{"product_id":"optolong-h-alpha-7nm-sii-6-5nm-oiii-6-5nm-filter-set-3-pcs","title":"Optolong Ha 7nm, OIII 6.5nm \u0026 SII 6.5nm Filter Set","description":"\u003cul class=\"DAV-feature-list\"\u003e\n\u003cli\u003e\n\u003cstrong\u003eH-alpha Filter:\u003c\/strong\u003e 7nm Bandpass centered at 656nm\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eOxygen-III Filter:\u003c\/strong\u003e 6.5nm Bandpass centered at 500nm\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eSulphur-II Filter:\u003c\/strong\u003e 6.5nm Bandpass\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eHubble Palette Ready:\u003c\/strong\u003e Complete SHO set for tri-band narrowband imaging\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eFormat Options:\u003c\/strong\u003e Available in 1.25\" Mounted, 2\" Mounted, or 36mm Unmounted versions\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\u003eOptolong Ha 7nm, OIII 6.5nm \u0026amp; SII 6.5nm Filter Set\u003c\/h2\u003e\n\u003cp\u003eThe Optolong Ha 7nm, OIII 6.5nm \u0026amp; SII 6.5nm Filter Set provides the three essential filters for creating high-contrast Hubble Palette images from light-polluted skies. This trio isolates the key emission lines from nebulae—Hydrogen-alpha at 656nm, Oxygen-III at 500nm, and Sulphur-II—with tight 7nm and 6.5nm bandpasses that reject unwanted skyglow and artificial light sources.\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 Hubble Palette: 6.5nm\/7nm Tri-Band Narrowband Imaging\u003c\/h3\u003e\n\u003cp\u003eThis filter set is engineered specifically for SHO imaging, where data from the Sulphur-II, Hydrogen-alpha, and Oxygen-III filters are mapped to the red, green, and blue channels of a final image. This technique, made famous by the Hubble Space Telescope, reveals incredible structural detail and color separation in emission nebulae like the Rosette Nebula (Caldwell 49) that are impossible to capture in broadband.\u003c\/p\u003e\n\u003cp\u003eDesigned for use with monochrome astronomy cameras or modified DSLRs, each filter isolates a specific emission line, allowing you to capture deep, high-contrast data one channel at a time, even under a bright moon or from a city 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\u003ePrecision Bandpasses: 7nm Ha, 6.5nm OIII, and 6.5nm SII\u003c\/h3\u003e\n\u003cp\u003eThe effectiveness of a narrowband filter is defined by its bandpass—the narrower, the better the contrast. The 7nm Ha filter captures the dominant 656nm wavelength present in nearly all emission nebulae. The even tighter 6.5nm bandpasses on the OIII and SII filters aggressively reject light pollution and background star signal, making faint nebular structures stand out dramatically.\u003c\/p\u003e\n\u003cul\u003e\n\u003cli\u003e\n\u003cstrong\u003eH-Alpha (7nm):\u003c\/strong\u003e Reveals the foundational hydrogen structure of nebulae with maximum signal.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eOIII (6.5nm):\u003c\/strong\u003e Isolates the 500nm blue-green light characteristic of planetary nebulae and supernova remnants, providing crucial detail and color contrast.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eSII (6.5nm):\u003c\/strong\u003e Captures the deep red light from ionized sulfur, often tracing shock fronts and dense regions that differ from the Ha data.\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\u003eAdvanced Coatings for 1.25\", 2\", and 36mm Formats\u003c\/h3\u003e\n\u003cp\u003eOptolong utilizes an advanced ion-assisted deposition coating process across all filter sizes, ensuring durability and scratch resistance. This technology also provides a stable central wavelength (CWL) that does not drift with temperature changes during an imaging session, preventing signal loss.\u003c\/p\u003e\n\u003cp\u003eThis meticulous manufacturing process results in excellent transmission at the target wavelengths and high optical density outside the passband. The coatings are engineered to significantly reduce halos around bright stars, a common issue in narrowband imaging, particularly noticeable in the improved OIII filter performance.\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\u003eOptolong 6.5nm\/7nm SHO Set vs. Wider Narrowband Filters\u003c\/h3\u003e\n\u003cp\u003eWhile wider filters, such as 12nm variants, can be a more forgiving starting point, the Optolong 6.5nm\/7nm set offers a significant step up in imaging capability. The primary advantage of the tighter bandpass is superior contrast and the ability to resolve finer nebular details.\u003c\/p\u003e\n\u003cp\u003eThe trade-off is that these filters require longer individual sub-exposure times to gather the same amount of signal as a wider filter. However, because they reject so much more background noise, the final integrated image achieves a much higher signal-to-noise ratio, producing cleaner, sharper, and more detailed results from any location.\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 \"Hubble Palette\" and why do I need this Optolong SHO filter set for it?\u003c\/h3\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion-A\"\u003e\n\u003cp\u003eThe \"Hubble Palette\" is an imaging technique where narrowband data is mapped to RGB channels to create false-color images with dramatic detail and contrast. This \u003cstrong\u003eOptolong SHO set\u003c\/strong\u003e provides the three required filters: Sulphur-II (mapped to Red), Hydrogen-alpha (Green), and Oxygen-III (Blue), allowing you to produce these iconic images.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion\"\u003e\n\u003ch3 class=\"DAV-accordion-Q\"\u003eCan I use the Optolong Ha 7nm, OIII 6.5nm \u0026amp; SII 6.5nm filters with my color camera?