":44967251214621,"sku":"CT-27102-50X50","price":3626.0,"currency_code":"CAD","in_stock":true},{"title":"50x50mm Square Unmounted \/ 5nm","offer_id":44967251247389,"sku":"CT-HA5LRGB-50X50","price":4452.0,"currency_code":"CAD","in_stock":true},{"title":"50x50mm Square Unmounted \/ 3nm","offer_id":44967251280157,"sku":"CT-HA3LRGB-50X50","price":4690.0,"currency_code":"CAD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0753\/5280\/1565\/products\/Transmission-Curve-of-Chroma-HaLRGB-Filters__04231.1596071532.1280.1280.jpg?v=1684339530"},{"product_id":"chroma-h-alpha-filter-optimized-for-f-3-3nm","title":"Chroma H-alpha Filter Optimized for f\/3 - 3nm","description":"\u003c!-- more --\u003e\u003cp\u003eH-alpha filters are essential for imaging nebulae and other objects which are rich in ionized hydrogen. At 656.3nm, a narrow-band emission filter is required to separate H-alpha from the SII doublet (671.6nm and 673.1nm).\u003c\/p\u003e\u003cul\u003e\n\u003cli\u003eFilters designed for use with CCD and for f\/3.0 telescopes\u003c\/li\u003e\n\u003cli\u003eNo reflections leading to image distortions or \"back reflections\"\u003c\/li\u003e\n\u003cli\u003eTransmitted wavefront better than 0.25 waves\/inch\u003c\/li\u003e\n\u003cli\u003eDurable sputter coatings\u003c\/li\u003e\n\u003cli\u003eParallelism: \u0026lt; 30 arcsec\u003c\/li\u003e\n\u003cli\u003eThickness: 3.0 +\/-0.05mm\u003c\/li\u003e\n\u003cli\u003eExtremely durable coatings withstand humidity changes and extreme temperature fluxes and remain spectrally accurate\u003c\/li\u003e\n\u003cli\u003ein CWL and band pass adherence\u003c\/li\u003e\n\u003cli\u003eCapable of manufacturing large filters for large detectors: 50mm x 50mm, 65mm up to 76.2mm and 101.6mm square\u003c\/li\u003e\n\u003cli\u003eAll filters manufactured in Vermont\u003c\/li\u003e\n\u003c\/ul\u003e\u003cp\u003eChroma manufactures the highest quality astronomy filters with durable, sputtered hard coatings using single substrates of the best glass, eliminating the need for laminations. All primary filter coatings are applied on the front surface and anti-reflection coatings on the rear surface to prevent ghosting and to maximize transmission.\u003c\/p\u003e\u003cp\u003eHighly precise and accurate, the passbands of these filters remain spectrally stable and do not drift in response to extreme temperature fluctuations or changes in humidity. They also can provide larger sizes and unique passbands upon request.\u003c\/p\u003e","brand":"Chroma","offers":[{"title":"1.25\" Round Mounted","offer_id":44967251378461,"sku":"CT-27001F3-1.25M","price":805.0,"currency_code":"CAD","in_stock":true},{"title":"31mm Round Unmounted","offer_id":44967251411229,"sku":"CT-27001F3-31D","price":805.0,"currency_code":"CAD","in_stock":true},{"title":"36mm Round Unmounted","offer_id":44967251443997,"sku":"CT-27001F3-36D","price":1085.0,"currency_code":"CAD","in_stock":true},{"title":"2\" Round Mounted","offer_id":44967251476765,"sku":"CT-27001F3-2M","price":1820.0,"currency_code":"CAD","in_stock":true},{"title":"50mm Round Unmounted","offer_id":44967251509533,"sku":"CT-27001F3-50D","price":1750.0,"currency_code":"CAD","in_stock":true},{"title":"50x50mm Square Unmounted","offer_id":44967251542301,"sku":"CT-27001F3-50X50","price":2170.0,"currency_code":"CAD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0753\/5280\/1565\/products\/Transmission-Curve-of-Chroma-H-alpha-3nm-Filter__61895.1596071533.1280.1280.jpg?v=1684339534"},{"product_id":"chroma-sii-filter-optimized-for-f-3-3nm","title":"Chroma SII Filter Optimized for f\/3 - 3nm","description":"\u003c!-- more --\u003e\u003cp\u003eSII filters isolate the spectral emission of singly ionized sulfur atoms, also common in nebulae. Emission is at two lines occurring as a doublet, at 671.6 and 673.1 nm. This filter also separates sulfur emission from H-alpha emission (656.3nm).\u003c\/p\u003e\u003cul\u003e\n\u003cli\u003eFilters designed for use with CCD and for f\/3.0 telescopes\u003c\/li\u003e\n\u003cli\u003eNo reflections leading to image distortions or \"back reflections\"\u003c\/li\u003e\n\u003cli\u003eTransmitted wavefront better than 0.25 waves\/inch\u003c\/li\u003e\n\u003cli\u003eDurable sputter coatings\u003c\/li\u003e\n\u003cli\u003eParallelism: \u0026lt; 30 arcsec\u003c\/li\u003e\n\u003cli\u003eThickness: 3.0 +\/-0.05mm\u003c\/li\u003e\n\u003cli\u003eExtremely durable coatings withstand humidity changes and extreme temperature fluxes and remain spectrally accurate\u003c\/li\u003e\n\u003cli\u003ein CWL and band pass adherence\u003c\/li\u003e\n\u003cli\u003eCapable of manufacturing large filters for large detectors: 50mm x 50mm, 65mm up to 76.2mm and 101.6mm square\u003c\/li\u003e\n\u003cli\u003eAll filters manufactured in Vermont\u003c\/li\u003e\n\u003c\/ul\u003e\u003cp\u003eChroma manufactures the highest quality astronomy filters with durable, sputtered hard coatings using single substrates of the best glass, eliminating the need for laminations. All primary filter coatings are applied on the front surface and anti-reflection coatings on the rear surface to prevent ghosting and to maximize transmission.\u003c\/p\u003e\u003cp\u003eHighly precise and accurate, the passbands of these filters remain spectrally stable and do not drift in response to extreme temperature fluctuations or changes in humidity. They also can provide larger sizes and unique passbands upon request.\u003c\/p\u003e","brand":"Chroma","offers":[{"title":"1.25\" Round Mounted","offer_id":44967252099357,"sku":"CT-27009F3-1.25M","price":805.0,"currency_code":"CAD","in_stock":true},{"title":"31mm Round Unmounted","offer_id":44967252132125,"sku":"CT-27009F3-31D","price":805.0,"currency_code":"CAD","in_stock":true},{"title":"36mm Round Unmounted","offer_id":44967252164893,"sku":"CT-27009F3-36D","price":1085.0,"currency_code":"CAD","in_stock":true},{"title":"2\" Round Mounted","offer_id":44967252197661,"sku":"CT-27009F3-2M","price":1820.0,"currency_code":"CAD","in_stock":true},{"title":"50mm Round Unmounted","offer_id":44967252230429,"sku":"CT-27009F3-50D","price":1750.0,"currency_code":"CAD","in_stock":true},{"title":"50x50mm Square Unmounted","offer_id":44967252263197,"sku":"CT-27009F3-50X50","price":2170.0,"currency_code":"CAD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0753\/5280\/1565\/products\/Transmission-Curve-of-Chroma-SII-3nm-Filter__73590.1596071536.1280.1280.jpg?v=1684339736"},{"product_id":"chroma-oiii-filter-optimized-for-f-3-3nm","title":"Chroma OIII Filter Optimized for f\/3 - 3nm","description":"\u003c!-- more --\u003e\u003cp\u003eChroma’s OIII filters isolate the 500.7nm primary emission line of doubly ionized oxygen. After H-alpha, this is the next most common emission when imaging nebulae\u003c\/p\u003e\u003cul\u003e\n\u003cli\u003eFilters designed for use with CCD and for f\/3.0 telescopes\u003c\/li\u003e\n\u003cli\u003eNo reflections leading to image distortions or \"back reflections\"\u003c\/li\u003e\n\u003cli\u003eTransmitted wavefront better than 0.25 waves\/inch\u003c\/li\u003e\n\u003cli\u003eDurable sputter coatings\u003c\/li\u003e\n\u003cli\u003eParallelism: \u0026lt; 30 arcsec\u003c\/li\u003e\n\u003cli\u003eThickness: 3.0 +\/-0.05mm\u003c\/li\u003e\n\u003cli\u003eExtremely durable coatings withstand humidity changes and extreme temperature fluxes and remain spectrally accurate\u003c\/li\u003e\n\u003cli\u003ein CWL and band pass adherence\u003c\/li\u003e\n\u003cli\u003eCapable of manufacturing large filters for large detectors: 50mm x 50mm, 65mm up to 76.2mm and 101.6mm square\u003c\/li\u003e\n\u003cli\u003eAll filters manufactured in Vermont\u003c\/li\u003e\n\u003c\/ul\u003e\u003cp\u003eChroma manufactures the highest quality astronomy filters with durable, sputtered hard coatings using single substrates of the best glass, eliminating the need for laminations. All primary filter coatings are applied on the front surface and anti-reflection coatings on the rear surface to prevent ghosting and to maximize transmission.\u003c\/p\u003e\u003cp\u003eHighly precise and accurate, the passbands of these filters remain spectrally stable and do not drift in response to extreme temperature fluctuations or changes in humidity. They also can provide larger sizes and unique passbands upon request.\u003c\/p\u003e","brand":"Chroma","offers":[{"title":"1.25\" Round Mounted","offer_id":44967252754717,"sku":"CT-27006F3-1.25M","price":805.0,"currency_code":"CAD","in_stock":true},{"title":"31mm Round Unmounted","offer_id":44967252820253,"sku":"CT-27006F3-31D","price":805.0,"currency_code":"CAD","in_stock":true},{"title":"36mm Round Unmounted","offer_id":44967252853021,"sku":"CT-27006F3-36D","price":1085.0,"currency_code":"CAD","in_stock":true},{"title":"2\" Round Mounted","offer_id":44967252885789,"sku":"CT-27006F3-2M","price":1820.0,"currency_code":"CAD","in_stock":true},{"title":"50mm Round Unmounted","offer_id":44967252918557,"sku":"CT-27006F3-50D","price":1750.0,"currency_code":"CAD","in_stock":true},{"title":"50x50mm Square Unmounted","offer_id":44967252951325,"sku":"CT-27006F3-50X50","price":2170.0,"currency_code":"CAD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0753\/5280\/1565\/products\/Transmission-Curve-of-Chroma-OIII-3nm-Filter__18267.1596071539.1280.1280.jpg?v=1684339747"},{"product_id":"baader-acf-dslr-astro-conversion-filter-for-canon-eos-300","title":"Baader ACF DSLR Astro Conversion Filter - for Canon EOS 300","description":"\u003cul class=\"DAV-feature-list\"\u003e\n\u003cli\u003eDesigned for Canon EOS 300 DSLR Astro-Conversion\u003c\/li\u003e\n\u003cli\u003eDramatically Improved Spectral Transmission for Astrophotography\u003c\/li\u003e\n\u003cli\u003eUnlocks Critical Hydrogen-Alpha (Hα) Wavelengths\u003c\/li\u003e\n\u003cli\u003ePlane-Optically Polished for Maximum Image Fidelity\u003c\/li\u003e\n\u003cli\u003eReplaces the Camera's Stock Internal Filter\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 ACF DSLR Astro Conversion Filter - for Canon EOS 300\u003c\/h2\u003e\n      \u003cp\u003eThe Baader ACF 1 Astro Conversion Filter is engineered specifically for the Canon EOS 300, replacing the stock internal filter to dramatically improve spectral transmission for astrophotography. This plane-optically polished filter is the key to unlocking the deep-red hydrogen-alpha wavelengths essential for capturing the true structure and extent of emission nebulae.\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\u003eUnlocking H-alpha: The Purpose of the Baader ACF Filter\u003c\/h3\u003e\n      \u003cp\u003eA standard DSLR camera's internal filter is designed to block infrared light and a significant portion of the deep-red spectrum to produce pleasing daytime images. This same filter, however, aggressively cuts off the 656nm Hydrogen-alpha line, which is the dominant wavelength emitted by the vast majority of nebulae. The Baader ACF filter corrects this by replacing the stock filter with one that has an \"astro-tuned\" transmission curve, allowing this vital wavelength to reach your camera's sensor.\u003c\/p\u003e\n      \u003cp\u003eWith this filter installed, your Canon EOS 300 can capture the faint, glowing hydrogen gas in objects like the North American Nebula (NGC 7000) or the Rosette Nebula (NGC 2244), revealing details and structures that are simply invisible to an unmodified camera.\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\u003ePlane Optical Polishing: Maintaining Image Sharpness\u003c\/h3\u003e\n      \u003cp\u003eInserting any filter into an optical path risks degrading the image, but the Baader ACF filter is manufactured to prevent this. It is plane-optically polished to a high standard, ensuring it does not introduce astigmatism, blur, or other aberrations into your images. This preserves the sharpness and resolution delivered by your telescope or camera lens.\u003c\/p\u003e\n      \u003cp\u003eThis level of optical quality means your stars remain tight, round points from edge to edge. The filter's only job is to alter the spectral transmission, not the geometric accuracy of the light cone, ensuring your final images are as sharp as your optics can deliver.\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\u003eStock vs. Astro-Modified: What the ACF Filter Changes for Your Canon EOS 300\u003c\/h3\u003e\n      \u003cp\u003eModifying your Canon EOS 300 with the Baader ACF filter fundamentally changes its behavior, turning it into a specialized instrument for astronomy. A stock camera will produce weak, muted reds when aimed at emission nebulae, often requiring extreme processing to show even a hint of structure. After modification, the H-alpha signal is dramatically stronger, making nebulae stand out with far less exposure time and noise.