{"title":"Filtres antipollution lumineuse Optolong","description":"\u003cp\u003eLes filtres antipollution lumineuse Optolong sont des filtres à large bande qui réduisent la lueur du ciel due à l'éclairage artificiel tout en gardant un équilibre de couleurs naturel sur les étoiles et les galaxies. La collection comprend le L-Pro, les CLS et CLS-CCD, le filtre Clear Sky et un kit de filtres clip L-Pro + UHC pour les appareils compatibles.\u003c\/p\u003e\u003cp\u003eContrairement aux filtres à bande étroite ou bibandes, ils conviennent aussi aux galaxies, aux amas et aux nébuleuses par réflexion.\u003c\/p\u003e","products":[{"product_id":"optolong-l-pro-filter","title":"Optolong Filtre L-Pro","description":"\u003cul class=\"DAV-feature-list\"\u003e\n\u003cli\u003eFiltre de réduction de la pollution lumineuse\u003c\/li\u003e\n\u003cli\u003eConserve la balance\u0026nbsp;naturel des couleurs de vos images\u003c\/li\u003e\n\u003cli\u003eEfficace pour une utilisation dans les zones polluées par la lumière\u003c\/li\u003e\n\u003cli\u003eConvient à un usage visuel et photographique\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\u003eCaractéristiques\u003c\/li\u003e\n\u003cli\u003eDans la boîte\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003cul class=\"tabs-content\"\u003e\n\u003cli class=\"active\"\u003e\n\u003cdiv\u003e\u003c!-- Title image text --\u003e\n\u003cdiv class=\"DAV-bg-light\"\u003e\u003c!-- Main Image --\u003e\n\u003cdiv class=\"DAV-section-center\"\u003e\n\u003ch2\u003ePrésentation du filtre Optolong L-Pro\u003c\/h2\u003e\n\u003cp\u003eLe filtre Optolong L-Pro est l'un des filtres anti-pollution lumineuse les plus polyvalents disponibles pour l'astrophotographie et l'observation visuelle. Conçu avec une technologie multi-bande passe-haut avancée, il réduit sélectivement les effets de l'éclairage artificiel, comme les lampes à vapeur de mercure et de sodium, tout en préservant les couleurs naturelles des étoiles et des objets du ciel profond. Contrairement aux filtres à bande étroite agressifs qui limitent le choix de la cible, le L-Pro atteint un équilibre délicat\u0026nbsp;: il supprime la lumière indésirable sans compromettre le réalisme des couleurs.\u003c\/p\u003e\n\u003cp\u003ePour les astrophotographes travaillant dans des zones soumises à une pollution lumineuse modérée à forte, l'Optolong L-Pro est souvent l'un des premiers filtres que nous recommandons. Il offre une amélioration notable du contraste et des détails sans les inconvénients des variations de couleurs artificielles. Que vous photographiiez des galaxies en large bande ou des nébuleuses en émission, le L-Pro offre des résultats constants et de haute qualité.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003c\/div\u003e\n\u003c!-- image text --\u003e\n\u003cdiv class=\"DAV-section-container\"\u003e\u003c!-- Text Section --\u003e\n\u003cdiv class=\"DAV-section-text\"\u003e\n\u003ch3\u003eSuppression de la pollution lumineuse\u003c\/h3\u003e\n\u003cp\u003eLe filtre L-Pro est efficace en réduisant sélectivement la transmission de longueurs d'onde spécifiques associées à la pollution lumineuse artificielle, notamment les lampes à vapeur de mercure, à vapeur de sodium haute et basse pression. De plus, il atténue la lumière naturelle indésirable causée par l'émission d'oxygène neutre, source de la luminescence nocturne. Parallèlement, le filtre L-Pro maintient une transparence élevée sur les principales raies d'émission des nébuleuses\u0026nbsp;: H-alpha (656\u0026nbsp;nm), OIII (496\u0026nbsp;nm et 500\u0026nbsp;nm), H-bêta (486\u0026nbsp;nm) et SII (672\u0026nbsp;nm). Ce profil de transmission précis améliore le contraste et les détails, ce qui en fait un filtre idéal pour les applications d'imagerie et de visualisation haut de gamme en environnements périurbains et urbains.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003c!-- Image Section --\u003e\n\u003cdiv class=\"DAV-section-img\"\u003e\u003cimg alt=\"Comparaison Optolong L-Pro\" src=\"https:\/\/cdn.shopify.com\/s\/files\/1\/0753\/5280\/1565\/files\/Optolong-L-Pro-comparison.jpg?v=1756067242\"\u003e\u003c\/div\u003e\n\u003c\/div\u003e\n\u003c!-- image text --\u003e\n\u003cdiv class=\"DAV-section-container\"\u003e\u003c!-- Text Section --\u003e\n\u003cdiv class=\"DAV-section-text\"\u003e\n\u003ch3\u003eVéritable équilibre des couleurs\u003c\/h3\u003e\n\u003cp\u003eL'un des atouts majeurs de l'Optolong L-Pro est son profil de transmission équilibré. Ce filtre présente un très faible taux de réduction de transmission pour les objets célestes à large bande passante. Cette propriété lui confère une efficacité exceptionnelle pour supprimer la pollution lumineuse sans impacter significativement les caractéristiques spectrales naturelles d'objets tels que les galaxies et les nébuleuses par réflexion. C'est une caractéristique essentielle pour l'astrophotographie, qui exige une reproduction fidèle des couleurs, garantissant ainsi aux images un aspect naturel avec un post-traitement minimal.\u003c\/p\u003e\n\u003ch3\u003eBlocage UV et IR\u003c\/h3\u003e\n\u003cp\u003eLa conception du filtre L-Pro supprime intrinsèquement les longueurs d'onde ultraviolettes (UV) et infrarouges (IR). Cette fonctionnalité simplifie le flux d'imagerie en éliminant le besoin d'un filtre anti-IR distinct, ce qui permet de l'utiliser pour l'imagerie du canal «\u0026nbsp;L\u0026nbsp;» (luminance) avec les caméras CMOS. Cette capacité de blocage complète garantit que la lumière parasite provenant des deux extrémités du spectre visible n'interfère pas avec l'image finale.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003c!-- Image Section --\u003e\n\u003cdiv class=\"DAV-section-img\"\u003e\u003cimg alt=\"Graphique de transmission Optolong L-Pro\" src=\"https:\/\/cdn.shopify.com\/s\/files\/1\/0753\/5280\/1565\/files\/Optolong-L-Pro-Transmission-Graph.png?v=1756067243\"\u003e\u003c\/div\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-section-container\"\u003e\u003c!-- Text Section --\u003e\n\u003cdiv class=\"DAV-section-text\"\u003e\n\u003ch3\u003ePour l'imagerie et l'utilisation visuelle\u003c\/h3\u003e\n\u003cp\u003eBien qu'optimisé pour l'astrophotographie, le L-Pro profite également aux observateurs visuels, offrant des arrière-plans plus sombres et un contraste amélioré lors de la visualisation sous un ciel urbain ou suburbain.