{"product_id":"antlia-3nm-narrowband-h-alpha-pro-highspeed-filter","title":"Antlia 3nm Narrowband H-alpha Pro Highspeed Filter - f\/2.6 to f\/3.6","description":"\u003cul\u003e\n\u003cli\u003ePre-shifted 656.3nm H-alpha Central Wavelength for High-Speed Systems\u003c\/li\u003e\n\u003cli\u003eOptimized 3nm FHWM for f\/2.6–f\/3.6\u003c\/li\u003e\n\u003cli\u003eHigh \u0026gt;90% Peak Transmission\u003c\/li\u003e\n\u003cli\u003eEnhanced SNR for Fast Optical Systems\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\u003eSpecifications\u003c\/li\u003e\n\u003cli\u003eIn the Box\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003cul class=\"tabs-content\"\u003e\n\u003cli class=\"active\"\u003e\n\u003cp\u003eIntroducing the Antlia 3nm H-Alpha Pro Highspeed Filter, specifically engineered for ultra-fast optical systems. This enhanced version is pre-shifted to compensate for the natural blue shift that occurs in fast focal ratio telescopes. By offsetting the central wavelength toward the red end of the spectrum, the filter maintains optimal signal capture in systems operating between f\/2.6 and f\/3.6, delivering significantly improved signal-to-noise ratio compared to standard 3nm filters.\u003c\/p\u003e\n\u003cp\u003eIn high-speed imaging systems, the converging light cone increases the angle of incidence (AOI), causing interference filters to shift toward shorter wavelengths. At f\/2.6, this shift can reach up to 2.2nm. The Antlia 3nm Pro Highspeed filter is precisely pre-shifted by 1.2nm to counteract this effect, ensuring maximum transmission at the critical 656.3nm hydrogen-alpha emission line during real-world use. With peak transmission exceeding 90% and a true 3nm bandwidth, this filter maximizes contrast while preserving faint nebular detail.\u003c\/p\u003e\n\u003ch3\u003eFeatures\u003c\/h3\u003e\n\u003cul\u003e\n\u003cli\u003e\n\u003cstrong\u003ePre-Shifted Spectral Design\u003c\/strong\u003e: Compensates for blue shift in fast systems, maintaining optimal signal accuracy.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eHigh-Speed Optimization\u003c\/strong\u003e: Designed specifically for focal ratios between f\/2.6 and f\/3.6 with minimal signal loss.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eImproved Sharp Cut-Off\u003c\/strong\u003e: Advanced coating design minimizes halos around bright stars while maintaining high contrast.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eExceptional Blocking\u003c\/strong\u003e: OD5 (0.001%) out-of-band blocking across 300–1000nm ensures excellent signal-to-noise ratio.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eSingle Substrate Construction\u003c\/strong\u003e: Non-glued optical substrate eliminates internal reflections for cleaner images.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eVersatile Application\u003c\/strong\u003e: Ideal for imaging emission nebulae, planetary nebulae, Wolf-Rayet nebulae, and supernova remnants in both light-polluted and dark-sky locations. Extends productive imaging time even under moonlit conditions.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eEdge Blackening\u003c\/strong\u003e: All unmounted Highspeed filters feature blackened edges to suppress stray light reflections.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eOptical Precision\u003c\/strong\u003e: Manufactured with strict quality standards to reduce post-processing and enhance reliability.\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003cp\u003ePlease note that the Antlia 3nm H-Alpha Pro Highspeed filter is specifically optimized for fast focal ratio systems. While it can function in slower systems, it is purpose-built to deliver maximum performance in high-speed optical configurations.\u003c\/p\u003e\n\u003cp\u003eFor astrophotographers using RASA, Hyperstar, and other fast imaging platforms, the Antlia 3nm H-Alpha Pro Highspeed Filter provides the precision engineering required to fully exploit the capabilities of modern ultra-fast telescopes.