{"id":3875,"date":"2025-03-06T20:40:31","date_gmt":"2025-03-06T19:40:31","guid":{"rendered":"https:\/\/deep-space-astronomy.geekworkers.dev\/produit\/filtre-chroma-h-alpha-5nm\/"},"modified":"2025-06-03T10:40:49","modified_gmt":"2025-06-03T08:40:49","slug":"filtre-chroma-h-alpha-5nm","status":"publish","type":"product","link":"https:\/\/deep-space-astronomy.ch\/en\/product\/filtre-chroma-h-alpha-5nm\/","title":{"rendered":"Chroma H-alpha filter 5nm - 2\u2033 Mounted"},"content":{"rendered":"<h3>Chroma 5nm H-alpha filter<\/h3>\n<p>The filter <strong>H-alpha 5nm from Chroma<\/strong> is a narrow-band filter designed for imaging nebulae and other objects rich in ionized hydrogen. With a bandwidth centered on the H-alpha line at 656.3 nm, it offers exceptional performance for astrophotography, particularly in environments subject to heavy light pollution.<\/p>\n<h4>Key features<\/h4>\n<ul>\n<li><strong>Bandwidth :<\/strong> 5 nm, enabling precise isolation of the H-alpha line while suppressing unwanted wavelengths such as those of sodium or mercury vapor lamps.<\/li>\n<li><strong>High transmission :<\/strong> Up to 90 % at 656.3 nm, guaranteeing an excellent signal-to-noise ratio.<\/li>\n<li><strong>Optical quality :<\/strong>\n<ul>\n<li>Surface polished to an accuracy of \u03bb\/4.<\/li>\n<li>Multilayer anti-reflective coating on both sides to prevent halos and stray reflections.<\/li>\n<\/ul>\n<\/li>\n<li><strong>Available formats :<\/strong>\n<ul>\n<li>1.25\" (mounted)<\/li>\n<li>2\" (mounted)<\/li>\n<li>31 mm and 36 mm (unmounted)<\/li>\n<\/ul>\n<\/li>\n<li><strong>Substrate thickness :<\/strong> Approx. 3 mm \u00b10.05 mm.<\/li>\n<li><strong>Parallelism :<\/strong> &lt; 30 arcsec, guaranteeing optimum image quality.<\/li>\n<\/ul>\n<h4>Applications<\/h4>\n<ul>\n<li><strong>Imaging emission nebulae :<\/strong>\n<ul>\n<li>Perfect for capturing HII regions rich in ionized hydrogen.<\/li>\n<li>Recommended for planetary and diffuse nebulae.<\/li>\n<\/ul>\n<\/li>\n<li><strong>Reducing light pollution :<\/strong>\n<ul>\n<li>Ideal for astrophotographers working in urban or suburban areas.<\/li>\n<\/ul>\n<\/li>\n<li><strong>Compatibility with high-speed systems :<\/strong>\n<ul>\n<li>Optimized for focal ratios up to f\/4.0. For faster systems (f\/2.6 to f\/3.6), we recommend using the \u201cHigh-Speed\u201d version to compensate for the blueshift.<\/li>\n<\/ul>\n<\/li>\n<\/ul>\n<h4>Technical advantages<\/h4>\n<ul>\n<li><strong>Exceptional durability :<\/strong>\n<ul>\n<li>Manufactured with sputter coatings on a single high-quality optical glass substrate, eliminating the need for laminations.<\/li>\n<li>The filters are resistant to extreme variations in temperature and humidity, guaranteeing long-term spectral stability.<\/li>\n<\/ul>\n<\/li>\n<li><strong>Anti-halos design :<\/strong> Anti-reflective coatings eliminate halos around bright stars and maximize light transmission.<\/li>\n<li><strong>Easy orientation :<\/strong> An arrow on the edge of the filter indicates the correct direction to minimize autofluorescence and maximize performance.<\/li>\n<\/ul>\n<h4>Conclusion<\/h4>\n<p>The filter <strong>Chroma H-alpha 5nm<\/strong> is a top-of-the-range choice for astrophotographers wishing to capture detailed, high-contrast images of the deep sky. Its optical precision, high transmission and ability to effectively reduce light pollution make it an indispensable tool for professional or advanced amateur imaging.<\/p>","protected":false},"excerpt":{"rendered":"<p>Filtre H-alpha 5nm de Chroma Le filtre H-alpha 5nm de Chroma est un filtre \u00e0 bande \u00e9troite con\u00e7u pour l\u2019imagerie des n\u00e9buleuses et autres objets riches en hydrog\u00e8ne ionis\u00e9. Avec une bande passante centr\u00e9e sur la raie H-alpha \u00e0 656,3 nm, il offre des performances exceptionnelles pour l\u2019astrophotographie, notamment dans des environnements soumis \u00e0 une [&hellip;]<\/p>\n","protected":false},"featured_media":3869,"comment_status":"open","ping_status":"closed","template":"","meta":[],"product_brand":[582],"product_cat":[780],"product_tag":[],"class_list":{"0":"post-3875","1":"product","2":"type-product","3":"status-publish","4":"has-post-thumbnail","6":"product_brand-chroma","7":"product_cat-filtres-bande-etroite","9":"first","10":"on_supplier","11":"taxable","12":"shipping-taxable","13":"purchasable","14":"product-type-simple"},"_links":{"self":[{"href":"https:\/\/deep-space-astronomy.ch\/en\/wp-json\/wp\/v2\/product\/3875","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/deep-space-astronomy.ch\/en\/wp-json\/wp\/v2\/product"}],"about":[{"href":"https:\/\/deep-space-astronomy.ch\/en\/wp-json\/wp\/v2\/types\/product"}],"replies":[{"embeddable":true,"href":"https:\/\/deep-space-astronomy.ch\/en\/wp-json\/wp\/v2\/comments?post=3875"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/deep-space-astronomy.ch\/en\/wp-json\/wp\/v2\/media\/3869"}],"wp:attachment":[{"href":"https:\/\/deep-space-astronomy.ch\/en\/wp-json\/wp\/v2\/media?parent=3875"}],"wp:term":[{"taxonomy":"product_brand","embeddable":true,"href":"https:\/\/deep-space-astronomy.ch\/en\/wp-json\/wp\/v2\/product_brand?post=3875"},{"taxonomy":"product_cat","embeddable":true,"href":"https:\/\/deep-space-astronomy.ch\/en\/wp-json\/wp\/v2\/product_cat?post=3875"},{"taxonomy":"product_tag","embeddable":true,"href":"https:\/\/deep-space-astronomy.ch\/en\/wp-json\/wp\/v2\/product_tag?post=3875"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}