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003c!-- Image Section --\u003e\n\u003cdiv class=\"DAV-section-img\"\u003e\u003cimg alt=\"Filtre L-Pro installé sur l'oculaire\" src=\"https:\/\/cdn.shopify.com\/s\/files\/1\/0753\/5280\/1565\/files\/Optolong-L-Pro-on-Eyepiece.png?v=1756067242\"\u003e\u003c\/div\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-section-container\"\u003e\u003c!-- Text Section --\u003e\n\u003cdiv class=\"DAV-section-text\"\u003e\n\u003ch3\u003eDisponible sous forme de filtres à clipser pour appareils photo reflex numériques et sans miroir\u003c\/h3\u003e\n\u003cp\u003eDisponible dans des tailles courantes (1,25\", 2\" et formats clipsables pour appareils photo reflex numériques), il s'intègre parfaitement aux télescopes, réfracteurs et objectifs d'appareil photo.\u003c\/p\u003e\n\u003ch4\u003eOptions de clipsage\u003c\/h4\u003e\n\u003cul\u003e\n\u003cli\u003eCanon EOS APS-C\u003c\/li\u003e\n\u003cli\u003eCanon EOS plein format\u003c\/li\u003e\n\u003cli\u003eCanon EOS R*\u003c\/li\u003e\n\u003cli\u003eNikon plein format\u003c\/li\u003e\n\u003cli\u003eSony plein format\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003cp\u003e*En raison des particularités des appareils photo Canon R, des bandes sombres verticales peuvent apparaître sur les deux bords lors de l'utilisation d'un filtre interférentiel. Il peut être nécessaire de recadrer l'image ou de la corriger en post-traitement.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003c!-- Image Section --\u003e\n\u003cdiv class=\"DAV-section-img\"\u003e\u003cimg alt=\"Filtre L-Pro installé sur un reflex numérique\" src=\"https:\/\/cdn.shopify.com\/s\/files\/1\/0753\/5280\/1565\/files\/Optolong-L-Pro-on-DSLR.jpg?v=1756067427\"\u003e\u003c\/div\u003e\n\u003c\/div\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\u003e\n\u003cp\u003eMatériel\u003c\/p\u003e\n\u003c\/td\u003e\n\u003ctd\u003e\n\u003cp\u003eVerre optique Schott B270\u003c\/p\u003e\n\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003e\n\u003cp\u003eÉpaisseur\u003c\/p\u003e\n\u003c\/td\u003e\n\u003ctd\u003e\n\u003cp\u003eFiltres à visser : 2,0 mm\u003c\/p\u003e\n\u003cp\u003eFiltres à clipser\u0026nbsp;: 1,0\u0026nbsp;mm\u003c\/p\u003e\n\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003e\n\u003cp\u003eHauteur de la cellule filtrante (versions 1,25\" et 2\")\u003c\/p\u003e\n\u003c\/td\u003e\n\u003ctd\u003e\n\u003cp\u003e4,8 mm sans filetage mâle, 6,8 mm avec filetage\u003c\/p\u003e\n\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003e\n\u003cp\u003eSpectre\u003c\/p\u003e\n\u003c\/td\u003e\n\u003ctd\u003e\n\u003cp\u003e380-750 nm\u003c\/p\u003e\n\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003e\n\u003cp\u003eQualité de surface\u003c\/p\u003e\n\u003c\/td\u003e\n\u003ctd\u003e\n\u003cp\u003e60\/40 (se référer à MIL-O-13830)\u003c\/p\u003e\n\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003e\n\u003cp\u003ePolissage optique\u003c\/p\u003e\n\u003c\/td\u003e\n\u003ctd\u003e\n\u003cp\u003ePoli optiquement pour garantir un front d'onde précis de 1\/4 et un parallélisme \u0026lt; 30 secondes\u003c\/p\u003e\n\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003e\n\u003cp\u003eTransmission\u003c\/p\u003e\n\u003c\/td\u003e\n\u003ctd\u003e\n\u003cp\u003eTransmission élevée aux principales raies d'émission des nébuleuses : H-alpha (656 nm), OIII (496 nm et 500 nm), SII (672 nm) et H-beta (486 nm)\u003c\/p\u003e\n\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003e\n\u003cp\u003eBlocage\u003c\/p\u003e\n\u003c\/td\u003e\n\u003ctd\u003e\n\u003cp\u003eBlocage hors bande de précision des principales raies d'émission de pollution lumineuse artificielle : Na (589 nm), Hg (435 nm et 578 nm)\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 class=\"DAV-grid\"\u003e\n\u003cli class=\"DAV-grid-item\"\u003e\u003cimg class=\"DAV-img-box\" alt=\"Filtre L-Pro\" src=\"https:\/\/cdn.shopify.com\/s\/files\/1\/0753\/5280\/1565\/files\/Optolong-L-Pro-2inch__58386.1612893783.1280.1280_dd518ef8-57b9-43a5-ac1c-d450992a2b0a.jpg?v=1698452919\"\u003e\n\u003cdiv\u003e\n\u003cp class=\"DAV-item-title\"\u003eFiltre L-Pro\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\u003cimg class=\"DAV-img-box\" alt=\"Boîtier de filtre en plastique\" src=\"https:\/\/cdn.shopify.com\/s\/files\/1\/0753\/5280\/1565\/files\/Optolong-Filter-Case.png?v=1756067596\"\u003e\n\u003cdiv\u003e\n\u003cp class=\"DAV-item-title\"\u003eBoîtier de filtre en plastique\u003c\/p\u003e\n\u003cp class=\"DAV-item-subtitle\"\u003e× 1\u003c\/p\u003e\n\u003c\/div\u003e\n\u003c\/li\u003e\n\u003c!-- Add more items as needed --\u003e\u003c\/ul\u003e\n\u003c\/li\u003e\n\u003c\/ul\u003e","brand":"Optolong","offers":[{"title":"1.25\" Monté","offer_id":44967780811037,"sku":"OPT-10201","price":199.0,"currency_code":"CAD","in_stock":true},{"title":"2\" Monté","offer_id":44967780843805,"sku":"OPT-10202","price":279.0,"currency_code":"CAD","in_stock":true},{"title":"Clip pour Canon EOS APS-C","offer_id":44967780909341,"sku":"OPT-10203","price":349.0,"currency_code":"CAD","in_stock":true},{"title":"Clip pour Canon EOS Plein Format","offer_id":44967780942109,"sku":"OPT-LPRO-EOS-FF","price":377.0,"currency_code":"CAD","in_stock":true},{"title":"Clip pour Nikon Plein Format","offer_id":44967780974877,"sku":"OPT-LPRO-NIKON-FF","price":377.0,"currency_code":"CAD","in_stock":true},{"title":"Clip pour Sony Plein Format","offer_id":44967781007645,"sku":"OPT-10208","price":377.0,"currency_code":"CAD","in_stock":true},{"title":"Clip pour Canon EOS-R","offer_id":44967781040413,"sku":"OPT-10211","price":349.0,"currency_code":"CAD","in_stock":true},{"title":"Clip for Nikon Z Full Frame","offer_id":52942348484893,"sku":"OPT-LPRO-NK-Z","price":349.0,"currency_code":"CAD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0753\/5280\/1565\/products\/Optolong-L-Pro-2inch__58386.1612893783.1280.1280.jpg?v=1684345839"},{"product_id":"optolong-clear-sky-filter","title":"Optolong Clear Sky Light Pollution Filter","description":"\u003cul class=\"DAV-feature-list\"\u003e\n\u003cli\u003eSuppresses