\u003c\/p\u003e\n      \u003cp\u003eThe primary trade-off is in daytime photography. The increased red sensitivity will shift the camera's color balance, requiring a custom white balance profile to produce natural-looking terrestrial images. For many, this modification dedicates the camera body to astrophotography, where its newfound sensitivity can be fully exploited.\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\"\u003eWhat is the main benefit of installing the Baader ACF Filter in my Canon EOS 300?\u003c\/h3\u003e\n  \u003c\/div\u003e\n  \u003cdiv class=\"DAV-accordion-A\"\u003e\n    \u003cp\u003eThe primary benefit is a massive increase in sensitivity to the \u003cstrong\u003eHydrogen-alpha (Hα) wavelength\u003c\/strong\u003e at 656nm. This allows your Canon EOS 300 to capture the faint, red light from emission nebulae, which is almost completely blocked by the camera's original factory filter.\u003c\/p\u003e\n  \u003c\/div\u003e\n  \u003cdiv class=\"DAV-accordion\"\u003e\n    \u003ch3 class=\"DAV-accordion-Q\"\u003eHow will the Baader ACF Filter change my images of the Orion Nebula (M42) with my Canon EOS 300?\u003c\/h3\u003e\n  \u003c\/div\u003e\n  \u003cdiv class=\"DAV-accordion-A\"\u003e\n    \u003cp\u003eWith an unmodified Canon EOS 300, the extensive outer loops of hydrogen gas in the Orion Nebula (M42) will appear faint and lack detail. After installing the Baader ACF filter, these structures will be significantly brighter and more defined in your exposures, revealing the full extent of the nebula with much greater contrast and color depth.\u003c\/p\u003e\n  \u003c\/div\u003e\n  \u003cdiv class=\"DAV-accordion\"\u003e\n    \u003ch3 class=\"DAV-accordion-Q\"\u003eCan I still use my Canon EOS 300 for normal daytime photography after installing the Baader ACF filter?\u003c\/h3\u003e\n  \u003c\/div\u003e\n  \u003cdiv class=\"DAV-accordion-A\"\u003e\n    \u003cp\u003eYes, but with a critical adjustment. The increased red sensitivity will give daytime images a strong red cast. To correct this, you must create a \u003cstrong\u003ecustom white balance\u003c\/strong\u003e profile using a grey card. While usable, many astrophotographers choose to dedicate the modified camera body to astronomical use.\u003c\/p\u003e\n  \u003c\/div\u003e\n  \u003cdiv class=\"DAV-accordion\"\u003e\n    \u003ch3 class=\"DAV-accordion-Q\"\u003eWhy is \"plane optical polishing\" important for the Baader ACF conversion filter?\u003c\/h3\u003e\n  \u003c\/div\u003e\n  \u003cdiv class=\"DAV-accordion-A\"\u003e\n    \u003cp\u003ePlane optical polishing ensures the filter is perfectly flat and free of optical defects. This is crucial because a low-quality filter can distort the light path, leading to \u003cstrong\u003eblurred stars and loss of detail\u003c\/strong\u003e. Baader's polishing maintains the high-resolution performance of your telescope and lenses.\u003c\/p\u003e\n  \u003c\/div\u003e\n  \u003cdiv class=\"DAV-accordion\"\u003e\n    \u003ch3 class=\"DAV-accordion-Q\"\u003eI use my Canon EOS 300 with an 80mm refractor. Will the Baader ACF filter introduce any optical problems?\u003c\/h3\u003e\n  \u003c\/div\u003e\n  \u003cdiv class=\"DAV-accordion-A\"\u003e\n    \u003cp\u003eNo. Because the Baader ACF filter is plane-optically polished, it will not introduce any new aberrations like astigmatism or coma. It is designed to be optically transparent in terms of image geometry, so the sharp, high-contrast views from your 80mm refractor will be preserved.\u003c\/p\u003e\n  \u003c\/div\u003e\n  \u003cdiv class=\"DAV-accordion\"\u003e\n    \u003ch3 class=\"DAV-accordion-Q\"\u003eIs installing the Baader ACF filter a simple process?\u003c\/h3\u003e\n  \u003c\/div\u003e\n  \u003cdiv class=\"DAV-accordion-A\"\u003e\n    \u003cp\u003eInstalling a DSLR conversion filter is a delicate and complex procedure that involves disassembling the camera body in a dust-free environment. It carries a risk of damaging the sensor or camera electronics. We strongly recommend having the \u003cstrong\u003einstallation performed by an experienced professional\u003c\/strong\u003e.\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\u003eFilter size\u003c\/td\u003e\n\u003ctd\u003eother\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eFilter shape\u003c\/td\u003e\n\u003ctd\u003erectangular\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eSingle or Set?\u003c\/td\u003e\n\u003ctd\u003eSingle Filter\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eFilter mounted\u003c\/td\u003e\n\u003ctd\u003eUnmounted\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eFilter Usage\u003c\/td\u003e\n\u003ctd\u003eColor Correction, H-alpha, IR-Cut, UV-Cut\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eTransmission Range\u003c\/td\u003e\n\u003ctd\u003e400 – 700 nm\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eAR-Coating\u003c\/td\u003e\n\u003ctd\u003edielectrically coated, planeoptically polished\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    \n  \u003c\/ul\u003e\n\u003c\/li\u003e\n\n\u003cli\u003e\n\u003cul class=\"DAV-grid\"\u003e\n\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":44967355842845,"sku":"BAA-2459211","price":124.0,"currency_code":"CAD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0753\/5280\/1565\/products\/Baader-ACF-DSLR-Astro-Conversion-Filter-for-Canon-EOS-300-1__99449.1597110898.1280.1280.jpg?v=1684340980"},{"product_id":"baader-acf-dslr-astro-conversion-filter-for-canon-eos-350d-10d-20d-30d","title":"Baader ACF DSLR Astro Conversion Filter - for Canon EOS 350D\/10D\/20D\/30D","description":"\u003cul class=\"DAV-feature-list\"\u003e\n\u003cli\u003eDesigned for Canon EOS 350D, 10D, 20D, and 30D DSLRs\u003c\/li\u003e\n\u003cli\u003eImproves Spectral Transmission for Astrophotography\u003c\/li\u003e\n\u003cli\u003eUnlocks Sensitivity to Hydrogen-Alpha (Hα) Nebulae\u003c\/li\u003e\n\u003cli\u003ePlane-Optically Polished to Maintain Image Sharpness\u003c\/li\u003e\n\u003cli\u003eReplaces the Camera's Stock Internal Low-Pass Filter\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 ACF DSLR Astro Conversion Filter - for Canon EOS 350D\/10D\/20D\/30D\u003c\/h2\u003e\n\u003cp\u003eThe Baader ACF DSLR Astro Conversion Filter is a direct replacement for the stock low-pass filter in Canon EOS 350D, 10D, 20D, and 30D cameras. This plane-optically polished filter unlocks your DSLR's true deep-sky potential by providing improved spectral transmission, especially in the critical Hydrogen-alpha wavelength, turning a standard camera into a dedicated astronomical imaging tool.\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\u003eUnlocking H-Alpha for Deep-Sky Astrophotography\u003c\/h3\u003e\n\u003cp\u003eStandard DSLR cameras include an internal filter that aggressively blocks infrared light to ensure correct color balance for daytime photography. A side effect is that this filter also cuts off the vital 656nm Hydrogen-alpha line, the wavelength in which most emission nebulae shine brightest. The Baader ACF filter is engineered to replace the stock filter, providing a spectral window that allows this deep red light to reach your camera's sensor.\u003c\/p\u003e\n\u003cp\u003eBy installing this filter, you convert your camera into a powerful instrument for capturing faint, red nebulosity. Objects like the North American Nebula (NGC 7000) and the Rosette Nebula (NGC 2237), which are nearly invisible to an unmodified camera, will register with rich detail and contrast, revealing the vast hydrogen clouds that populate our galaxy.\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\u003ePlane-Polished Glass for Maintained Sharpness\u003c\/h3\u003e\n\u003cp\u003ePlacing any new optical element in a camera's light path carries the risk of degrading image resolution if not manufactured to high standards. Baader addresses this by ensuring the ACF filter is plane-optically polished. This process results in surfaces that are exceptionally flat and parallel, preventing any distortion of the focal plane.\u003c\/p\u003e\n\u003cp\u003eThis attention to optical quality means your stars remain pinpoint and fine details are preserved across the entire frame. The filter's purpose is to improve spectral response without compromising the sharpness your telescope and camera sensor are capable of delivering, ensuring your final images are both sensitive and sharp.\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 purpose of the Baader ACF Astro Conversion Filter for my Canon 20D?\u003c\/h3\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion-A\"\u003e\n\u003cp\u003eThis filter replaces your Canon 20D's original internal filter, which blocks most of the red light from deep-sky nebulae. The Baader ACF filter allows this critical \u003cstrong\u003eHydrogen-alpha light\u003c\/strong\u003e to pass through, dramatically increasing your camera's sensitivity for astrophotography of emission nebulae.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion\"\u003e\n\u003ch3 class=\"DAV-accordion-Q\"\u003eWill installing the Baader ACF filter change how my Canon 350D works for daytime photography?\u003c\/h3\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion-A\"\u003e\n\u003cp\u003eYes. After this modification, your camera's color balance will be strongly shifted toward red. While it's possible to correct this with a \u003cstrong\u003ecustom white balance\u003c\/strong\u003e, the camera is best considered a dedicated astronomy tool post-conversion. Autofocus with standard camera lenses may also be affected.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion\"\u003e\n\u003ch3 class=\"DAV-accordion-Q\"\u003eWhy is this Baader filter better than just removing the stock filter from my Canon 10D?\u003c\/h3\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion-A\"\u003e\n\u003cp\u003eSimply removing the stock filter alters the camera's required back focus distance, making it impossible to reach infinity focus with many lenses and telescopes. The Baader ACF filter is a \u003cstrong\u003eplane-parallel replacement\u003c\/strong\u003e that maintains the correct optical path length, ensuring sharp focus while also protecting the exposed CMOS sensor from dust.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion\"\u003e\n\u003ch3 class=\"DAV-accordion-Q\"\u003eWhat objects will I image better with a Canon 30D modified with the Baader ACF filter?\u003c\/h3\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion-A\"\u003e\n\u003cp\u003eYou will see the most significant improvement on \u003cstrong\u003eemission nebulae\u003c\/strong\u003e rich in Hydrogen-alpha. Expect stunning results on targets such as:\u003c\/p\u003e\n\u003cul\u003e\n\u003cli\u003eThe Orion Nebula (M42)\u003c\/li\u003e\n\u003cli\u003eThe Lagoon Nebula (M8)\u003c\/li\u003e\n\u003cli\u003eThe North American Nebula (NGC 7000)\u003c\/li\u003e\n\u003cli\u003eThe California Nebula (NGC 1499)\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion\"\u003e\n\u003ch3 class=\"DAV-accordion-Q\"\u003eIs the installation of the Baader ACF DSLR Astro Conversion Filter reversible?\u003c\/h3\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion-A\"\u003e\n\u003cp\u003eThe modification requires careful disassembly of your DSLR. While it is technically possible to reverse the process if you save the original filter, it is a delicate and complex procedure that carries a significant risk of damaging the camera. For this reason, it is generally considered a \u003cstrong\u003epermanent modification\u003c\/strong\u003e.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion\"\u003e\n\u003ch3 class=\"DAV-accordion-Q\"\u003eWhat does \"plane optically polished\" mean for the Baader ACF filter?\u003c\/h3\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion-A\"\u003e\n\u003cp\u003eIt means the filter's surfaces are manufactured to be extremely flat and perfectly parallel to each other. This is a critical quality feature that \u003cstrong\u003eprevents image degradation\u003c\/strong\u003e. It ensures the filter will not introduce any distortions or blur, preserving the full sharpness and resolution of your optical system.\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\u003eDSLR Astro Conversion Filter (ACF)\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eCompatible Cameras\u003c\/td\u003e\n\u003ctd\u003eCanon EOS 350D, 10D, 20D, 30D\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003ePrimary Purpose\u003c\/td\u003e\n\u003ctd\u003eIncreases Hydrogen-Alpha (Hα) Sensitivity\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eOptical Quality\u003c\/td\u003e\n\u003ctd\u003ePlane-Optically Polished\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eFilter size\u003c\/td\u003e\n\u003ctd\u003eother\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eFilter shape\u003c\/td\u003e\n\u003ctd\u003erectangular\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eSingle or Set?