{"product_id":"baader-2-red-610nm-long-pass-filter-round-mounted-fcfr-2","title":"Baader 2\" Red 610nm Long-Pass Filter - Round Mounted - FCFR-2","description":"\u003cp\u003e \u003c\/p\u003e\n\u003ccenter\u003e\n\u003ch2\u003eAbout the 2\" Baader Red 610nm Long-Pass Filter\u003c\/h2\u003e\n\u003c\/center\u003e\n\u003cp\u003eBaader Planetarium astronomy filters by far supersede the mediocre quality of common \"flame polished\" color filters. A fine optical polish and 2 mm thick glass allows the \u003cb\u003eBaader Red Filter\u003c\/b\u003e to be inserted anywhere into the optical path without introducing astigmatism or other defects. For instance, they can be used in front of a binocular viewer without degrading the image in any way. Substrates are free of striae and plane-parallel polished to within 30 seconds of arc. This eliminates any double images or ghosting due to wedge errors in the glass.\u003c\/p\u003e\n\u003cp\u003eThe filter cell features the largest clear aperture of any telescope filter on the market for complete freedom from vignetting at any focal length. The front \"crown\" incorporates milled notches, which makes handling and threading the \u003cb\u003eBaader Red Filter\u003c\/b\u003e an easy operation in the dark. All surfaces are treated with a 7-layer Multi-Coating, featuring a mere 0.25% residual reflection. It is the most elaborate coating ever applied onto amateur color filters, resulting in a filter free of any false reflections under any incident angle of light. Light is the hottest commodity for all planetary observation. Especially during high magnification work, whether you have enough light or not is the deciding factor for the recognition of the subtlest planetary surface detail, much more important than a horde of different filters of mediocre execution.\u003c\/p\u003e\n\u003cp\u003eLess is more: 7-layer MC-coatings on the \u003cb\u003eBaader Red Filter\u003c\/b\u003e not only provide a brighter image, they prevent the softening effect of scattered light! Scattered light kills exactly those subtle features in planetary detail that you are longing to see. Painstaking attention to coatings and perfect optical figuring are simple reasons why the image contrast through these premium filters is so rock-solid.\u003c\/p\u003e\n\u003ccenter\u003e\n\u003ch2\u003eBaader Red 610nm Long-Pass Filter Features...\u003c\/h2\u003e\n\u003c\/center\u003e\n\u003cul\u003e\n\u003cli\u003eFreedom from ghost images, even when stacked.\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003cul\u003e\n\u003cli\u003eStriae-free substrates are polished parallel to within 30 seconds of arc to avoid wedge errors.\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003cul\u003e\n\u003cli\u003eFinest 7-layer hard multi-coatings on both faces feature 0.25% residual reflections (Baader filters are unique, no other colored filter incorporates anti-reflection multi-coatings).\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003cul\u003e\n\u003cli\u003eExtremely high transmission results in maximum contrast and isolation of planetary details, even with smaller telescopes.\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003cul\u003e\n\u003cli\u003eEfficiencies of the three longpass filters (Red, Orange, and Yellow) peaks at 98%, and efficiencies of the three bandpass filters (Green, Blue, Dark Blue) achieve 70%.\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003cul\u003e\n\u003cli\u003eCarefully designed spectral characteristics. Filters may be stacked without image degradation or ghosting, in order to provide even narrower passbands. Or, combine with any of the other Baader filters for interesting possibilities.\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003cul\u003e\n\u003cli\u003eNo reduction in sharpness, even at high magnifications or when using the filter far ahead of the focal plane (ie, digital imaging, or in front of a diagonal or binoviewer).\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003ccenter\u003e\n\u003ch2\u003eBaader Red 610nm Long-Pass Filter Specifications...\u003c\/h2\u003e\n\u003c\/center\u003e\n\u003cp\u003eFilter Type: Red\u003c\/p\u003e\n\u003cp\u003eSize:  2\"\u003c\/p\u003e\n\u003cp\u003eBandpass: 610nm\u003c\/p\u003e\n\u003cp\u003eFormat: Round, Mounted\u003c\/p\u003e\n\u003cp\u003eThreaded: Yes\u003c\/p\u003e\n\u003cp\u003ePurpose: Visual and Photographic\u003c\/p\u003e\n\u003cp\u003eCoatings: Multi\u003c\/p\u003e\n\u003cp\u003eTransmission: 98%\u003c\/p\u003e","brand":"Baader Planetarium","offers":[{"title":"Default Title","offer_id":43911455441009,"sku":"BAA-FCFR-2","price":110.0,"currency_code":"CAD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0851\/2766\/files\/FCFR-2.webp?v=1786057033","url":"https:\/\/khanscope.com\/fr\/products\/baader-2-red-610nm-long-pass-filter-round-mounted-fcfr-2","provider":"Khan Scope Centre","version":"1.0","type":"link"}