common sources of urban light pollution\u003c\/li\u003e\n\u003cli\u003eEnhances contrast for deep-sky objects\u003c\/li\u003e\n\u003cli\u003eImproves natural color balance in astrophotography\u003c\/li\u003e\n\u003cli\u003eDurable, scratch-resistant Ion-assisted coatings\u003c\/li\u003e\n\u003cli\u003eAvailable in M77\/M82 lens thread and Nikon Z clip-in formats\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\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 Clear Sky Light Pollution Filter\u003c\/h2\u003e\n      \u003cp\u003eThe Optolong Clear Sky Light Pollution Filter is engineered to reclaim the natural contrast and color of the night sky from light-polluted locations. By selectively blocking the most common wavelengths of artificial lighting, this filter allows the faint light from nebulae and galaxies to stand out against a darker background. It utilizes advanced ion-assisted deposition coatings to ensure durability and stable performance, making it an essential tool for DSLR and mirrorless camera astrophotography in urban and suburban environments.\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\u003eRestoring Natural Sky Contrast from the City\u003c\/h3\u003e\n      \u003cp\u003eShooting from a city or suburb washes out faint deep-sky objects, blending them into a bright, hazy background. The Optolong Clear Sky filter targets and suppresses the spectral lines of common streetlights and artificial skyglow, effectively darkening the sky without altering the natural color of stars and galaxies. This process dramatically enhances the contrast between your target and the background, revealing detail that would otherwise be lost.\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 Durability and Color Fidelity\u003c\/h3\u003e\n      \u003cp\u003eOptolong employs a sophisticated ion-assisted deposition coating process to create a filter that is both effective and resilient. This technology produces a hard, scratch-resistant surface and ensures the central wavelength of the filter remains stable regardless of temperature changes during an imaging session. The precision and homogeneity of these coatings result in high transmission of desirable wavelengths, preserving true-to-life color balance for a more natural final image.\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\"\u003eHow does the Optolong Clear Sky Filter improve astrophotography from a city?\u003c\/h3\u003e\n  \u003c\/div\u003e\n  \u003cdiv class=\"DAV-accordion-A\"\u003e\n    \u003cp\u003eThe Optolong Clear Sky Filter works by selectively blocking the most common wavelengths of light emitted by artificial sources like sodium and mercury-vapor streetlights. This darkens the sky background in your images, which significantly \u003cstrong\u003eincreases the contrast\u003c\/strong\u003e of celestial objects like galaxies and nebulae, making them stand out more clearly.\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 Optolong Clear Sky filter and a stronger nebula filter like a UHC?\u003c\/h3\u003e\n  \u003c\/div\u003e\n  \u003cdiv class=\"DAV-accordion-A\"\u003e\n    \u003cp\u003eThe Clear Sky filter is a \u003cstrong\u003ebroadband light pollution filter\u003c\/strong\u003e, designed to improve contrast while maintaining natural star color, making it great for galaxies and star clusters. A UHC (Ultra High Contrast) filter is a \u003cstrong\u003enarrowband filter\u003c\/strong\u003e that passes only specific emission lines (like H-Beta and OIII), resulting in a much darker sky but also a significant color cast. UHC filters are specialized for emission nebulae, while the Clear Sky filter is more versatile.\u003c\/p\u003e\n  \u003c\/div\u003e\n  \u003cdiv class=\"DAV-accordion\"\u003e\n    \u003ch3 class=\"DAV-accordion-Q\"\u003eWill the Optolong Clear Sky Filter change the color of stars in my images?\u003c\/h3\u003e\n  \u003c\/div\u003e\n  \u003cdiv class=\"DAV-accordion-A\"\u003e\n    \u003cp\u003eThe filter is designed to produce a natural color balance with minimal color cast. While any filter that removes parts of the spectrum will have some effect, the Optolong Clear Sky filter aims to preserve the natural coloration of stars and broadband targets like galaxies, making color correction in post-processing much simpler than with more aggressive narrowband filters.\u003c\/p\u003e\n  \u003c\/div\u003e\n  \u003cdiv class=\"DAV-accordion\"\u003e\n    \u003ch3 class=\"DAV-accordion-Q\"\u003eHow do I choose between the lens thread and clip-in versions of the Optolong Clear Sky Filter?\u003c\/h3\u003e\n  \u003c\/div\u003e\n  \u003cdiv class=\"DAV-accordion-A\"\u003e\n    \u003cp\u003eChoose the version based on your equipment and needs:\u003c\/p\u003e\n    \u003cul\u003e\n      \u003cli\u003e\n\u003cstrong\u003eLens Thread (M77, M82):\u003c\/strong\u003e This type screws directly onto the front of your camera lens, just like a standard UV filter. It's ideal if you primarily use one or two lenses with the same filter thread size.\u003c\/li\u003e\n      \u003cli\u003e\n\u003cstrong\u003eClip-in Filter:\u003c\/strong\u003e This version fits inside the camera body, just behind the lens mount. This allows you to use the filter with \u003cstrong\u003eany lens\u003c\/strong\u003e compatible with your camera body (e.g., Nikon Z mount), which is more economical if you frequently switch between different lenses.\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 Optolong Clear Sky Filter to photograph the Andromeda Galaxy (M31) from a suburban backyard?\u003c\/h3\u003e\n  \u003c\/div\u003e\n  \u003cdiv class=\"DAV-accordion-A\"\u003e\n    \u003cp\u003eYes, absolutely. The Andromeda Galaxy (M31) is a perfect target for this filter. As a broadband object (a galaxy made of stars), it benefits greatly from the increased contrast the Clear Sky filter provides against a light-polluted suburban sky, helping to reveal its faint outer arms and dust lanes without distorting its natural color.\u003c\/p\u003e\n  \u003c\/div\u003e\n  \u003cdiv class=\"DAV-accordion\"\u003e\n    \u003ch3 class=\"DAV-accordion-Q\"\u003eIs the Optolong Clear Sky Filter effective for shooting the Orion Nebula (M42) with a standard DSLR?