\u003c\/td\u003e\n\u003ctd\u003eSingle Filter\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eFilter mounted\u003c\/td\u003e\n\u003ctd\u003eUnmounted\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eFilter Usage\u003c\/td\u003e\n\u003ctd\u003eColor Correction, H-alpha, IR-Cut, UV-Cut\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eTransmission Range\u003c\/td\u003e\n\u003ctd\u003e400 – 700 nm\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eAR-Coating\u003c\/td\u003e\n\u003ctd\u003edielectrically coated, planeoptically polished\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\"\u003eBaader ACF DSLR Astro Conversion 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\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_Filter_Problems_FAQ_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 Filter Problems FAQ Manual\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":44967355908381,"sku":"BAA-2459212","price":139.0,"currency_code":"CAD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0753\/5280\/1565\/products\/Baader-ACF-DSLR-Astro-Conversion-Filter-for-Canon-EOS-350D-10D-20D-30D-1__90920.1597110899.1280.1280.jpg?v=1684340982"},{"product_id":"baader-bcf-dslr-astro-conversion-filter-for-canon-eos","title":"Baader BCF DSLR Astro Conversion Filter - for Canon EOS","description":"\u003cul class=\"DAV-feature-list\"\u003e\n\u003cli\u003eReplaces stock DSLR filter to dramatically increase H-alpha sensitivity\u003c\/li\u003e\n\u003cli\u003eEnables detailed imaging of emission nebulae\u003c\/li\u003e\n\u003cli\u003eDesigned for a wide range of Canon EOS APS-C cameras\u003c\/li\u003e\n\u003cli\u003eMaintains correct focus with standard camera lenses\u003c\/li\u003e\n\u003cli\u003eA permanent modification for dedicated astrophotography use\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 BCF DSLR Astro Conversion Filter - for Canon EOS\u003c\/h2\u003e\n\u003cp\u003eThe Baader BCF DSLR Astro Conversion Filter replaces the stock IR-cut filter in Canon EOS models like the 7D, 40D, and 50D, dramatically increasing their sensitivity to the critical Hydrogen-alpha wavelength. This modification is essential for capturing the faint, red structures in emission nebulae like the North American Nebula (NGC 7000) that a standard DSLR sensor cannot record. It transforms compatible cameras, including the 60D, 600D, and 1100D, into capable deep-sky imaging instruments.\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\u003eUnlocking Hydrogen-Alpha for Deep-Sky Imaging\u003c\/h3\u003e\n\u003cp\u003eA standard DSLR camera is engineered for daytime photography, which requires filtering out the infrared and ultraviolet light that human eyes don't see. Unfortunately, this stock filter also blocks most of the deep-red Hydrogen-alpha light that is the primary emission from the most iconic nebulae. The Baader BCF is specifically designed to replace this restrictive filter, opening a new window for your camera's sensor.\u003c\/p\u003e\n\u003cp\u003eBy installing the BCF, you allow this crucial wavelength to reach the sensor, revealing the intricate details, faint extensions, and true color of targets like the Orion Nebula (M42) and the Lagoon Nebula (M8). This is not a subtle change; it is the fundamental step in converting a consumer camera into a serious astrophotography tool.\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\u003eCompatibility for Canon EOS 7D, 40D, 50D, 60D, and More\u003c\/h3\u003e\n\u003cp\u003eThis Baader BCF filter is engineered for a precise fit within the sensor assemblies of a wide range of popular Canon EOS DSLR bodies. It is a direct replacement for the original filter, ensuring that autofocus and infinity focus with standard camera lenses are maintained after the conversion.\u003c\/p\u003e\n\u003cul\u003e\n\u003cli\u003e\n\u003cstrong\u003eSupported Models:\u003c\/strong\u003e Canon EOS 7D, 40D, 50D, 60D, 400D, 450D, 500D, 550D, 600D, 650D, 1000D, and 1100D.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eInstallation Note:\u003c\/strong\u003e Replacing the internal filter is a delicate, irreversible process that requires disassembling the camera body. This modification should only be undertaken if you are comfortable with intricate electronics work or by a professional service.\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\u003eThe Astro-Conversion Advantage: Baader BCF vs. a Stock DSLR Filter\u003c\/h3\u003e\n\u003cp\u003eThe difference between an image taken with a stock DSLR and one with a Baader BCF-modified camera is night and day, especially on emission nebulae. A stock camera will struggle to record anything more than the brightest core of a nebula, often with weak, muddy colors. The modified camera captures the full extent of the object's glowing hydrogen gas.\u003c\/p\u003e\n\u003cp\u003eWhile a dedicated astronomy camera offers cooling and monochrome capabilities, a modified DSLR is a powerful and cost-effective entry into serious deep-sky imaging. The Baader BCF provides the most critical part of that conversion: enhanced red sensitivity. After modification, your camera will still function for daytime use, but will require a custom white balance to correct the color cast.\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 benefit of installing the Baader BCF in my Canon EOS camera?\u003c\/h3\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion-A\"\u003e\n\u003cp\u003eThe primary benefit is a massive increase in sensitivity to the \u003cstrong\u003eHydrogen-alpha wavelength\u003c\/strong\u003e. This allows your Canon DSLR to capture the faint, red light from emission nebulae, which is almost completely blocked by the camera's stock filter, transforming it into a powerful tool for deep-sky astrophotography.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion\"\u003e\n\u003ch3 class=\"DAV-accordion-Q\"\u003eWill the Baader BCF filter allow my Canon 60D to photograph the Orion Nebula (M42) better?\u003c\/h3\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion-A\"\u003e\n\u003cp\u003eAbsolutely. The Orion Nebula (M42) is rich in Hydrogen-alpha emissions. A standard Canon 60D will only capture the bright, central Trapezium region well, while the extensive outer loops of gas will appear faint and lack detail. With the Baader BCF installed, your 60D will record the full, vibrant red structure of the entire nebula complex.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion\"\u003e\n\u003ch3 class=\"DAV-accordion-Q\"\u003eAfter installing the Baader BCF filter, can I still use my Canon 450D for normal daytime photography?\u003c\/h3\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion-A\"\u003e\n\u003cp\u003eYes, but with a critical adjustment. After the conversion, daytime images will have a strong red color cast. To correct this, you must shoot using a \u003cstrong\u003ecustom white balance\u003c\/strong\u003e setting. By taking a reference photo of a neutral gray or white card, you can create a white balance profile that produces natural-looking colors for terrestrial subjects.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion\"\u003e\n\u003ch3 class=\"DAV-accordion-Q\"\u003eIs the Baader BCF filter installation reversible?\u003c\/h3\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion-A\"\u003e\n\u003cp\u003eWhile technically possible, the process is not considered easily reversible. It involves delicate disassembly of the camera and sensor assembly. It is best to consider this a \u003cstrong\u003epermanent modification\u003c\/strong\u003e dedicated to converting the camera for astrophotography.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion\"\u003e\n\u003ch3 class=\"DAV-accordion-Q\"\u003eWhich Canon EOS models is the Baader BCF filter compatible with?\u003c\/h3\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion-A\"\u003e\n\u003cp\u003eThe Baader BCF is designed for a range of Canon APS-C sensor DSLRs. Compatible models include the \u003cstrong\u003eCanon EOS 7D, 40D, 50D, 60D, 400D, 450D, 500D, 550D, 600D, 650D, 1000D, and 1100D\u003c\/strong\u003e.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion\"\u003e\n\u003ch3 class=\"DAV-accordion-Q\"\u003eHow does a Baader BCF-modified Canon 7D compare to a dedicated astronomy camera for imaging the Heart Nebula (IC 1805)?\u003c\/h3\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion-A\"\u003e\n\u003cp\u003eA Baader BCF-modified Canon 7D will dramatically outperform a stock DSLR on the Heart Nebula (IC 1805), capturing its extensive H-alpha structures. However, a dedicated astronomy camera typically offers sensor cooling to reduce thermal noise during long exposures, which will result in a cleaner final image with better signal-to-noise ratio. The modified DSLR is a fantastic, cost-effective step up, while a cooled astro camera is the next level for ultimate image quality.\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 size\u003c\/td\u003e\n\u003ctd\u003eother\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eFilter shape\u003c\/td\u003e\n\u003ctd\u003erectangular\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eSingle or Set?\u003c\/td\u003e\n\u003ctd\u003eSingle Filter\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eFilter mounted\u003c\/td\u003e\n\u003ctd\u003eUnmounted\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eFilter Usage\u003c\/td\u003e\n\u003ctd\u003eColor Correction, H-alpha, IR-Cut, UV-Cut\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eTransmission Range\u003c\/td\u003e\n\u003ctd\u003e400 – 700 nm\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eAR-Coating\u003c\/td\u003e\n\u003ctd\u003edielectrically coated, planeoptically polished\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\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":44967355941149,"sku":"BAA-2459213","price":114.0,"currency_code":"CAD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0753\/5280\/1565\/products\/Baader-BCF-DSLR-Astro-Conversion-Filter-for-Canon-EOS-7D-40D-50D-60D-400D-450D-500D-550D-600D-650D-1000D-1100D-1__19322.1597110900.1280.1280.jpg?v=1684340985"},{"product_id":"baader-clear-focusing-filter","title":"Baader Clear Focusing Filter","description":"\u003cul class=\"DAV-feature-list\"\u003e\n\u003cli\u003eEnables precise focusing for dim narrowband filters\u003c\/li\u003e\n\u003cli\u003ePerfectly parfocal with other Baader Planetarium filters\u003c\/li\u003e\n\u003cli\u003eOptically polished to ensure no image degradation\u003c\/li\u003e\n\u003cli\u003eAvailable in multiple formats from 1.25\" mounted to 65x65mm square\u003c\/li\u003e\n\u003cli\u003eLPFC (Low Profile Filter Cell) on mounted versions for maximum compatibility\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 Clear Focusing Filter\u003c\/h2\u003e\n\u003cp\u003eThe Baader Clear Focusing Filter, available in multiple formats including 1.25\" and 2\" mounted cells and unmounted sizes up to 65x65mm, solves the most critical challenge of narrowband imaging: achieving perfect focus on a dim target. It is designed to be perfectly parfocal with Baader's line of imaging filters, allowing you to use a bright, full-spectrum star to achieve sharp focus before swapping to a restrictive line filter without any change in the focal point.\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 Parfocal Solution for Dim Narrowband Filters\u003c\/h3\u003e\n\u003cp\u003eNarrowband filters transmit such a tiny fraction of the visual spectrum that focusing can be an exercise in frustration. Stars become too faint for autofocus routines or to produce clear spikes on a Bahtinov mask. The Baader Clear Focusing Filter eliminates this problem by providing a bright, full-spectrum view for focusing.\u003c\/p\u003e\n\u003cp\u003eBecause this clear filter is manufactured to the exact same optical thickness as Baader's narrowband, LRGB, and other imaging filters, the focal plane does not shift when you switch between them. You can achieve critical focus once with the clear filter and be confident that every subsequent narrowband exposure is perfectly sharp, saving valuable time and eliminating wasted sub-exposures.