{"product_id":"optolong-oiii-6-5nm-narrowband-filter","title":"Optolong OIII 6.5nm Narrowband Filter","description":"\u003cul class=\"DAV-feature-list\"\u003e\n\u003cli\u003e6.5nm Narrowband OIII Filter\u003c\/li\u003e\n\u003cli\u003eCentered on 500nm Wavelength\u003c\/li\u003e\n\u003cli\u003eCaptures both 495.9nm and 500.7nm Emission Lines\u003c\/li\u003e\n\u003cli\u003eBlocks Light Pollution and Skyglow\u003c\/li\u003e\n\u003cli\u003eIdeal for SHO Hubble Palette Imaging\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\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 OIII 6.5nm Narrowband Filter\u003c\/h2\u003e\n      \u003cp\u003eThe Optolong OIII 6.5nm Narrowband Filter isolates the critical emission lines of doubly-ionized oxygen by passing only a 6.5nm bandpass of light centered at a wavelength of 500nm. This extremely narrow window is engineered to capture both the 495.9nm and 500.7nm OIII lines, which are characteristic of planetary nebulae and supernova remnants, while aggressively rejecting unwanted light pollution and atmospheric skyglow.\u003c\/p\u003e\n    \u003c\/div\u003e\n  \u003c\/div\u003e\n\n  \u003cdiv class=\"DAV-bg-light\"\u003e\n    \u003cdiv class=\"DAV-section\"\u003e\n      \u003ch3\u003eA 6.5nm Bandpass for High-Contrast OIII Imaging\u003c\/h3\u003e\n      \u003cp\u003eBy restricting the incoming light to a tight 6.5nm window, this filter dramatically increases the contrast between your target nebula and the background sky. The filter doesn't make the nebula brighter; it darkens the sky around it, causing the faint, blue-green structural details of OIII-rich objects to stand out with striking clarity. This is essential for revealing the delicate shells of planetary nebulae or the shock fronts in supernova remnants.\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\u003eRejecting Skyglow by Targeting the 500nm Wavelength\u003c\/h3\u003e\n      \u003cp\u003eThe filter's transmission is precisely centered at 500nm to align with the OIII emission lines. Its primary function is to block out common sources of light pollution, including mercury-vapor and sodium-vapor streetlights, as well as the natural skyglow caused by neutral oxygen emission in the atmosphere. This targeted rejection allows for deep-sky imaging even under moonlit or urban sky conditions.\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\u003eBuilding the Hubble Palette: The \"O\" in SHO Imaging\u003c\/h3\u003e\n      \u003cp\u003eFor astrophotographers, the Optolong OIII 6.5nm filter is a cornerstone of narrowband imaging. It represents the \"O\" in the \"SHO\" Hubble Palette, where it is combined with Hydrogen-alpha and Sulphur-II filters. This technique allows you to create false-color images with stunning detail and color separation, revealing scientific information about the chemical composition of targets like the Pillars of Creation in the Eagle Nebula (M16).\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\u003eIon-Assisted Coatings for Wavelength Stability\u003c\/h3\u003e\n      \u003cp\u003eOptolong utilizes an ion-assisted deposition coating process to ensure the filter's durability and optical precision. This advanced technique produces a hard, scratch-resistant surface and guarantees the central wavelength (CWL) remains stable, with no deviation due to temperature changes during an imaging session. This consistency is critical for maintaining sharp focus and reliable data acquisition over long exposures.\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 purpose of the Optolong OIII 6.5nm filter?\u003c\/h3\u003e\n  \u003c\/div\u003e\n  \u003cdiv class=\"DAV-accordion-A\"\u003e\n    \u003cp\u003eThe Optolong OIII 6.5nm filter is designed to isolate the light emitted by doubly-ionized oxygen (OIII) from astronomical objects. Its narrow \u003cstrong\u003e6.5nm bandpass\u003c\/strong\u003e dramatically increases contrast by blocking light pollution and natural skyglow, making it ideal for imaging faint emission nebulae, planetary nebulae, and supernova remnants.\u003c\/p\u003e\n  \u003c\/div\u003e\n  \u003cdiv class=\"DAV-accordion\"\u003e\n    \u003ch3 class=\"DAV-accordion-Q\"\u003eWill the Optolong OIII 6.5nm filter make nebulae appear brighter?