\u003c\/h3\u003e\n  \u003c\/div\u003e\n  \u003cdiv class=\"DAV-accordion-A\"\u003e\n    \u003cp\u003eYes, the Optolong Clear Sky Filter is very effective for bright emission nebulae like the Orion Nebula (M42). It will help suppress local light pollution, making the faint, extended nebulosity more visible against a dark background while preserving the natural colors in the bright core and surrounding star field.\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 Mounting Options\u003c\/td\u003e\n\u003ctd\u003eM77 Lens Thread, M82 Lens Thread, Clip-in for Nikon Z Full Frame\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":"M77 Lens Thread","offer_id":52941912113437,"sku":"OPT-10503","price":231.0,"currency_code":"CAD","in_stock":true},{"title":"M82 Lens Thread","offer_id":52941912146205,"sku":"OPT-10504","price":287.0,"currency_code":"CAD","in_stock":true},{"title":"Clip for Nikon Z Full Frame","offer_id":52941912178973,"sku":"OPT-CLEARSKY-NK-Z","price":139.0,"currency_code":"CAD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0753\/5280\/1565\/files\/Optolong-Clear-Sky-Filter-Screw-on-Lens-1_70b48089-a026-41d6-a39c-0cb0db0499d1.jpg?v=1789592341"},{"product_id":"optolong-cls-filter","title":"Optolong CLS Light Pollution Filter","description":"\u003cul class=\"DAV-feature-list\"\u003e\n\u003cli\u003eSuppresses common light pollution sources\u003c\/li\u003e\n\u003cli\u003eAverage transmission greater than 90% on key nebula emission lines\u003c\/li\u003e\n\u003cli\u003eBlocks light pollution lines with \u0026gt;99% efficiency\u003c\/li\u003e\n\u003cli\u003e1.85mm thick optical glass substrate\u003c\/li\u003e\n\u003cli\u003eλ\/4 transmitted wavefront and 30s parallelism\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\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 CLS Light Pollution Filter\u003c\/h2\u003e\n\u003cp\u003eThe Optolong CLS (City Light Suppression) filter restores contrast to your deep-sky views by blocking over 99% of common artificial light sources. Built on a 1.85mm optical glass substrate, it maintains a λ\/4 transmitted wavefront for sharp images while delivering over 90% transmission of critical nebula emission lines like H-alpha and OIII. With 30s parallelism, the filter introduces no optical distortions, making it a powerful tool for visual observers and imagers using color cameras or unmodified DSLRs under suburban skies.\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\u003eTargeted Light Pollution Suppression: \u0026gt;99% Blocking of Sodium \u0026amp; Mercury Lines\u003c\/h3\u003e\n\u003cp\u003eThe core function of the Optolong CLS is to surgically remove the wavelengths associated with common streetlights. It achieves greater than 99% blocking of mercury vapor, high-pressure sodium, and low-pressure sodium vapor lamp emissions. This aggressive rejection of unwanted light darkens the sky background significantly, allowing the faint signal from your target to stand out in much higher contrast.\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-Transmission Broadband Design: \u0026gt;90% Pass-Through on Key Emission Lines\u003c\/h3\u003e\n\u003cp\u003eWhile blocking unwanted light, the CLS filter maintains an average transmission of over 90% for the most important deep-sky wavelengths. This wide passband includes hydrogen-alpha (656nm), hydrogen-beta (486nm), oxygen-III (496nm and 500nm), and sulfur-II (672nm). By preserving the light from these emission nebulae, the filter reveals more detail and structure in objects like the Orion Nebula (M42) or the Lagoon Nebula (M8) without significantly altering natural star colors.\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-Coated 1.85mm Glass: λ\/4 Wavefront and 30s Parallelism\u003c\/h3\u003e\n\u003cp\u003eOptolong constructs the CLS filter from a 1.85mm thick slab of fine optical glass, ensuring mechanical stability and optical purity. Ion-assisted deposition coatings provide durability and prevent the central wavelength from shifting with temperature changes. The filter is polished to a transmitted wavefront of λ\/4 and a parallelism of 30 arcseconds, guaranteeing that it will not degrade the resolution of your telescope's optics.\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 CLS vs. UHC Filters: Choosing the Right Tool for Your Sky\u003c\/h3\u003e\n\u003cp\u003eThe CLS is often compared to Ultra High Contrast (UHC) filters. The primary difference is the width of the passband.\u003c\/p\u003e\n\u003cul\u003e\n\u003cli\u003e\n\u003cstrong\u003eOptolong CLS Filter:\u003c\/strong\u003e Features a wider passband, making it more effective in mild to moderate light pollution. It preserves more natural star color and is a better general-purpose filter for a mix of objects, including reflection nebulae and star clusters.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eUHC Filter:\u003c\/strong\u003e Has a narrower passband, primarily focused on the H-beta and OIII lines. This provides more aggressive contrast on emission nebulae but can dim stars more significantly. It is often preferred for darker sites or areas with more severe light pollution where maximum rejection is needed.\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 main difference between the Optolong CLS and a UHC filter?\u003c\/h3\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion-A\"\u003e\n\u003cp\u003eThe \u003cstrong\u003eOptolong CLS filter\u003c\/strong\u003e has a wider bandpass, making it a \"broadband\" filter ideal for mild to moderate light pollution. It passes more of the visible spectrum, resulting in more natural star colors. A UHC filter is a \"narrowband\" filter with a tighter passband, offering higher contrast on emission nebulae but at the cost of dimming stars more, making it better suited for more heavily 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 Optolong CLS filter for imaging galaxies like Andromeda (M31)?\u003c\/h3\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion-A\"\u003e\n\u003cp\u003eYes, but with limitations. Galaxies are broadband targets, meaning they emit light across the entire visible spectrum. The \u003cstrong\u003eOptolong CLS filter\u003c\/strong\u003e will increase the contrast between the galaxy and the skyglow, but it will also block some of the galaxy's own light. It can help bring out H-II regions in the spiral arms but may reduce the overall brightness of the galactic core.