\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\u003eOptically Polished Glass for Pinpoint Focus Accuracy\u003c\/h3\u003e\n\u003cp\u003eThis is not simply a blank piece of glass; it is a high-quality optical window. Each Baader Clear Focusing Filter is optically polished to maintain the integrity of your light path, ensuring that the focus you achieve is true and not compromised by optical imperfections. This prevents any degradation of your final image resolution.\u003c\/p\u003e\n\u003cp\u003eThe 1.25\" and 2\" mounted versions feature Baader's Low Profile Filter Cell (LPFC), designed to prevent vignetting and fit easily into any standard filter wheel or drawer. For users with specific needs, the filter is also available in a wide range of unmounted sizes, from 31mm round to 65x65mm square, to accommodate nearly any imaging setup.\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\"\u003eWhy do I need a Baader Clear Focusing Filter for narrowband imaging?\u003c\/h3\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion-A\"\u003e\n\u003cp\u003eNarrowband filters, like H-alpha or OIII, block almost all light, making stars extremely dim and difficult to focus on. The \u003cstrong\u003eBaader Clear Focusing Filter\u003c\/strong\u003e is parfocal (maintains the same focus point) with these filters. This allows you to focus on a bright star with a full-spectrum view, then swap to your narrowband filter without needing to refocus, ensuring perfect sharpness.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion\"\u003e\n\u003ch3 class=\"DAV-accordion-Q\"\u003eIs the Baader Clear Focusing Filter just an empty filter cell or blank glass?\u003c\/h3\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion-A\"\u003e\n\u003cp\u003eNo. It is a high-quality optical window that has been \u003cstrong\u003eoptically polished\u003c\/strong\u003e to a high standard. This ensures it does not introduce any distortion or aberrations into your optical train. Using a non-polished piece of glass would compromise the critical focus you are trying to achieve.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion\"\u003e\n\u003ch3 class=\"DAV-accordion-Q\"\u003eWill the Baader Clear Focusing Filter be parfocal with filters from other brands?\u003c\/h3\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion-A\"\u003e\n\u003cp\u003eNot necessarily. Parfocality depends on the precise mechanical thickness of the filter substrate. The \u003cstrong\u003eBaader Clear Focusing Filter\u003c\/strong\u003e is specifically designed to match the thickness of other Baader Planetarium filters. While it may be close with other brands, perfect parfocality is only guaranteed within the Baader system.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion\"\u003e\n\u003ch3 class=\"DAV-accordion-Q\"\u003eIf I'm imaging the Pelican Nebula (IC 5070) in SII, how does the Baader Clear Focusing Filter help?\u003c\/h3\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion-A\"\u003e\n\u003cp\u003eImaging the faint sulfur emissions of the Pelican Nebula requires long exposures through a very dim filter. Instead of struggling to focus on a faint star through the SII filter, you would use the \u003cstrong\u003eBaader Clear Focusing Filter\u003c\/strong\u003e to focus on a nearby bright star like Deneb. Once your focus is locked, you can swap to the SII filter in your filter wheel, slew to the nebula, and begin imaging, confident that your focus is perfect.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion\"\u003e\n\u003ch3 class=\"DAV-accordion-Q\"\u003eI use a filter drawer with a fast f\/4 Newtonian. Is the Baader Clear Focusing Filter still effective?\u003c\/h3\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion-A\"\u003e\n\u003cp\u003eYes, it is especially effective with fast systems. Fast optics have a very critical focus zone, making precise focus even more important. The \u003cstrong\u003eBaader Clear Focusing Filter\u003c\/strong\u003e allows you to use all available light to nail that critical focus point, which is extremely difficult to do with a dim narrowband filter at f\/4. The parfocal design ensures that focus is maintained when you insert your imaging filter.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion\"\u003e\n\u003ch3 class=\"DAV-accordion-Q\"\u003eWhich size of the Baader Clear Focusing Filter do I need?\u003c\/h3\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion-A\"\u003e\n\u003cp\u003eThe correct size depends on your filter wheel, filter drawer, or camera setup. The \u003cstrong\u003eBaader Clear Focusing Filter\u003c\/strong\u003e is available in several standard sizes:\u003c\/p\u003e\n\u003cul\u003e\n\u003cli\u003e\n\u003cstrong\u003e1.25\" and 2\" Mounted:\u003c\/strong\u003e For standard filter wheels and focusers that accept threaded filters.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003e31mm and 36mm Round Unmounted:\u003c\/strong\u003e Common sizes for 1.25\" filter wheels.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003e50.4mm Round, 50x50mm Square, and 65x65mm Square Unmounted:\u003c\/strong\u003e For larger filter wheels designed for full-frame and medium-format sensors.\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\u003eType\u003c\/td\u003e\n\u003ctd\u003eClear Focusing Filter\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eOptical Quality\u003c\/td\u003e\n\u003ctd\u003eOptically Polished\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003ePrimary Use\u003c\/td\u003e\n\u003ctd\u003eAchieving parfocal focus with narrowband and LRGB filters\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eAvailable Formats\u003c\/td\u003e\n\u003ctd\u003e1.25\" Round Mounted, 2\" Round Mounted, 31mm Round Unmounted, 36mm Round Unmounted, 50.4mm Round Unmounted, 50x50mm Square, 65x65mm Square\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eMounted Filter Cell\u003c\/td\u003e\n\u003ctd\u003eLow Profile Filter Cell (LPFC) on 1.25\" and 2\" versions\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eNet weight (kg)\u003c\/td\u003e\n\u003ctd\u003e0.01 (1.25\" Round Mounted, 2\" Round Mounted, 50.4mm Round Unmounted Filter)\u003cbr\u003e0.02 (50x50mm Square Filter)\u003cbr\u003e0.03 (65x65mm Square Filter)\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eFilter shape\u003c\/td\u003e\n\u003ctd\u003eround (1.25\" Round Mounted, 2\" Round Mounted, 31mm Round Unmounted Filter, 36mm Round Unmounted Filter, 50.4mm Round Unmounted Filter)\u003cbr\u003esquare (50x50mm Square Filter, 65x65mm Square Filter)\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eSingle or Set?\u003c\/td\u003e\n\u003ctd\u003eSingle Filter\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eFilter Usage\u003c\/td\u003e\n\u003ctd\u003eFocusing\/dust protection\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eFilter Thickness (without cell)\u003c\/td\u003e\n\u003ctd\u003e2 mm (1.25\" Round Mounted, 2\" Round Mounted, 31mm Round Unmounted Filter, 36mm Round Unmounted Filter)\u003cbr\u003e3 mm (50.4mm Round Unmounted Filter, 50x50mm Square Filter, 65x65mm Square Filter)\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eTransmission Range\u003c\/td\u003e\n\u003ctd\u003efull Spectrum\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eAR-Coating\u003c\/td\u003e\n\u003ctd\u003edielectrically coated, planeoptically polished\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eType of Filter\u003c\/td\u003e\n\u003ctd\u003eClearglass (31mm Round Unmounted Filter)\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\"\u003eBaader Clear Focusing Filter (select size)\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\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_Cleaning_and_Maintenance_of_Optics_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 Cleaning and Maintenance of Optics 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_Anti-Reflective_LRGBC_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 Anti-Reflective LRGBC 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":"1.25\" Round Mounted","offer_id":44967356039453,"sku":"BAA-2458415","price":63.0,"currency_code":"CAD","in_stock":true},{"title":"2\" Round Mounted","offer_id":44967356072221,"sku":"BAA-2458416","price":105.0,"currency_code":"CAD","in_stock":true},{"title":"31mm Round Unmounted Filter","offer_id":44967356104989,"sku":"BAA-2458414","price":78.0,"currency_code":"CAD","in_stock":true},{"title":"36mm Round Unmounted Filter","offer_id":44967356137757,"sku":"BAA-2459423","price":70.0,"currency_code":"CAD","in_stock":true},{"title":"50.4mm Round Unmounted Filter","offer_id":44967356170525,"sku":"BAA-2458420","price":121.0,"currency_code":"CAD","in_stock":true},{"title":"50x50mm Square Filter","offer_id":44967356203293,"sku":"BAA-2458421","price":140.0,"currency_code":"CAD","in_stock":true},{"title":"65x65mm Square Filter","offer_id":44967356236061,"sku":"BAA-2459405","price":152.0,"currency_code":"CAD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0753\/5280\/1565\/files\/Baader-Clear-Focusing-Filter-1__69249.1597110902.1280.1280.jpg?v=1684340987"},{"product_id":"baader-h-alpha-ccd-filter-35nm","title":"Baader H-Alpha CCD Filter -35nm","description":"\u003c!-- more --\u003e\u003cul\u003e\n\u003cli\u003ePremium grade H-alpha interline chip CCD-filter for fast optical systems f\/10 to f\/2.8\u003c\/li\u003e\n\u003cli\u003eIR-blocked\u003c\/li\u003e\n\u003cli\u003eNO halos, NO reflections, NO ghosting\u003c\/li\u003e\n\u003cli\u003eNon-aging sealed coating edges\u003c\/li\u003e\n\u003c\/ul\u003e\u003cp\u003eBaader's new H-Alpha passfilter enables high-contrast deep sky images of H-II regions (such as the N. American Nebula). Its medium 35nm FWHM bandwidth is ideal for interline CCD cameras ( like SBIG ST-2000\/STL11000). The lower sensitivity of interline transfer CCDs benefits from the more efficient 35nm FWHM. The sharp bandpass and \u0026gt; 90% high efficiency coatings make the Baader H-Alpha filter superior to the common colored-glass based filters, all at a reasonable price.\u003cbr\u003e\u003cbr\u003eThe Baader H-Alpha filter shares the same outstanding features as all the other Baader imaging filters. Unmatched optical quality, and high efficiency hardened multicoatings result in the sharpest and highest contrast images possible.\u003c\/p\u003e\u003cp\u003e\u003cimg alt=\"H-Alpha 35nm Transmission Curve\" src=\"https:\/\/cdn.shopify.com\/s\/files\/1\/0753\/5280\/1565\/t\/6\/assets\/description_image_h_alpha_ccd_35nm_curve_480x480.jpg?v=1684340632?v=1585244106\"\u003e\u003c\/p\u003e\u003cp\u003e\u003cstrong\u003eH-Alpha 35nm Transmission Curve\u003c\/strong\u003e\u003c\/p\u003e\u003cp\u003e\u003c\/p\u003e\u003cdiv data-custom-tab\u003e\n\u003cp data-custom-tab-title\u003eSpecifications\u003c\/p\u003e\n\u003cdiv\u003e\n\u003ch2\u003e1.25\"\u003c\/h2\u003e\n\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\u003e2458381\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003cth\u003eEAN CODE\u003c\/th\u003e\n\u003ctd\u003e4047825009456\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003cth\u003eWEIGHT (KG)\u003c\/th\u003e\n\u003ctd\u003e0.059\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003cth\u003eCOLOUR\u003c\/th\u003e\n\u003ctd\u003eBlack\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003cth\u003eTRANSMISSION RANGE\u003c\/th\u003e\n\u003ctd\u003eH-alpha\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003cth\u003eFILTER THICKNESS (WITHOUT CELL)\u003c\/th\u003e\n\u003ctd\u003e2 mm\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003cth\u003eHBW (HALFBANDWIDTH)\u003c\/th\u003e\n\u003ctd\u003e35nm\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003cth\u003eCWL (CENTRAL WAVELENGTH)\u003c\/th\u003e\n\u003ctd\u003e656,3 nm\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003cth\u003eAR-COATING\u003c\/th\u003e\n\u003ctd\u003edielectrically coated, planeoptically polished\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003cth\u003eFILTER SIZE\u003c\/th\u003e\n\u003ctd\u003e1 25 inch\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003cth\u003eFILTER USAGE\u003c\/th\u003e\n\u003ctd\u003eH-alpha, Interline-CCD, IR-Cut\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003cth\u003eFILTER MOUNTED\u003c\/th\u003e\n\u003ctd\u003eMounted (LPFC 6mm)\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003cth\u003eTYPE OF FILTER\u003c\/th\u003e\n\u003ctd\u003eNarrowband\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003cth\u003eSINGLE OR SET?