\u003c\/h3\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion-A\"\u003e\n\u003cp\u003eWhile technically possible, it is highly inefficient. These filters are designed for \u003cstrong\u003emonochrome cameras\u003c\/strong\u003e. A color camera's Bayer matrix blocks roughly 2\/3 of the incoming light for any given filter, requiring much longer exposures and producing lower-quality results. For color cameras, a multi-bandpass filter (like the L-eNhance or L-eXtreme) is a better choice.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion\"\u003e\n\u003ch3 class=\"DAV-accordion-Q\"\u003eHow will the Optolong 6.5nm OIII filter perform on the Orion Nebula (M42) from my city backyard?\u003c\/h3\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion-A\"\u003e\n\u003cp\u003eThe \u003cstrong\u003eOptolong 6.5nm OIII filter\u003c\/strong\u003e will excel on the Orion Nebula (M42) from a light-polluted location. Its tight 6.5nm bandpass will darken the sky background significantly, dramatically increasing the contrast of the delicate, wispy structures in the nebula's core and outer regions, which are rich in Oxygen-III emissions.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion\"\u003e\n\u003ch3 class=\"DAV-accordion-Q\"\u003eWhat's the main benefit of using the Optolong 7nm Ha filter on the Rosette Nebula (Caldwell 49) with my monochrome camera?\u003c\/h3\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion-A\"\u003e\n\u003cp\u003eThe primary benefit is immense contrast. The Rosette Nebula (Caldwell 49) is a massive cloud of hydrogen. The \u003cstrong\u003eOptolong 7nm Ha filter\u003c\/strong\u003e isolates its dominant 656nm emission line, rejecting moonlight, skyglow, and broadband light from stars. This allows your monochrome camera to record deep, detailed structural information of the nebula itself, separate from the background.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion\"\u003e\n\u003ch3 class=\"DAV-accordion-Q\"\u003eWhy is the Ha filter in this Optolong set 7nm while the OIII and SII are 6.5nm?\u003c\/h3\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion-A\"\u003e\n\u003cp\u003eHydrogen-alpha is typically the strongest signal in most emission nebulae. The slightly wider \u003cstrong\u003e7nm bandpass\u003c\/strong\u003e for the Ha filter ensures maximum signal capture for this critical channel. The OIII and SII signals are often weaker, so the tighter \u003cstrong\u003e6.5nm bandpass\u003c\/strong\u003e is used to maximize contrast by more aggressively rejecting background light pollution and skyglow, improving the signal-to-noise ratio for these fainter details.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion\"\u003e\n\u003ch3 class=\"DAV-accordion-Q\"\u003eDo these Optolong narrowband filters require longer exposure times than LRGB filters?\u003c\/h3\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion-A\"\u003e\n\u003cp\u003eYes, significantly longer. LRGB filters have very wide bandpasses to capture as much light as possible. The \u003cstrong\u003eOptolong narrowband filters\u003c\/strong\u003e in this set have extremely narrow 6.5nm and 7nm bandpasses. While this is key to their high-contrast performance, it means individual sub-exposures must be much longer (typically 3-10 minutes or more) to achieve a strong 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 Set\u003c\/td\u003e\n\u003ctd\u003eH-alpha, OIII, SII\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eH-Alpha Bandpass\u003c\/td\u003e\n\u003ctd\u003e7nm\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eH-Alpha Central Wavelength\u003c\/td\u003e\n\u003ctd\u003e656nm\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eOIII Bandpass\u003c\/td\u003e\n\u003ctd\u003e6.5nm\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eOIII Central Wavelength\u003c\/td\u003e\n\u003ctd\u003e500nm\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eSII Bandpass\u003c\/td\u003e\n\u003ctd\u003e6.5nm\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eAvailable Sizes\u003c\/td\u003e\n\u003ctd\u003e1.25\" Mounted, 2\" Mounted, 36mm Round Unmounted\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eCoating Technology\u003c\/td\u003e\n\u003ctd\u003eIon-assisted deposition\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\"\u003eH-Alpha 7nm Filter\u003c\/p\u003e\n\u003cp class=\"DAV-item-subtitle\"\u003e× 1\u003c\/p\u003e\n\u003c\/div\u003e\n\u003c\/li\u003e\n\u003cli class=\"DAV-grid-item\"\u003e\n\u003cdiv\u003e\n\u003cp class=\"DAV-item-title\"\u003eOIII 6.5nm Filter\u003c\/p\u003e\n\u003cp class=\"DAV-item-subtitle\"\u003e× 1\u003c\/p\u003e\n\u003c\/div\u003e\n\u003c\/li\u003e\n\u003cli class=\"DAV-grid-item\"\u003e\n\u003cdiv\u003e\n\u003cp class=\"DAV-item-title\"\u003eSII 6.5nm 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\u003ca href=\"https:\/\/davidastro.com\/pages\/optolong-warranty-policy\" rel=\"noopener\" target=\"_blank\"\u003eOptolong 3-Year Warranty\u003c\/a\u003e\n\u003c\/li\u003e\n\u003c\/ul\u003e","brand":"Optolong","offers":[{"title":"1.25\" Mounted","offer_id":52941930594589,"sku":"OPT-SHO-1.25","price":651.0,"currency_code":"CAD","in_stock":true},{"title":"2\" Mounted","offer_id":52941930627357,"sku":"OPT-SHO-2","price":937.0,"currency_code":"CAD","in_stock":true},{"title":"36mm Round Unmounted","offer_id":52941930660125,"sku":"OPT-SHO-RD36","price":769.0,"currency_code":"CAD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0753\/5280\/1565\/files\/Optolong-improved-NB-filters-SHO6-5nm-narrowband-filter-Kit-1_30b6be85-daea-48f5-b858-b12bd65e15c7.jpg?v=1789592457","url":"https:\/\/davidastro.com\/fr\/products\/optolong-h-alpha-7nm-sii-6-5nm-oiii-6-5nm-filter-set-3-pcs","provider":"David Astro","version":"1.0","type":"link"}