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion\"\u003e\n\u003ch3 class=\"DAV-accordion-Q\"\u003eHow will the Optolong CLS filter perform on 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\u003eThe \u003cstrong\u003eOptolong CLS filter\u003c\/strong\u003e is an excellent choice for this scenario. M42 is rich in hydrogen-alpha and oxygen-III emissions, which the filter transmits with over 90% efficiency. In your 8\" SCT, the filter will dramatically darken the suburban sky background, making the faint outer loops of the nebula visible and enhancing the contrast and detail within the Trapezium region.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion\"\u003e\n\u003ch3 class=\"DAV-accordion-Q\"\u003eIs the Optolong CLS filter suitable for an unmodified DSLR camera?\u003c\/h3\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion-A\"\u003e\n\u003cp\u003eYes, the \u003cstrong\u003eOptolong CLS filter\u003c\/strong\u003e is designed to work very well with color CMOS\/CCD cameras and unmodified DSLRs. Its passband includes the critical 656nm H-alpha line, which standard DSLRs are less sensitive to but still capture. The filter helps isolate this important wavelength from light pollution, improving the signal in your images.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion\"\u003e\n\u003ch3 class=\"DAV-accordion-Q\"\u003eDoes the Optolong CLS filter make nebulae look brighter?\u003c\/h3\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion-A\"\u003e\n\u003cp\u003eNo, this is a common misconception. No filter can increase an object's actual brightness. The \u003cstrong\u003eOptolong CLS filter\u003c\/strong\u003e works by increasing the *contrast* between the nebula and the night sky. It achieves this by selectively blocking light pollution, which makes the background darker, thereby making the nebula easier to see against it.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion\"\u003e\n\u003ch3 class=\"DAV-accordion-Q\"\u003eWhy does my Optolong CLS filter look like a mirror and change colors?\u003c\/h3\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion-A\"\u003e\n\u003cp\u003eThis is normal for an interference filter like the \u003cstrong\u003eOptolong CLS\u003c\/strong\u003e. The highly reflective appearance is due to the dielectric coatings that are precisely layered to reject specific wavelengths of light. The color will appear to shift depending on the viewing angle and ambient light, which is a sign that the coatings are functioning as designed.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion\"\u003e\n\u003ch3 class=\"DAV-accordion-Q\"\u003eWARNING: Can I use the Optolong CLS filter for observing the Sun?\u003c\/h3\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion-A\"\u003e\n\u003cp\u003e\u003cstrong\u003eAbsolutely not.\u003c\/strong\u003e The Optolong CLS filter is NOT a solar filter and is not designed for sun observation. Looking at the Sun with this filter, or any filter not explicitly designed for safe solar viewing, will cause immediate and permanent blindness.\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\u003eBroadband Light Pollution Suppression (CLS)\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eAvailable Sizes\u003c\/td\u003e\n\u003ctd\u003e1.25\" Mounted, 2\" Mounted\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eSubstrate\u003c\/td\u003e\n\u003ctd\u003eOptical glass\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eThickness\u003c\/td\u003e\n\u003ctd\u003e1.85mm\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eAverage Transmission\u003c\/td\u003e\n\u003ctd\u003e\u0026gt;90%\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eBlocking Range\u003c\/td\u003e\n\u003ctd\u003e400-700nm\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eBlocking Depth\u003c\/td\u003e\n\u003ctd\u003e\u0026gt;99% on light pollution lines\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eTransmitted Wavefront\u003c\/td\u003e\n\u003ctd\u003eλ\/4\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eParallelism\u003c\/td\u003e\n\u003ctd\u003e30s\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eSurface Quality\u003c\/td\u003e\n\u003ctd\u003e60\/40\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\"\u003eOptolong CLS Light Pollution 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\"\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\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":52941921288477,"sku":"OPT-11801","price":77.0,"currency_code":"CAD","in_stock":true},{"title":"2\" Mounted","offer_id":52941921321245,"sku":"OPT-11802","price":119.0,"currency_code":"CAD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0753\/5280\/1565\/files\/Optolong-CLS-City-Light-Suppression-broadband-filter-is-designed-to-improve-the-visibility-of-various-deepsky-objects-1_1622ccd9-042b-4aec-b31c-a974b2ff5095.jpg?v=1789592400"},{"product_id":"optolong-cls-ccd-filter","title":"Optolong CLS-CCD Light Pollution Filter","description":"\u003cul class=\"DAV-feature-list\"\u003e\n\u003cli\u003eBlocks \u0026gt;99% of primary light pollution emission lines\u003c\/li\u003e\n\u003cli\u003eAchieves \u0026gt;90% average transmission on key nebula wavelengths\u003c\/li\u003e\n\u003cli\u003eIntegrated 300-1100nm UV\/IR cut filter for color cameras\u003c\/li\u003e\n\u003cli\u003eλ\/4 transmitted wavefront and 30s parallelism for sharp stars\u003c\/li\u003e\n\u003cli\u003e1.85mm thick optical glass 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\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 CLS-CCD Light Pollution Filter\u003c\/h2\u003e\n\u003cp\u003eThe Optolong CLS-CCD Light Pollution Filter is engineered to reclaim contrast in your astrophotos by blocking over 99% of common light pollution sources while maintaining an average transmission greater than 90% on critical nebula emission lines. Its integrated 300-1100nm blocking range makes it a single-filter solution for color CCD and modified DSLR cameras, eliminating star bloat from infrared without needing a separate IR-cut filter. The 1.85mm optical glass substrate is polished to a λ\/4 transmitted wavefront, ensuring your system's resolution is not compromised.