\u003c\/th\u003e\n\u003ctd\u003eSingle Filter\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003cth\u003eFILTER SHAPE\u003c\/th\u003e\n\u003ctd\u003eround\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003c\/tbody\u003e\u003c\/table\u003e\n\u003ch2\u003e2\"\u003c\/h2\u003e\n\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\u003e2458380\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003cth\u003eEAN CODE\u003c\/th\u003e\n\u003ctd\u003e4047825009463\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003cth\u003eWEIGHT (KG)\u003c\/th\u003e\n\u003ctd\u003e0.066\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003cth\u003eCOLOUR\u003c\/th\u003e\n\u003ctd\u003eBlack\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003cth\u003eTRANSMISSION RANGE\u003c\/th\u003e\n\u003ctd\u003eH-alpha\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003cth\u003eFILTER THICKNESS (WITHOUT CELL)\u003c\/th\u003e\n\u003ctd\u003e2 mm\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003cth\u003eHBW (HALFBANDWIDTH)\u003c\/th\u003e\n\u003ctd\u003e35nm\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003cth\u003eCWL (CENTRAL WAVELENGTH)\u003c\/th\u003e\n\u003ctd\u003e656,3 nm\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003cth\u003eAR-COATING\u003c\/th\u003e\n\u003ctd\u003edielectrically coated, planeoptically polished\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003cth\u003eFILTER SIZE\u003c\/th\u003e\n\u003ctd\u003e2 inch\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003cth\u003eFILTER USAGE\u003c\/th\u003e\n\u003ctd\u003eH-alpha, Interline-CCD, IR-Cut\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003cth\u003eFILTER MOUNTED\u003c\/th\u003e\n\u003ctd\u003eMounted (LPFC 6mm)\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003cth\u003eTYPE OF FILTER\u003c\/th\u003e\n\u003ctd\u003eNarrowband\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003cth\u003eSINGLE OR SET?\u003c\/th\u003e\n\u003ctd\u003eSingle Filter\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003cth\u003eFILTER SHAPE\u003c\/th\u003e\n\u003ctd\u003eround\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003c\/tbody\u003e\u003c\/table\u003e\n\u003ch2\u003e50.8mm\u003c\/h2\u003e\n\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\u003e2458379\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003cth\u003eEAN CODE\u003c\/th\u003e\n\u003ctd\u003e4047825009470\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003cth\u003eWEIGHT (KG)\u003c\/th\u003e\n\u003ctd\u003e0.07\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003cth\u003eCOLOUR\u003c\/th\u003e\n\u003ctd\u003eBlack\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003cth\u003eTRANSMISSION RANGE\u003c\/th\u003e\n\u003ctd\u003eH-alpha\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003cth\u003eFILTER THICKNESS (WITHOUT CELL)\u003c\/th\u003e\n\u003ctd\u003e3 mm\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003cth\u003eHBW (HALFBANDWIDTH)\u003c\/th\u003e\n\u003ctd\u003e35nm\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003cth\u003eCWL (CENTRAL WAVELENGTH)\u003c\/th\u003e\n\u003ctd\u003e656,3 nm\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003cth\u003eAR-COATING\u003c\/th\u003e\n\u003ctd\u003edielectrically coated, planeoptically polished\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003cth\u003eFILTER SIZE\u003c\/th\u003e\n\u003ctd\u003e50.8 mm\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003cth\u003eFILTER USAGE\u003c\/th\u003e\n\u003ctd\u003eH-alpha, Interline-CCD, IR-Cut\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003cth\u003eFILTER MOUNTED\u003c\/th\u003e\n\u003ctd\u003eUnmounted\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003cth\u003eTYPE OF FILTER\u003c\/th\u003e\n\u003ctd\u003eNarrowband\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003cth\u003eSINGLE OR SET?\u003c\/th\u003e\n\u003ctd\u003eSingle Filter\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003cth\u003eFILTER SHAPE\u003c\/th\u003e\n\u003ctd\u003eround\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003c\/tbody\u003e\u003c\/table\u003e\n\u003ch2\u003e50x50mm\u003c\/h2\u003e\n\u003ctable\u003e\n\u003ccolgroup\u003e\n\u003ccol width=\"25%\"\u003e\n\u003ccol\u003e\n\u003c\/colgroup\u003e\n\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\u003e2458379R\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003cth\u003eEAN CODE\u003c\/th\u003e\n\u003ctd\u003e4047825022806\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003cth\u003eWEIGHT (KG)\u003c\/th\u003e\n\u003ctd\u003e0.074\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003cth\u003eTRANSMISSION RANGE\u003c\/th\u003e\n\u003ctd\u003eH-alpha\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003cth\u003eFILTER THICKNESS (WITHOUT CELL)\u003c\/th\u003e\n\u003ctd\u003e3 mm\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003cth\u003eHBW (HALFBANDWIDTH)\u003c\/th\u003e\n\u003ctd\u003e35nm\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003cth\u003eCWL (CENTRAL WAVELENGTH)\u003c\/th\u003e\n\u003ctd\u003e656,3 nm\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003cth\u003eAR-COATING\u003c\/th\u003e\n\u003ctd\u003edielectrically coated, planeoptically polished\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003cth\u003eFILTER SIZE\u003c\/th\u003e\n\u003ctd\u003e50 x 50 mm\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003cth\u003eFILTER USAGE\u003c\/th\u003e\n\u003ctd\u003eH-alpha, Interline-CCD, IR-Cut\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003cth\u003eFILTER MOUNTED\u003c\/th\u003e\n\u003ctd\u003eUnmounted\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003cth\u003eTYPE OF FILTER\u003c\/th\u003e\n\u003ctd\u003eNarrowband\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003cth\u003eSINGLE OR SET?\u003c\/th\u003e\n\u003ctd\u003eSingle Filter\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003cth\u003eFILTER SHAPE\u003c\/th\u003e\n\u003ctd\u003esquare\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003c\/tbody\u003e\n\u003c\/table\u003e\n\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_faq_problems_with_filters_can_have_the_strangest_causes.pdf?v=1684340622?v=1590138683\" target=\"_blank\"\u003eFAQ - Problems with filters can have the strangest causes\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_halos_no_problem.pdf?v=1684340636?v=1590141382\" target=\"_blank\"\u003eHalos - No Problem!\u003c\/a\u003e\u003c\/p\u003e\n\u003c\/div\u003e","brand":"Baader Planetarium","offers":[{"title":"1.25\" Round Mounted","offer_id":44967356629277,"sku":"BAA-2458381","price":153.0,"currency_code":"CAD","in_stock":true},{"title":"2\" Round Mounted","offer_id":44967356662045,"sku":"BAA-2458380","price":279.0,"currency_code":"CAD","in_stock":true},{"title":"50.4mm Round Unmounted Filter","offer_id":44967356694813,"sku":"BAA-2458379","price":300.0,"currency_code":"CAD","in_stock":true},{"title":"50x50mm Square Filter","offer_id":44967356727581,"sku":"BAA-2458379R","price":370.0,"currency_code":"CAD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0753\/5280\/1565\/files\/Baader-H-Alpha-CCD-Filter-35nm-1__30810.1597110905.1280.1280.jpg?v=1684341297"},{"product_id":"baader-6-5nm-f-2-highspeed-filter-set-cmos-optimized-h-alpha-o-iii-s-ii","title":"Baader 6.5nm f\/2  Highspeed Filter Set - CMOS-Optimized H-alpha\/O-III\/S-II","description":"\u003cul class=\"DAV-feature-list\"\u003e\n\u003cli\u003eSet of 3 Narrowband Filters: H-alpha, O-III, and S-II\u003c\/li\u003e\n\u003cli\u003e6.5nm Bandpass for high-contrast imaging\u003c\/li\u003e\n\u003cli\u003eOptimized for f\/2 to f\/3.5 High-Speed Optical Systems\u003c\/li\u003e\n\u003cli\u003ePre-shifted bandpass prevents signal loss from steep light cones\u003c\/li\u003e\n\u003cli\u003eCMOS-optimized with Reflex-Blocker™ coatings to eliminate halos\u003c\/li\u003e\n\u003cli\u003eSealed coating edges prevent moisture intrusion and aging\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 6.5nm f\/2 Highspeed Filter Set - CMOS-Optimized H-alpha\/O-III\/S-II\u003c\/h2\u003e\n\u003cp\u003eThe Baader 6.5nm f\/2 Highspeed Filter Set contains three essential narrowband filters (H-alpha, O-III, S-II) specifically engineered to maintain peak transmission when used with ultra-fast astrographs like Celestron RASA or Hyperstar systems. Standard narrowband filters suffer significant signal loss at focal ratios faster than f\/4, but this 6.5nm set is pre-shifted to perfectly align with the emission lines from an f\/2 light cone, ensuring maximum signal capture. This optimization allows modern CMOS sensors to record deep, high-contrast images of emission nebulae without the reflection halos or bandpass-shift issues that compromise data from fast optical systems.\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\u003eDesigned for f\/2 Systems: Pre-Shifted for Maximum Signal\u003c\/h3\u003e\n\u003cp\u003eIn a fast optical system, light rays approach the filter at a very steep angle, causing a phenomenon known as bandpass shift, where the filter's central wavelength shifts towards blue. A standard narrowband filter used at f\/2 can shift so much that it partially blocks the very emission line you're trying to capture. Baader's f\/2 Highspeed filters solve this by pre-shifting the central wavelength of the bandpass, ensuring that at f\/2, it is perfectly centered on the H-alpha, O-III, or S-II line for peak transmission.\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\u003eCMOS-Optimized for 6.5nm Signals: Halation and Reflection Control\u003c\/h3\u003e\n\u003cp\u003eModern CMOS sensors, while incredibly sensitive, are also highly reflective. When paired with traditional filters, this can create strong halos and internal reflections around bright stars. The Baader Highspeed filters incorporate advanced Reflex-Blocker™ coatings that are hardened and optimized to suppress these reflections, delivering clean stellar profiles. Additionally, the coating edges are sealed (Life-Coat™), making them exceptionally durable and resistant to degradation from moisture, ensuring their high transmission for years of use.\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\u003e6.5nm Bandpass: High Contrast for Emission Nebulae\u003c\/h3\u003e\n\u003cp\u003eThe 6.5nm full width at half maximum (FWHM) strikes a critical balance between contrast and signal acquisition speed. This bandpass is narrow enough to dramatically darken the sky background, isolating faint nebular structures from moonlight and urban light pollution. At the same time, it is wide enough to deliver a strong signal, which is crucial for capturing data efficiently with fast f\/2 optical systems where exposure times are already significantly reduced.\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 f\/2 Highspeed vs. Standard Narrowband Filters\u003c\/h3\u003e\n\u003cp\u003eThe choice between this f\/2 Highspeed set and a standard narrowband filter set comes down to your telescope's focal ratio.\n\u003c\/p\u003e\n\u003cul\u003e\n\u003cli\u003e\n\u003cstrong\u003eStandard Filters (f\/4 and slower):\u003c\/strong\u003e These filters are designed for the shallower light cones of most refractors, SCTs, and Newtonians. Using them on an f\/2 system results in significant signal loss due to bandpass shift.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eBaader f\/2 Highspeed Filters:\u003c\/strong\u003e These are purpose-built for systems from f\/2 to f\/3.5. Their pre-shifted design maximizes signal. Using them on a slower f\/8 telescope is a trade-off; the filter's center wavelength will be slightly offset from the emission line, resulting in a suboptimal, though still usable, signal.\u003c\/li\u003e\n\u003c\/ul\u003e\n\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 makes the Baader 6.5nm f\/2 Highspeed filters different from standard narrowband filters?\u003c\/h3\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion-A\"\u003e\n\u003cp\u003eThe key difference is their \u003cstrong\u003epre-shifted bandpass\u003c\/strong\u003e. Standard filters are designed for f\/4 or slower systems. When used at f\/2, the steep light cone shifts their transmission window, blocking part of the nebula's light. The Baader f\/2 Highspeed filters are manufactured to be perfectly on-band when used at f\/2, ensuring maximum signal throughput.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion\"\u003e\n\u003ch3 class=\"DAV-accordion-Q\"\u003eCan I use the Baader f\/2 filters on my f\/8 Ritchey-Chrétien telescope?\u003c\/h3\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion-A\"\u003e\n\u003cp\u003eWhile you can, it is not optimal. These filters are pre-shifted for an f\/2 light cone. On an f\/8 system, the filter's bandpass will be slightly blue-shifted relative to the target emission line, resulting in a small reduction in signal. For f\/8 systems, a standard narrowband filter designed for slower focal ratios will deliver better results.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion\"\u003e\n\u003ch3 class=\"DAV-accordion-Q\"\u003eWhat does \"CMOS-Optimized\" mean for the Baader Highspeed Filter Set?