\u003c\/p\u003e\n\u003cdiv class=\"warning\"\u003e\n\u003cimg src=\"https:\/\/cdn.shopify.com\/s\/files\/1\/0753\/5280\/1565\/files\/warning-logo.svg?%0Av=1714663206\" alt=\"Disclaimer\" width=\"25px\"\u003e\n\u003cp\u003eThis filter is not suitable for solar observation or imaging. H-alpha filters designed for solar applications are significantly narrower and specifically engineered to handle the intense light from the sun. Attempting to use this deep sky astrophotography filter for observing or imaging the sun can result in severe damage to your equipment and pose serious risk of eye injury or blindness. Always ensure that you are using the correct type of filter for solar observation to protect both yourself and your equipment.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003c\/li\u003e\n\u003cli\u003e\n\u003ctable class=\"specifications\"\u003e\n\u003ctbody\u003e\n\u003ctr\u003e\n\u003ctd\u003e\n\u003cp\u003eBasic Substrate\u003c\/p\u003e\n\u003c\/td\u003e\n\u003ctd\u003e\n\u003cp\u003eOptical, Single \/ Non-glued substrate\u003c\/p\u003e\n\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003e\n\u003cp\u003eFilter Thickness\u003c\/p\u003e\n\u003c\/td\u003e\n\u003ctd\u003e\n\u003cp\u003e2mm+\/-0.05mm\u003c\/p\u003e\n\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003e\n\u003cp\u003eFWHM (Full width at half maximum)\u003c\/p\u003e\n\u003c\/td\u003e\n\u003ctd\u003e\n\u003cp\u003e3nm\u003c\/p\u003e\n\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003e\n\u003cp\u003eCWL (Central Wavelength)\u003c\/p\u003e\n\u003c\/td\u003e\n\u003ctd\u003e\n\u003cp\u003e657.5nm (Pre-shifted for high-speed systems)\u003c\/p\u003e\n\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003e\n\u003cp\u003ePeak Transmission\u003c\/p\u003e\n\u003c\/td\u003e\n\u003ctd\u003e\n\u003cp\u003e\u0026gt;90%\u003c\/p\u003e\n\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003e\n\u003cp\u003eBlocking\u003c\/p\u003e\n\u003c\/td\u003e\n\u003ctd\u003e\n\u003cp\u003e\u0026gt; 5 OD (0.001% out of band blocking) @ 300-1000nm\u003c\/p\u003e\n\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003e\n\u003cp\u003eSurface Quality\u003c\/p\u003e\n\u003c\/td\u003e\n\u003ctd\u003e\n\u003cp\u003eS\/D (scratch\/dig)= 60\/40 (Refer to MIL-O-13830)\u003c\/p\u003e\n\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003e\n\u003cp\u003eTransmitted Wavefront\u003c\/p\u003e\n\u003c\/td\u003e\n\u003ctd\u003e\n\u003cp\u003eLambda\/4 or better.\u003c\/p\u003e\n\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003e\n\u003cp\u003eParallelism\u003c\/p\u003e\n\u003c\/td\u003e\n\u003ctd\u003e\n\u003cp\u003eLess than 30 arcsec\u003c\/p\u003e\n\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003e\n\u003cp\u003eSubstrate\u003c\/p\u003e\n\u003c\/td\u003e\n\u003ctd\u003e\n\u003cp\u003eSingle \/ Non-glued\u003c\/p\u003e\n\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003c\/tbody\u003e\n\u003c\/table\u003e\n\u003c\/li\u003e\n\u003cli\u003e\n\u003cul\u003e\n\u003cli\u003eFilter\u003c\/li\u003e\n\u003cli\u003eFilter Case\u003c\/li\u003e\n\u003cli\u003eTransmission graph\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003c\/li\u003e\n\u003c\/ul\u003e","brand":"Antlia","offers":[{"title":"1.25\" Mounted","offer_id":50935097098525,"sku":"ANT-HA-3NM-HS-1.25","price":268.0,"currency_code":"USD","in_stock":true},{"title":"31mm Unmounted","offer_id":50935097131293,"sku":"ANT-HA-3NM-HS-RD31","price":288.0,"currency_code":"USD","in_stock":true},{"title":"36mm Unmounted","offer_id":50935097164061,"sku":"ANT-HA-3NM-HS-RD36","price":325.0,"currency_code":"USD","in_stock":true},{"title":"2\" Mounted","offer_id":50935097196829,"sku":"ANT-HA-3NM-HS-2","price":420.0,"currency_code":"USD","in_stock":true},{"title":"50mm Unmounted","offer_id":50935097229597,"sku":"ANT-HA-3NM-HS-RD50","price":515.0,"currency_code":"USD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0753\/5280\/1565\/products\/Antlia-Ha-Pro__26276.1670360748.1280.1280.jpg?v=1770824812","url":"https:\/\/davidastro.com\/fr-us\/products\/antlia-3nm-narrowband-h-alpha-pro-highspeed-filter","provider":"David Astro","version":"1.0","type":"link"}