\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 \u0026gt;99% of Sodium and Mercury Vapor Lines\u003c\/h3\u003e\n\u003cp\u003eThis filter's primary function is to surgically remove the wavelengths associated with urban skyglow. It achieves a blocking depth of over 99% for mercury vapor, high-pressure sodium, and low-pressure sodium vapor lamps—the most common sources of artificial light pollution. By rejecting this unwanted light, the background sky in your images becomes significantly darker, allowing the faint, complex structures of nebulae to 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\u003eOver 90% Transmission on H-alpha, OIII, and SII\u003c\/h3\u003e\n\u003cp\u003eWhile aggressively blocking pollutants, the CLS-CCD maintains an average transmission rate (Tave) of over 90% across the most important emission lines for deep-sky objects. This high throughput applies to hydrogen-alpha (656nm), oxygen-III (496nm and 500nm), hydrogen-beta (486nm), and sulfur-II (672nm). The result is vibrant, high-contrast images of emission nebulae, planetary nebulae, and supernova remnants, with their natural colors preserved.\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 CCD Advantage: Integrated 300-1100nm IR\/UV Cut for Color Sensors\u003c\/h3\u003e\n\u003cp\u003eThe \"CCD\" in the name signifies a critical feature: a built-in UV and IR cut filter covering a wide 300-1100nm range. Many color astronomy cameras and modified DSLRs have sensors that are sensitive to infrared light, which can cause bloated, unfocused stars if not filtered out. The CLS-CCD eliminates the need for a separate L-filter (luminance\/IR-cut), simplifying your imaging train and ensuring sharp, tight stars across the frame.\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\u003eCLS-CCD vs. Standard CLS: Why IR Cut Matters\u003c\/h3\u003e\n\u003cp\u003eThe key difference between the Optolong CLS-CCD and the standard visual CLS filter is the infrared blocking. While both filters suppress the same light pollution lines, the standard CLS allows infrared light to pass through. This makes it suitable for visual use or for monochrome cameras shooting with a separate filter wheel.\u003c\/p\u003e\n\u003cul\u003e\n\u003cli\u003e\n\u003cstrong\u003eChoose the CLS-CCD if:\u003c\/strong\u003e You use a one-shot-color (OSC) camera, a color CCD, or a modified DSLR. The integrated IR-cut is essential for preventing star bloat and achieving correct color balance without an extra filter.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eChoose the standard CLS if:\u003c\/strong\u003e You are a visual observer or use a monochrome camera with a separate IR-cut filter in your luminance (L) channel.\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 main difference between the Optolong CLS-CCD and the standard CLS filter?\u003c\/h3\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion-A\"\u003e\n\u003cp\u003eThe \u003cstrong\u003eOptolong CLS-CCD\u003c\/strong\u003e includes an integrated IR\/UV cut filter that blocks wavelengths from 300-1100nm. This is essential for color cameras (OSC\/DSLR) to prevent star bloat from infrared light. The standard CLS filter does not block IR and is intended more for visual use or monochrome imaging setups that use a separate luminance filter.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion\"\u003e\n\u003ch3 class=\"DAV-accordion-Q\"\u003eCan I use the Optolong CLS-CCD filter for visual observing?\u003c\/h3\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion-A\"\u003e\n\u003cp\u003eWhile you can, it's not ideal. The filter's transmission characteristics are optimized for the response of a digital sensor. For visual use, the standard Optolong CLS filter typically provides a brighter, more natural-looking view through the eyepiece.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion\"\u003e\n\u003ch3 class=\"DAV-accordion-Q\"\u003eWill the Optolong CLS-CCD filter work with my unmodified DSLR camera?\u003c\/h3\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion-A\"\u003e\n\u003cp\u003eYes, but with limited effectiveness for certain objects. An unmodified DSLR has its own internal filter that blocks most of the deep red H-alpha light (656nm). The CLS-CCD will still improve contrast by blocking skyglow, but to capture the rich red nebulosity in objects like the North America Nebula (NGC 7000), a \"modified\" DSLR with the stock filter removed is required.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion\"\u003e\n\u003ch3 class=\"DAV-accordion-Q\"\u003eHow will the CLS-CCD filter affect imaging the Orion Nebula (M42) from a city?\u003c\/h3\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion-A\"\u003e\n\u003cp\u003eFor an object like the Orion Nebula (M42), the CLS-CCD filter will dramatically improve your results from a light-polluted area. It will darken the sky background, significantly increasing the contrast of the glowing hydrogen and oxygen gases that make up the nebula. This allows you to capture much more of the faint, extended nebulosity without the image being 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 the Optolong CLS-CCD a good choice for imaging galaxies like Andromeda (M31)?\u003c\/h3\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion-A\"\u003e\n\u003cp\u003eIt's a trade-off. Galaxies like the Andromeda Galaxy (M31) are broadband objects, meaning they emit light across the entire visible spectrum, similar to stars. A light pollution filter like the CLS-CCD will block some of the galaxy's own light along with the skyglow. While it can help darken the background, it may also alter the galaxy's natural color balance. For galaxies, less aggressive filters or simply capturing more data from a dark site is often the preferred approach.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion\"\u003e\n\u003ch3 class=\"DAV-accordion-Q\"\u003eCan I use the Optolong CLS-CCD filter to look at the Sun?