\u003c\/h3\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion-A\"\u003e\n\u003cp\u003eIt refers to the advanced \u003cstrong\u003eReflex-Blocker™ coatings\u003c\/strong\u003e applied to the filters. Modern CMOS sensors are very reflective, which can cause halos and artifacts around bright stars. These specialized coatings are designed to suppress these reflections, producing cleaner images with tighter star profiles, even on very bright targets.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion\"\u003e\n\u003ch3 class=\"DAV-accordion-Q\"\u003eHow will the 6.5nm Baader filters perform on the Horsehead Nebula (Barnard 33) with my RASA 8?\u003c\/h3\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion-A\"\u003e\n\u003cp\u003eThis filter set is an ideal match for imaging the Horsehead Nebula with a RASA 8. The f\/2 focal ratio of the RASA is exactly what these filters are designed for. The \u003cstrong\u003e6.5nm H-alpha filter\u003c\/strong\u003e will provide excellent contrast to define the dark nebula against the glowing background of IC 434, capturing sharp detail with very short exposure times.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion\"\u003e\n\u003ch3 class=\"DAV-accordion-Q\"\u003eAre these Baader f\/2 filters parfocal?\u003c\/h3\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion-A\"\u003e\n\u003cp\u003eYes, Baader Planetarium engineers their CMOS-optimized filters to be parfocal. When you switch between the H-alpha, O-III, and S-II filters in this set, you should see minimal to no change in focus, saving valuable imaging time by eliminating the need to refocus with each filter change.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion\"\u003e\n\u003ch3 class=\"DAV-accordion-Q\"\u003eWhy would I choose a 6.5nm bandpass over a narrower 3nm filter for my f\/2 system?\u003c\/h3\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion-A\"\u003e\n\u003cp\u003eFor an f\/2 system, a \u003cstrong\u003e6.5nm bandpass\u003c\/strong\u003e is often a better compromise. While a 3nm filter provides higher contrast, it's more sensitive to bandpass shift and collects photons more slowly. The 6.5nm width provides excellent contrast while maintaining a very high signal acquisition rate, which is the primary advantage of using an f\/2 astrograph.\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 Set\u003c\/td\u003e\n\u003ctd\u003eH-alpha, O-III, S-II\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eBandpass (FWHM)\u003c\/td\u003e\n\u003ctd\u003e6.5nm\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eOptimized Focal Ratio\u003c\/td\u003e\n\u003ctd\u003ef\/2 to f\/3.5\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eCoatings\u003c\/td\u003e\n\u003ctd\u003eReflex-Blocker™, Life-Coat™\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eCMOS Optimized\u003c\/td\u003e\n\u003ctd\u003eYes\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eAvailable Sizes\u003c\/td\u003e\n\u003ctd\u003e1.25\" Mounted, 2\" Mounted, 31mm Unmounted, 36mm Unmounted, 50.4mm Unmounted, 50x50mm Unmounted, 65x65mm Unmounted\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eNet weight (kg)\u003c\/td\u003e\n\u003ctd\u003e0.02 (1.25\" Round Mounted)\u003cbr\u003e0.04 (2\" Round Mounted, 50.4mm Round Unmounted Filter)\u003cbr\u003e0.01 (31mm Round Unmounted Filter, 36mm Round Unmounted Filter)\u003cbr\u003e0.06 (50x50mm Square Filter)\u003cbr\u003e0.10 (65x65mm Square Filter)\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eFilter shape\u003c\/td\u003e\n\u003ctd\u003eround (1.25\" Round Mounted, 2\" Round Mounted, 31mm Round Unmounted Filter, 50.4mm Round Unmounted Filter, 36mm Round Unmounted Filter)\u003cbr\u003esquare (50x50mm Square Filter, 65x65mm Square Filter)\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eFilter mounted\u003c\/td\u003e\n\u003ctd\u003eMounted (LPFC 6mm) (1.25\" Round Mounted, 2\" Round Mounted)\u003cbr\u003eUnmounted (31mm Round Unmounted Filter, 50.4mm Round Unmounted Filter, 50x50mm Square Filter, 36mm Round Unmounted Filter, 65x65mm Square Filter)\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eFilter Usage\u003c\/td\u003e\n\u003ctd\u003eCMOS, CCD, H-alpha, O-III, S-II\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eSpecial Features\u003c\/td\u003e\n\u003ctd\u003eCMOS-optimized with Life-Coat™\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eFilter Thickness (without cell)\u003c\/td\u003e\n\u003ctd\u003e2 mm (1.25\" Round Mounted, 2\" Round Mounted, 31mm Round Unmounted Filter, 36mm Round Unmounted Filter)\u003cbr\u003e3 mm (50.4mm Round Unmounted Filter, 50x50mm Square Filter, 65x65mm Square Filter)\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eCWL (Central Wavelength)\u003c\/td\u003e\n\u003ctd\u003e656.3 nm \/ 500.7 nm \/ 671.7 nm\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eAR-Coating\u003c\/td\u003e\n\u003ctd\u003eReflex-Blocker™ hard coated, planeoptically polished\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eSuitable for f\/ratio\u003c\/td\u003e\n\u003ctd\u003ef\/3.4 and faster\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\u003cdiv class=\"DAV-section-center\"\u003e\n\u003cp\u003e\u003cem\u003eNote: This is a filter set containing three individual filters. Box contents may vary based on the specific size selected.\u003c\/em\u003e\u003c\/p\u003e\n\u003c\/div\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_Filter_Problems_FAQ_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 Filter Problems FAQ 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_Narrowband_Filters_on_Astronomical_Telescopes_Whitepaper.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 Narrowband Filters on Astronomical Telescopes Whitepaper\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":"1.25\" Round Mounted","offer_id":44967356989725,"sku":"BAA-2961660","price":656.0,"currency_code":"CAD","in_stock":true},{"title":"2\" Round Mounted","offer_id":44967357022493,"sku":"BAA-2961663","price":1079.0,"currency_code":"CAD","in_stock":true},{"title":"31mm Round Unmounted Filter","offer_id":44967357055261,"sku":"BAA-2961661","price":696.0,"currency_code":"CAD","in_stock":true},{"title":"50.4mm Round Unmounted Filter","offer_id":44967357088029,"sku":"BAA-2961664","price":1127.0,"currency_code":"CAD","in_stock":true},{"title":"50x50mm Square Filter","offer_id":44967357153565,"sku":"BAA-2961665","price":1298.0,"currency_code":"CAD","in_stock":true},{"title":"36mm Round Unmounted Filter","offer_id":44967357186333,"sku":"BAA-2961662","price":775.0,"currency_code":"CAD","in_stock":true},{"title":"65x65mm Square Filter","offer_id":44967357219101,"sku":"BAA-2961666","price":1611.0,"currency_code":"CAD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0753\/5280\/1565\/files\/Baader-f-2-Highspeed-Filter-Set-H-alpha-O-III-S-II-1__52568.1597110925.1280.1280.jpg?v=1684341313"},{"product_id":"baader-ir-pass-filter-685nm","title":"Baader IR-Pass Filter 685nm","description":"\u003cul class=\"DAV-feature-list\"\u003e\n\u003cli\u003e685nm Infrared (IR) Pass Filter\u003c\/li\u003e\n\u003cli\u003eTransmits deep-red light starting from 670nm\u003c\/li\u003e\n\u003cli\u003eDramatically reduces the image-blurring effects of atmospheric seeing\u003c\/li\u003e\n\u003cli\u003eIdeal for high-resolution planetary, lunar, and solar imaging\u003c\/li\u003e\n\u003cli\u003eServes as a superior Luminance (L) filter for LRGB composites\u003c\/li\u003e\n\u003cli\u003eFeatures reflex-free anti-reflection coatings on an optically polished substrate\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 IR-Pass Filter 685nm\u003c\/h2\u003e\n\u003cp\u003eThe Baader IR-Pass Filter 685nm isolates the deep-red and near-infrared spectrum, transmitting light that starts from 670nm. By blocking the shorter wavelengths of the conventional 400-700nm visual spectrum, this filter bypasses the worst of atmospheric turbulence, allowing planetary imagers to capture significantly sharper details that would otherwise be blurred by poor seeing.\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\u003eDefeating Atmospheric Turbulence with Light Beyond 685nm\u003c\/h3\u003e\n\u003cp\u003eAtmospheric seeing, the shimmering effect caused by air turbulence, is the primary obstacle to high-resolution imaging. Longer wavelengths of light are less susceptible to this distortion. The Baader 685nm IR-Pass filter exploits this physical principle by creating an image using only light from the most stable part of the spectrum, rendering dark structures on Mars, Jupiter, the Moon, and the Sun with much higher contrast and sharpness.\u003c\/p\u003e\n\u003cp\u003eBecause the filter's transmission begins at 670nm, it sits just at the edge of the visual range. This allows you to achieve focus with a sensitive camera before capturing the final, stabilized image in the near-infrared—a crucial advantage over deeper IR filters that are completely opaque to the human eye.\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\u003eLRGB Imaging: Creating a Superior Luminance Channel with the 685nm Filter\u003c\/h3\u003e\n\u003cp\u003eFor imagers using the LRGB (Luminance, Red, Green, Blue) method, the Baader 685nm IR-Pass serves as an exceptional luminance filter. On nights of unsteady seeing, capturing the 'L' channel through this filter ensures your image's foundational detail layer is as sharp as possible. This high-resolution monochrome data can then be combined with standard RGB data to produce a final color image that possesses far greater detail than one shot with a traditional broadband luminance filter.\u003c\/p\u003e\n\u003cul\u003e\n\u003cli\u003e\n\u003cstrong\u003eOptically Polished Substrate:\u003c\/strong\u003e Ensures the filter does not introduce any degradation to the optical path, preserving the performance of your telescope.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eAnti-Reflection Coatings:\u003c\/strong\u003e Both sides of the filter are treated with reflex-free anti-reflection coatings to maximize light transmission and prevent internal reflections from causing halos or ghosting on bright targets.\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 use the Baader 685nm IR-Pass filter instead of a regular Luminance filter?\u003c\/h3\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion-A\"\u003e\n\u003cp\u003eA regular Luminance filter passes the entire visible spectrum (roughly 400-700nm), making it susceptible to atmospheric turbulence (seeing). The \u003cstrong\u003eBaader 685nm IR-Pass filter\u003c\/strong\u003e rejects these shorter, more easily scattered wavelengths, producing a much sharper, higher-contrast image that serves as a superior detail layer in an LRGB composite, especially on nights with poor seeing.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion\"\u003e\n\u003ch3 class=\"DAV-accordion-Q\"\u003eCan I see through the Baader 685nm IR-Pass filter to focus?\u003c\/h3\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion-A\"\u003e\n\u003cp\u003eBarely. The filter begins transmitting at 670nm, which is at the very edge of human vision in the deep red. While you won't see much detail, a bright star or planet may be visible enough to aid in focusing, especially on a sensitive monochrome camera's live view. It is significantly easier to focus with than deeper IR-pass filters (like 742nm or 850nm) which are completely opaque.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion\"\u003e\n\u003ch3 class=\"DAV-accordion-Q\"\u003eWhat kind of camera works best with the Baader 685nm IR-Pass filter?\u003c\/h3\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion-A\"\u003e\n\u003cp\u003eA \u003cstrong\u003emonochrome CMOS or CCD camera\u003c\/strong\u003e is highly recommended. These cameras typically have much higher quantum efficiency in the near-infrared spectrum compared to one-shot color cameras, allowing for shorter exposures and better signal-to-noise ratio when using the Baader 685nm IR-Pass filter.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion\"\u003e\n\u003ch3 class=\"DAV-accordion-Q\"\u003eHow will the Baader 685nm IR-Pass filter improve my images of Jupiter with an 8\" SCT?\u003c\/h3\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion-A\"\u003e\n\u003cp\u003eAn 8\" SCT has enough aperture to resolve fine detail on Jupiter, but this is often limited by seeing. The \u003cstrong\u003eBaader 685nm IR-Pass filter\u003c\/strong\u003e will help stabilize the image, allowing you to capture sharper details in the cloud bands, the Great Red Spot, and smaller storms. By using it as your luminance channel, your final LRGB image of Jupiter will appear much more detailed than what you could capture with a standard UV\/IR cut filter alone.