\u003c\/h3\u003e\n  \u003c\/div\u003e\n  \u003cdiv class=\"DAV-accordion-A\"\u003e\n    \u003cp\u003eNo, narrowband filters do not increase an object's brightness. Instead, the Optolong OIII 6.5nm filter increases the \u003cstrong\u003econtrast\u003c\/strong\u003e between the nebula and the night sky. By selectively blocking out all light except the specific 500nm OIII wavelength, it makes the background sky much darker, which in turn makes the nebula's structure far more visible.\u003c\/p\u003e\n  \u003c\/div\u003e\n    \u003cdiv class=\"DAV-accordion\"\u003e\n    \u003ch3 class=\"DAV-accordion-Q\"\u003eHow does the Optolong OIII 6.5nm filter fit into a SHO (Hubble Palette) imaging setup?\u003c\/h3\u003e\n  \u003c\/div\u003e\n  \u003cdiv class=\"DAV-accordion-A\"\u003e\n    \u003cp\u003eThe Optolong OIII 6.5nm filter is the \"O\" component in a standard SHO narrowband imaging set. Data captured with this filter is typically mapped to the green channel in image processing, alongside data from Hydrogen-alpha (red channel) and Sulphur-II (blue channel) filters. This combination creates the iconic, high-detail false-color images popularized by the Hubble Space Telescope.\u003c\/p\u003e\n  \u003c\/div\u003e\n    \u003cdiv class=\"DAV-accordion\"\u003e\n    \u003ch3 class=\"DAV-accordion-Q\"\u003eHow would the Optolong OIII 6.5nm filter perform on the Rosette Nebula (Caldwell 49) from a city?\u003c\/h3\u003e\n  \u003c\/div\u003e\n  \u003cdiv class=\"DAV-accordion-A\"\u003e\n    \u003cp\u003eThe Rosette Nebula is rich in both Hydrogen-alpha and Oxygen-III. From a light-polluted city, the Optolong OIII 6.5nm filter would be essential for capturing the delicate structures within the nebula's central region. It would effectively cut through the urban skyglow, allowing you to record the faint OIII signal that would otherwise be completely washed out, revealing details in the excavated core of the nebula.\u003c\/p\u003e\n  \u003c\/div\u003e\n    \u003cdiv class=\"DAV-accordion\"\u003e\n    \u003ch3 class=\"DAV-accordion-Q\"\u003eIs the Optolong OIII 6.5nm filter necessary for imaging the Pillars of Creation (M16)?\u003c\/h3\u003e\n  \u003c\/div\u003e\n  \u003cdiv class=\"DAV-accordion-A\"\u003e\n    \u003cp\u003eYes, it is a critical component for creating a classic Hubble Palette image of M16. While the pillars themselves are dense with Hydrogen-alpha and Sulphur-II, the surrounding nebulosity and the glowing edges of the pillars are illuminated by the intense radiation from young stars, causing them to emit strongly in OIII light. The Optolong OIII 6.5nm filter is required to capture this data and create the famous color separation and depth.\u003c\/p\u003e\n  \u003c\/div\u003e\n    \u003cdiv class=\"DAV-accordion\"\u003e\n    \u003ch3 class=\"DAV-accordion-Q\"\u003eDoes the Optolong OIII 6.5nm filter work with both monochrome and color cameras?\u003c\/h3\u003e\n  \u003c\/div\u003e\n  \u003cdiv class=\"DAV-accordion-A\"\u003e\n    \u003cp\u003eThis filter is designed primarily for use with \u003cstrong\u003emonochrome\u003c\/strong\u003e astronomy cameras. A monochrome sensor's higher sensitivity can take full advantage of the isolated wavelength. While it can be used with a one-shot-color (OSC) camera, the camera's Bayer matrix will only allow the blue and green pixels to detect the OIII signal, significantly reducing efficiency and resolution.\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\u003eAvailable Options\u003c\/td\u003e\n\u003ctd\u003e1.25\" Mounted, 2\" Mounted, 36mm Round Unmounted\u003c\/td\u003e\n\u003c\/tr\u003e\n    \u003c\/tbody\u003e\n  \u003c\/table\u003e\n\u003c\/li\u003e\n\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":52941918765341,"sku":"OPT-11501","price":223.0,"currency_code":"CAD","in_stock":true},{"title":"2\" Mounted","offer_id":52941918798109,"sku":"OPT-11502","price":321.0,"currency_code":"CAD","in_stock":true},{"title":"36mm Round Unmounted","offer_id":52941918830877,"sku":"OPT-11504","price":265.0,"currency_code":"CAD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0753\/5280\/1565\/files\/Optolong-improved-OIII6-5nm-narrowband-filter-1_8f87788c-6f04-4840-9bab-e49eeb58426d.jpg?v=1789592379","url":"https:\/\/davidastro.com\/fr\/products\/optolong-oiii-6-5nm-narrowband-filter","provider":"David Astro","version":"1.0","type":"link"}