\u003c\/h3\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion-A\"\u003e\n\u003cp\u003e\u003cstrong\u003eAbsolutely not.\u003c\/strong\u003e The Optolong CLS-CCD filter is \u003cstrong\u003eNOT\u003c\/strong\u003e a solar filter and is not designed for sun observation. Looking at the Sun with this filter, or any filter not explicitly designed for safe solar viewing, will cause immediate and permanent eye damage, including blindness. Always use a certified safe solar filter that covers the entire front aperture 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\u003eFilter Type\u003c\/td\u003e\n\u003ctd\u003eBroadband Light Pollution (LP) Filter with IR\/UV Cut\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eAvailable Sizes\u003c\/td\u003e\n\u003ctd\u003e1.25\" Mounted, 2\" Mounted\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eSubstrate Material\u003c\/td\u003e\n\u003ctd\u003eOptical glass\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eSubstrate Thickness\u003c\/td\u003e\n\u003ctd\u003e1.85mm\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eAverage Transmission\u003c\/td\u003e\n\u003ctd\u003e\u0026gt;90%\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eBlocking Range\u003c\/td\u003e\n\u003ctd\u003e300-1100nm\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eLight Pollution Blocking\u003c\/td\u003e\n\u003ctd\u003e\u0026gt;99%\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eSurface Quality\u003c\/td\u003e\n\u003ctd\u003e60\/40\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eTransmitted Wavefront RMS\u003c\/td\u003e\n\u003ctd\u003eλ\/4\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eParallelism\u003c\/td\u003e\n\u003ctd\u003e30s\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":52941923090717,"sku":"OPT-11901","price":133.0,"currency_code":"CAD","in_stock":true},{"title":"2\" Mounted","offer_id":52941923123485,"sku":"OPT-11902","price":223.0,"currency_code":"CAD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0753\/5280\/1565\/files\/Optolong-The-CLS-CCD-broadband-filter-is-designed-to-improve-the-visibility-of-various-deepsky-objects-1_19932723-0c05-473f-91d2-3b4f840aeed2.jpg?v=1789592410"},{"product_id":"optolong-l-pro-uhc-clip-filter-kit","title":"Optolong L-Pro + UHC Clip Filter Kit","description":"\u003cul class=\"DAV-feature-list\"\u003e\n\u003cli\u003eTwo Optolong Clip-in Light Pollution Filters in One Kit\u003c\/li\u003e\n\u003cli\u003eL-Pro: Multi-Bandpass Suppression Across 380-750nm\u003c\/li\u003e\n\u003cli\u003eUHC: \u0026gt;99% Blocking of Mercury and Sodium Vapor Light (OD3)\u003c\/li\u003e\n\u003cli\u003eNatural Color on Galaxies, High Contrast on Emission Nebulae\u003c\/li\u003e\n\u003cli\u003eFits Inside the Camera Body, Works With Any Lens\u003c\/li\u003e\n\u003cli\u003eCanon EOS APS-C, Canon EOS Full Frame and Nikon Full Frame 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 L-Pro + UHC Clip Filter Kit\u003c\/h2\u003e\n\u003cp\u003eThe Optolong L-Pro + UHC Clip Filter Kit pairs Optolong's two broadband light pollution filters in clip-in format for your DSLR. The L-Pro is the multi-bandpass filter for natural color across a 380-750nm spectrum; the UHC is the narrower, higher-contrast filter that blocks more than 99% of mercury and sodium vapor light. Both clip inside the camera body, so either one works with any lens you mount, and you choose the filter for the target and the sky rather than compromising on one.\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\u003eL-Pro: Multi-Bandpass Suppression for Natural-Color Imaging\u003c\/h3\u003e\n\u003cp\u003eThe L-Pro selectively rejects the dominant emission lines of mercury vapor, high-pressure sodium and low-pressure sodium streetlights, plus the natural skyglow from neutral oxygen in the atmosphere, across its 380-750nm operating range. Its balanced, multi-bandpass design keeps the natural colors of broadband targets such as galaxies, reflection nebulae and globular clusters, so images need far less color correction. It still passes the key nebula lines, including H-Alpha, OIII, SII and H-Beta, and it blocks infrared on its own.\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: Ultra High Contrast for Emission Nebulae Under City Skies\u003c\/h3\u003e\n\u003cp\u003eThe UHC takes the more aggressive approach. At an optical density of OD3 it blocks more than 99% of light from mercury vapor and sodium vapor lamps, while transmitting the emission lines of nebulae at OIII (496nm, 500nm), H-Beta (486nm) and H-Alpha (656nm). Its narrower passband gives higher contrast than a CLS filter, which makes it the better choice where light pollution is severe. Its substantial red passband captures H-Alpha well on unmodified DSLRs, for targets like the Orion Nebula (M42).\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\u003eChoosing Between the L-Pro and the UHC on a Given Night\u003c\/h3\u003e\n\u003cp\u003eThe two filters cover different targets, which is why they are worth having together:\u003c\/p\u003e\n\u003cul\u003e\n\u003cli\u003e\n\u003cstrong\u003eUse the L-Pro\u003c\/strong\u003e for galaxies, reflection nebulae, star clusters and Milky Way landscapes, or whenever natural star color matters. It is the more versatile filter from suburban skies.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eUse the UHC\u003c\/strong\u003e for emission nebulae from heavily light-polluted urban skies, where maximum contrast is the goal. It dims broadband targets such as galaxies, so switch back to the L-Pro for those.\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\u003eClip-in Format: Filtration Inside the Camera, Any Lens in Front\u003c\/h3\u003e\n\u003cp\u003eEach clip filter sits inside the camera body, so the light pollution filter works with whatever lens or telescope adapter you attach. The kit comes in three versions, each fitting one camera family:\u003c\/p\u003e\n\u003cul\u003e\n\u003cli\u003e\n\u003cstrong\u003eCanon EOS APS-C:\u003c\/strong\u003e including the EOS 7D, 10D, 20D, 30D, 40D, 50D, 60D\/60Da, 70D, 550D, 600D, 650D, 700D, 1100D and 1200D.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eCanon EOS Full Frame:\u003c\/strong\u003e Canon EOS full-frame DSLR bodies.