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion\"\u003e\n\u003ch3 class=\"DAV-accordion-Q\"\u003eIs the Baader 685nm IR-Pass filter useful for solar imaging of sunspots?\u003c\/h3\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion-A\"\u003e\n\u003cp\u003eYes, absolutely. When used with a proper, full-aperture solar film or glass filter, the \u003cstrong\u003eBaader 685nm IR-Pass filter\u003c\/strong\u003e acts as a powerful seeing-reduction tool for white-light solar imaging. It will increase the contrast and sharpness of sunspot umbra\/penumbra details and solar granulation by minimizing atmospheric blurring.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion\"\u003e\n\u003ch3 class=\"DAV-accordion-Q\"\u003eDo I still need RGB filters if I use the Baader 685nm IR-Pass filter?\u003c\/h3\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion-A\"\u003e\n\u003cp\u003eYes. The image from the Baader 685nm IR-Pass filter is monochrome and only captures detail, not color. To create a full-color image, you must capture separate data using Red, Green, and Blue filters and then combine them with the high-resolution data from the IR-Pass filter in post-processing software.\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\u003eInfrared (IR) Pass\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eCenter Wavelength\u003c\/td\u003e\n\u003ctd\u003e685nm\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eCut-on Wavelength\u003c\/td\u003e\n\u003ctd\u003eStarts transmitting at ~670nm\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003ePrimary Use\u003c\/td\u003e\n\u003ctd\u003eHigh-Resolution Planetary, Lunar, Solar Imaging\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eCoatings\u003c\/td\u003e\n\u003ctd\u003eReflex-free anti-reflective\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eSubstrate\u003c\/td\u003e\n\u003ctd\u003eOptically Polished\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eAvailable Sizes\u003c\/td\u003e\n\u003ctd\u003e1.25\" and 2\" Mounted\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eNet weight (kg)\u003c\/td\u003e\n\u003ctd\u003e0.01\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eFilter shape\u003c\/td\u003e\n\u003ctd\u003eround\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eSingle or Set?\u003c\/td\u003e\n\u003ctd\u003eSingle Filter\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eFilter mounted\u003c\/td\u003e\n\u003ctd\u003eMounted (LPFC 6mm)\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eFilter Usage\u003c\/td\u003e\n\u003ctd\u003eContrast Enhancement, IR-Pass, Planetary\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eFilter Thickness (without cell)\u003c\/td\u003e\n\u003ctd\u003e2 mm\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eAR-Coating\u003c\/td\u003e\n\u003ctd\u003edielectrically coated, planeoptically polished\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\"\u003eBaader IR-Pass Filter 685nm (Selected Size)\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\"\u003ePlastic Filter Case\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\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_Filter_Problems_FAQ_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 Filter Problems FAQ Manual\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":"1.25\" Round Mounted","offer_id":44967357645085,"sku":"BAA-2458385","price":132.0,"currency_code":"CAD","in_stock":true},{"title":"2\" Round Mounted","offer_id":44967357677853,"sku":"BAA-2458386","price":209.0,"currency_code":"CAD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0753\/5280\/1565\/products\/Baader-IR-Pass-Filter-685nm-1__95154.1597110927.1280.1280.jpg?v=1684341019"},{"product_id":"baader-methane-filter-889nm-8nm-1-25","title":"Baader Methane Filter 889nm - 8nm 1.25\"","description":"\u003cul class=\"DAV-feature-list\"\u003e\n\u003cli\u003e889nm Center Wavelength\u003c\/li\u003e\n\u003cli\u003e8nm Bandwidth (FWHM)\u003c\/li\u003e\n\u003cli\u003eTargets Methane Absorption Band\u003c\/li\u003e\n\u003cli\u003eHigh-Contrast Planetary Imaging\u003c\/li\u003e\n\u003cli\u003e1.25\" Filter 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\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 Methane Filter 889nm - 8nm 1.25\"\u003c\/h2\u003e\n\u003cp\u003eThe Baader Methane Filter isolates a narrow 8nm bandpass centered at 889nm, a specific near-infrared wavelength designed for 1.25\" filter wheels to reveal high-altitude structures in the methane-rich atmospheres of Jupiter and Saturn. This filter transforms your view of gas giants from a simple color image into a scientific tool, creating high-contrast monochrome data that highlights features invisible in the visible spectrum.\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\u003ePlanetary Science: Imaging Jupiter and Saturn in the 889nm Methane Band\u003c\/h3\u003e\n\u003cp\u003eThe 889nm wavelength is significant because it corresponds to a strong methane absorption band. When you image a gas giant through this filter, the deep atmospheric layers rich in methane gas absorb this light and appear dark. Conversely, high-altitude clouds, storms, and hazes that sit above the main methane layer reflect sunlight and appear brilliantly bright, creating a stark, high-contrast image.\u003c\/p\u003e\n\u003cp\u003eOn Jupiter, this effect makes the Equatorial Zone and the Great Red Spot (GRS) stand out with dramatic clarity. For Saturn, you can capture details in its banded structure and detect seasonal polar storms that are otherwise washed out by the planet's muted visible-light appearance. This is not just a different view; it's a method for mapping the vertical structure of a planet's atmosphere.\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\u003eImaging Technique: The Demands of an 8nm Near-Infrared Bandpass\u003c\/h3\u003e\n\u003cp\u003eUsing the Baader Methane Filter requires a specific approach. Because it isolates a tight 8nm bandpass in the near-infrared—where silicon sensors are less sensitive—you will need longer exposure times or higher gain settings than with a standard luminance or IR-pass filter. This makes the filter best suited for telescopes with larger apertures that can gather sufficient light.\u003c\/p\u003e\n\u003cul\u003e\n\u003cli\u003e\n\u003cstrong\u003eMonochrome Camera Required:\u003c\/strong\u003e This is a scientific filter designed for use with a monochrome astronomy camera to capture a detailed luminance layer. A color camera's Bayer matrix would block most of the incoming light and produce a very weak, unusable signal.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eSeeing is Critical:\u003c\/strong\u003e The longer required exposures make this filter sensitive to atmospheric turbulence. For the best results, you should use it on nights of good to excellent seeing to resolve the fine details it's capable of revealing.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eData Integration:\u003c\/strong\u003e The methane-band image is typically captured as a separate channel and can be colorized with RGB data to create a final composite that shows both the scientific detail from the 889nm band and the natural color of the planet.\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\"\u003eHow will the Baader Methane Filter make Jupiter's Great Red Spot appear?\u003c\/h3\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion-A\"\u003e\n\u003cp\u003eJupiter's Great Red Spot (GRS) is a high-altitude storm system. Because it sits above much of the planet's atmospheric methane, it will reflect sunlight at 889nm and appear very bright through the \u003cstrong\u003eBaader Methane Filter\u003c\/strong\u003e, standing out in high contrast against the darker, methane-absorbing cloud belts surrounding it.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion\"\u003e\n\u003ch3 class=\"DAV-accordion-Q\"\u003eCan I use the Baader Methane Filter with a color camera?\u003c\/h3\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion-A\"\u003e\n\u003cp\u003eNo, this filter is not recommended for color cameras. The \u003cstrong\u003eBaader Methane Filter\u003c\/strong\u003e isolates a very narrow 8nm band of near-infrared light at 889nm. A color camera's Bayer matrix would block approximately 75% of this already-dim signal, resulting in extremely low efficiency and poor image quality. A monochrome camera is required.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion\"\u003e\n\u003ch3 class=\"DAV-accordion-Q\"\u003eWhy is the Baader Methane Filter centered on the 889nm wavelength?\u003c\/h3\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion-A\"\u003e\n\u003cp\u003eThe 889nm wavelength corresponds to a strong absorption line for methane gas. By imaging specifically at this wavelength, the \u003cstrong\u003eBaader Methane Filter\u003c\/strong\u003e allows astronomers to differentiate between deep, methane-rich atmospheric layers (which appear dark) and high-altitude features like clouds and storms (which appear bright).\u003c\/p\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion\"\u003e\n\u003ch3 class=\"DAV-accordion-Q\"\u003eWhat kind of telescope works best with the Baader Methane Filter?\u003c\/h3\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion-A\"\u003e\n\u003cp\u003eBecause the filter has a narrow 8nm bandpass in the near-IR, it passes a limited amount of light. For this reason, the \u003cstrong\u003eBaader Methane Filter\u003c\/strong\u003e performs best with larger aperture telescopes (typically 8\" or more) that have greater light-gathering power. This helps to keep exposure times manageable and achieve a better signal-to-noise ratio.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion\"\u003e\n\u003ch3 class=\"DAV-accordion-Q\"\u003eWhat is the purpose of the narrow 8nm bandpass on the Baader Methane Filter?\u003c\/h3\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion-A\"\u003e\n\u003cp\u003eThe narrow 8nm bandpass ensures that only light from the specific methane absorption band is recorded. This precision increases contrast by rejecting adjacent infrared wavelengths, darkening the methane-rich areas more effectively and making the high-altitude features stand out more sharply.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion\"\u003e\n\u003ch3 class=\"DAV-accordion-Q\"\u003eWill the Baader Methane Filter help with imaging Mars or the Moon?\u003c\/h3\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion-A\"\u003e\n\u003cp\u003eNo, this filter is highly specialized for the methane-rich atmospheres of gas giants like Jupiter and Saturn. Mars has a very thin atmosphere with negligible methane, and the Moon has no atmosphere at all. Using the \u003cstrong\u003eBaader Methane Filter\u003c\/strong\u003e on these targets would only produce a very dim, low-contrast infrared image with no scientific benefit.\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\u003eBandpass\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eCenter Wavelength\u003c\/td\u003e\n\u003ctd\u003e889nm\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eBandwidth (FWHM)\u003c\/td\u003e\n\u003ctd\u003e8nm\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eSize\u003c\/td\u003e\n\u003ctd\u003e1.25\"\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003ePrimary Application\u003c\/td\u003e\n\u003ctd\u003ePlanetary Imaging (Gas Giants)\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eNet weight (kg)\u003c\/td\u003e\n\u003ctd\u003e0.01\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eFilter shape\u003c\/td\u003e\n\u003ctd\u003eround\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eSingle or Set?