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eNikon Full Frame:\u003c\/strong\u003e D600, D610, D700, D750, D800, D800E, D810, D810A and Df.\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\u003eOptical Quality and Durable Coatings\u003c\/h3\u003e\n\u003cp\u003eBoth filters are polished to a 60\/40 surface quality per MIL-O-13830, and the UHC to a transmitted wavefront of ¼ λ with 30s parallelism, so neither softens your images. Ion-assisted deposition coatings resist scratching and keep the central wavelength stable as the temperature changes through the night. Light pollution filters increase the contrast between the target and the sky; they do not make the object itself brighter.\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 difference between the L-Pro and the UHC in this kit?\u003c\/h3\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion-A\"\u003e\n\u003cp\u003eThe \u003cstrong\u003eL-Pro\u003c\/strong\u003e is a multi-bandpass filter that blocks the main streetlight wavelengths while preserving natural color, which suits galaxies, reflection nebulae and star clusters. The \u003cstrong\u003eUHC\u003c\/strong\u003e has a narrower passband and blocks more than 99% of mercury and sodium vapor light, giving higher contrast on emission nebulae from heavily light-polluted skies.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion\"\u003e\n\u003ch3 class=\"DAV-accordion-Q\"\u003eWhich version of the Optolong clip filter kit fits my camera?\u003c\/h3\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion-A\"\u003e\n\u003cp\u003eChoose the version for your camera family: \u003cstrong\u003eCanon EOS APS-C\u003c\/strong\u003e (for example the EOS 7D, 60D\/60Da, 70D, 600D, 700D), \u003cstrong\u003eCanon EOS Full Frame\u003c\/strong\u003e, or \u003cstrong\u003eNikon Full Frame\u003c\/strong\u003e (D600, D610, D700, D750, D800, D800E, D810, D810A, Df). Both filters in a kit are the same clip format.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion\"\u003e\n\u003ch3 class=\"DAV-accordion-Q\"\u003eCan I use these clip filters with an unmodified DSLR?\u003c\/h3\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion-A\"\u003e\n\u003cp\u003eYes. The UHC is suited to color cameras and \u003cstrong\u003eunmodified DSLRs\u003c\/strong\u003e, and its substantial red passband captures H-Alpha well. The L-Pro works for both visual observation and astrophotography and preserves natural color with any color camera.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion\"\u003e\n\u003ch3 class=\"DAV-accordion-Q\"\u003eWhich filter should I use to photograph the Andromeda Galaxy (M31) from the suburbs?\u003c\/h3\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion-A\"\u003e\n\u003cp\u003eUse the \u003cstrong\u003eL-Pro\u003c\/strong\u003e. It darkens the suburban sky while preserving the galaxy's natural colors. The UHC blocks much of the broadband light a galaxy emits, so it would dim M31 rather than improve it.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion\"\u003e\n\u003ch3 class=\"DAV-accordion-Q\"\u003eWhich filter should I use for the Orion Nebula (M42) from a city?\u003c\/h3\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion-A\"\u003e\n\u003cp\u003eUse the \u003cstrong\u003eUHC\u003c\/strong\u003e. It blocks the city skyglow while passing the nebula's H-Alpha, H-Beta and OIII light, bringing out faint outer structure. The L-Pro also works on M42 and keeps more natural star colors in the surrounding field, with less contrast from severely 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 these filters to look at the Sun?\u003c\/h3\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion-A\"\u003e\n\u003cp\u003e\u003cstrong\u003eNo. Never use these filters for solar observation.\u003c\/strong\u003e They are not designed for the Sun and do not block its intense radiation. Looking at the Sun through them will cause permanent blindness.\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\u003eKit Contents\u003c\/td\u003e\n\u003ctd\u003eOptolong L-Pro clip filter, Optolong UHC clip filter\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eL-Pro Spectrum\u003c\/td\u003e\n\u003ctd\u003e380-750nm\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eL-Pro Filter Type\u003c\/td\u003e\n\u003ctd\u003eMulti-bandpass light pollution filter\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eUHC Blocking Range\u003c\/td\u003e\n\u003ctd\u003e300-700nm\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eUHC Blocking Depth\u003c\/td\u003e\n\u003ctd\u003eOD3, light pollution line blocking \u0026gt;99%\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eUHC Transmitted Wavefront RMS\u003c\/td\u003e\n\u003ctd\u003e¼ λ\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eUHC Parallelism\u003c\/td\u003e\n\u003ctd\u003e30s\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eSurface Quality\u003c\/td\u003e\n\u003ctd\u003e60\/40 (MIL-O-13830)\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eCoating Technology\u003c\/td\u003e\n\u003ctd\u003eIon-assisted deposition multi-layer coatings\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eAvailable Versions\u003c\/td\u003e\n\u003ctd\u003eClip for Canon EOS APS-C, Clip for Canon EOS Full Frame, Clip for Nikon Full Frame\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\"\u003eOptolong L-Pro Clip Filter (in selected version)\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\"\u003eOptolong UHC Clip Filter (in selected version)\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":"Clip for Canon EOS APS-C","offer_id":52941931872541,"sku":"OPT-LPRO-UHC-EOS-APSC","price":419.0,"currency_code":"CAD","in_stock":true},{"title":"Clip for Canon EOS Full Frame","offer_id":52941931905309,"sku":"OPT-LPRO-UHC-EOS-FF","price":419.0,"currency_code":"CAD","in_stock":true},{"title":"Clip for Nikon Full Frame","offer_id":52941931938077,"sku":"OPT-LPRO-UHC-NIKON-FF","price":419.0,"currency_code":"CAD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0753\/5280\/1565\/files\/Optolong-UHC-L-Pro-Kit.webp?v=1789606223"}],"url":"https:\/\/davidastro.com\/fr\/collections\/optolong-light-pollution-filters.oembed","provider":"David Astro","version":"1.0","type":"link"}