\u003c\/td\u003e\n\u003ctd\u003eSingle Filter\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eFilter mounted\u003c\/td\u003e\n\u003ctd\u003eMounted (LPFC 6mm)\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eFilter Usage\u003c\/td\u003e\n\u003ctd\u003eCCD, Planetary, Specialty\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eFilter Thickness (without cell)\u003c\/td\u003e\n\u003ctd\u003e2 mm\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eTransmission Range\u003c\/td\u003e\n\u003ctd\u003eMethan\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eAR-Coating\u003c\/td\u003e\n\u003ctd\u003edielectrically coated, planeoptically polished\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\"\u003eBaader Methane Filter 889nm - 8nm 1.25\"\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\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_Cleaning_and_Maintenance_of_Optics_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 Cleaning and Maintenance of Optics Manual\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":44967357776157,"sku":"BAA-2458295","price":348.0,"currency_code":"CAD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0753\/5280\/1565\/products\/Baader-Methane-Filter-889nm-8nm-1-25-inch-1__14885.1597110939.1280.1280.jpg?v=1684341026"},{"product_id":"baader-6-5nm-narrowband-filter-set-cmos-optimized-h-alpha-o-iii-s-ii","title":"Baader 6.5nm Narrowband Filter Set - CMOS-Optimized H-alpha\/O-III\/S-II","description":"\u003cul class=\"DAV-feature-list\"\u003e\n\u003cli\u003e6.5nm Narrowband Filter Set for H-alpha, O-III, and S-II\u003c\/li\u003e\n\u003cli\u003eOptimized specifically for modern CMOS astronomy cameras\u003c\/li\u003e\n\u003cli\u003eReflex-Blocker™ coatings prevent halos and internal reflections\u003c\/li\u003e\n\u003cli\u003eLife-Coat™ sealed edges for enhanced durability and longevity\u003c\/li\u003e\n\u003cli\u003ePlaneoptically polished substrates ensure maximum image sharpness\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 6.5nm Narrowband Filter Set - CMOS-Optimized H-alpha\/O-III\/S-II\u003c\/h2\u003e\n\u003cp\u003eThe Baader 6.5nm Narrowband Filter Set is engineered for modern CMOS sensors, combining a tight 6.5nm bandpass with advanced coatings to isolate critical H-alpha, O-III, and S-II emission lines without generating artifacts. This 6.5nm design delivers high-contrast images by aggressively rejecting light pollution and moonlight, while the CMOS-optimization eliminates the halos around bright stars that plague filters not designed for highly reflective modern sensors.\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\u003eCMOS-Optimized Coatings: Suppressing Halos and Reflections\u003c\/h3\u003e\n\u003cp\u003eModern CMOS sensors are notoriously reflective compared to older CCD technology. Baader addresses this directly with advanced Reflex-Blocker™ coatings, which are specifically designed to neutralize reflections between the filter and the sensor. This technology effectively eliminates the halos and ghost images that can ruin an otherwise perfect exposure, even with very bright stars like Alnitak in the field of view.\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 6.5nm Bandpass: High Contrast for Nebula Imaging\u003c\/h3\u003e\n\u003cp\u003eThe 6.5nm full width at half maximum (FWHM) strikes a critical balance between contrast and signal strength. This bandpass is narrow enough to darken the sky background significantly and enhance faint nebular details, yet it remains efficient enough for use with a wide range of telescope focal ratios. It provides a substantial contrast boost over wider 7nm or 12nm filters without requiring the extremely long sub-exposures demanded by ultra-narrow 3nm designs.\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\u003eUncompromised Substrate and Life-Coat Durability\u003c\/h3\u003e\n\u003cp\u003eEach Baader filter is built on a planeoptically polished substrate, ensuring that it will not degrade the resolution of your optical system. The coatings are applied with Ion-Beam-Assisted Deposition (IBAD), resulting in a hard, scratch-resistant surface. Furthermore, Baader's proprietary Life-Coat™ process seals the coating edges, making them impervious to moisture and aging, guaranteeing the filter's transmission properties will not degrade over time.\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 6.5nm CMOS vs. Traditional Narrowband Filters\u003c\/h3\u003e\n\u003cp\u003eOlder narrowband filters were designed for the less-reflective surfaces of CCD sensors. When used with a modern CMOS camera, these filters can produce prominent halos and reflections that are difficult to process out. The Baader CMOS-Optimized set solves this problem at the source.\u003c\/p\u003e\n\u003cul\u003e\n\u003cli\u003e\n\u003cstrong\u003eBaader 6.5nm CMOS-Optimized:\u003c\/strong\u003e Features Reflex-Blocker™ coatings to absorb reflections between the filter and sensor, producing clean, halo-free stars. The coatings are also shifted to remain on-band even with fast optical systems down to f\/3.5.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eTraditional Narrowband Filters:\u003c\/strong\u003e Lack specialized anti-reflection coatings for the camera side, leading to artifacts with reflective CMOS sensors. Their passbands can also shift significantly with fast focal ratios, reducing signal.\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 are these Baader 6.5nm filters \"CMOS-Optimized\"?\u003c\/h3\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion-A\"\u003e\n\u003cp\u003eThey are \"CMOS-Optimized\" because they feature Baader's proprietary \u003cstrong\u003eReflex-Blocker™ coatings\u003c\/strong\u003e. These coatings are specifically designed to prevent halos and internal reflections caused by the highly reflective nature of modern CMOS sensor assemblies. This results in cleaner images with higher contrast and no distracting artifacts around bright stars.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion\"\u003e\n\u003ch3 class=\"DAV-accordion-Q\"\u003eWhat is the advantage of a 6.5nm bandpass over a wider 7nm or 12nm filter?\u003c\/h3\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion-A\"\u003e\n\u003cp\u003eA narrower bandpass like \u003cstrong\u003e6.5nm\u003c\/strong\u003e provides significantly higher contrast by rejecting more unwanted light from streetlights, moonlight, and natural skyglow. This makes faint nebula structures stand out more clearly against the background sky compared to wider filters.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion\"\u003e\n\u003ch3 class=\"DAV-accordion-Q\"\u003eHow will the Baader 6.5nm O-III filter perform on the Veil Nebula (NGC 6960) with a fast refractor?\u003c\/h3\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion-A\"\u003e\n\u003cp\u003eExcellent. The Veil Nebula is a strong O-III emitter, and the \u003cstrong\u003e6.5nm\u003c\/strong\u003e bandpass will produce extremely high contrast, revealing the delicate, filamentary structure of the supernova remnant. Baader's coatings are also designed to minimize band-shift with fast optics, ensuring you capture maximum signal even with a fast refractor.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion\"\u003e\n\u003ch3 class=\"DAV-accordion-Q\"\u003eAre the filters in the Baader 6.5nm Narrowband Set parfocal?\u003c\/h3\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion-A\"\u003e\n\u003cp\u003eYes, Baader manufactures these filters to be parfocal. All filters in the set are made with the same substrate thickness, meaning you should not need to refocus, or will only need a minimal adjustment, when switching between the H-alpha, O-III, and S-II filters. This is a major time-saver for automated imaging runs.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion\"\u003e\n\u003ch3 class=\"DAV-accordion-Q\"\u003eI'm imaging the Heart Nebula (IC 1805) with my SCT at f\/7. Is 6.5nm a good choice?\u003c\/h3\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion-A\"\u003e\n\u003cp\u003eYes, \u003cstrong\u003e6.5nm\u003c\/strong\u003e is an excellent choice for an f\/7 system. The Heart Nebula is rich in all three emission lines (H-alpha, O-III, and S-II). The 6.5nm bandpass will provide the contrast needed to separate the intricate structures within the nebula, and an f\/7 optical system is efficient enough to gather plenty of signal without requiring excessively long sub-exposures.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion\"\u003e\n\u003ch3 class=\"DAV-accordion-Q\"\u003eCan I use the Baader 6.5nm H-alpha filter for solar viewing or imaging?\u003c\/h3\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion-A\"\u003e\n\u003cp\u003e\u003cstrong\u003eAbsolutely not.\u003c\/strong\u003e These are deep-sky emission-line filters and are not safe for any kind of solar observation. Attempting to view the sun through this filter will cause immediate and permanent eye damage. For solar work, you must use a dedicated, certified solar filter designed for that purpose.\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\u003eNarrowband Emission Line (SHO)\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eBandpass (FWHM)\u003c\/td\u003e\n\u003ctd\u003e6.5nm\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eWavelengths\u003c\/td\u003e\n\u003ctd\u003eH-alpha, O-III, S-II\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003ePrimary Feature\u003c\/td\u003e\n\u003ctd\u003eCMOS-Optimized with Reflex-Blocker™ Coatings\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eDurability\u003c\/td\u003e\n\u003ctd\u003eLife-Coat™ Sealed Coating Edges\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eAvailable Formats\u003c\/td\u003e\n\u003ctd\u003e1.25\" Mounted, 2\" Mounted, 31mm Unmounted, 36mm Unmounted, 50.4mm Unmounted, 50x50mm Square, 65x65mm Square\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eNet weight (kg)\u003c\/td\u003e\n\u003ctd\u003e0.02 (1.25\" Round Mounted)\u003cbr\u003e0.04 (2\" Round Mounted, 50.4mm Round Unmounted Filter)\u003cbr\u003e0.01 (36mm Round Unmounted Filter, 31mm Round Unmounted Filter)\u003cbr\u003e0.06 (50x50mm Square Filter)\u003cbr\u003e0.10 (65x65mm Square Filter)\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eFilter shape\u003c\/td\u003e\n\u003ctd\u003eround (1.25\" Round Mounted, 2\" Round Mounted, 36mm Round Unmounted Filter, 50.4mm Round Unmounted Filter, 31mm Round Unmounted Filter)\u003cbr\u003esquare (50x50mm Square Filter, 65x65mm Square Filter)\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eSingle or Set?\u003c\/td\u003e\n\u003ctd\u003eFilter-Set\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eFilter mounted\u003c\/td\u003e\n\u003ctd\u003eMounted (LPFC 6mm) (1.25\" Round Mounted, 2\" Round Mounted)\u003cbr\u003eUnmounted (36mm Round Unmounted Filter, 50.4mm Round Unmounted Filter, 50x50mm Square Filter, 65x65mm Square Filter, 31mm Round Unmounted Filter)\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eFilter Usage\u003c\/td\u003e\n\u003ctd\u003eCMOS, CCD, H-alpha, O-III, S-II\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eSpecial Features\u003c\/td\u003e\n\u003ctd\u003eCMOS-optimized with Life-Coat™\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eFilter Thickness (without cell)\u003c\/td\u003e\n\u003ctd\u003e2 mm (1.25\" Round Mounted, 2\" Round Mounted, 36mm Round Unmounted Filter, 31mm Round Unmounted Filter)\u003cbr\u003e3 mm (50.4mm Round Unmounted Filter, 50x50mm Square Filter, 65x65mm Square Filter)\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eCWL (Central Wavelength)\u003c\/td\u003e\n\u003ctd\u003e656.3 nm \/ 500.7 nm \/ 671.7 nm\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eAR-Coating\u003c\/td\u003e\n\u003ctd\u003eReflex-Blocker™ hard coated, planeoptically polished\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eSuitable for f\/ratio\u003c\/td\u003e\n\u003ctd\u003e\u0026gt; f\/3.4\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_Filter_Problems_FAQ_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 Filter Problems FAQ 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_Narrowband_Filters_on_Astronomical_Telescopes_Whitepaper.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 Narrowband Filters on Astronomical Telescopes Whitepaper\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":"1.25\" Round Mounted","offer_id":44967357808925,"sku":"BAA-2961650","price":609.0,"currency_code":"CAD","in_stock":true},{"title":"2\" Round Mounted","offer_id":44967357841693,"sku":"BAA-2961653","price":1031.0,"currency_code":"CAD","in_stock":true},{"title":"36mm Round Unmounted Filter","offer_id":44967357874461,"sku":"BAA-2961652","price":728.0,"currency_code":"CAD","in_stock":true},{"title":"50.4mm Round Unmounted Filter","offer_id":44967357907229,"sku":"BAA-2961654","price":1174.0,"currency_code":"CAD","in_stock":true},{"title":"50x50mm Square Filter","offer_id":44967357939997,"sku":"BAA-2961655","price":1251.0,"currency_code":"CAD","in_stock":true},{"title":"65x65mm Square Filter","offer_id":44967357972765,"sku":"BAA-2961656","price":1589.0,"currency_code":"CAD","in_stock":true},{"title":"31mm Round Unmounted Filter","offer_id":44967358005533,"sku":"BAA-2961651","price":643.0,"currency_code":"CAD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0753\/5280\/1565\/products\/Baader-Narrowband-Filter-Set-H-a-7nm-OIII-8-5nm-SII-8nm-1__77412.1597110943.1280.1280.jpg?v=1684341339"}],"url":"https:\/\/davidastro.com\/collections\/filters.oembed?page=10","provider":"David Astro","version":"1.0","type":"link"}