{"product_id":"sodium-d-quantum-filters","title":"Sodium D Quantum Filters","description":"\u003ch1 class=\"has-link-color wp-elements-26731721d9341b5813d958f6670aadb5 wp-block-post-title has-text-color has-accent-2-color\"\u003eSodium D Quantum Filters\u003c\/h1\u003e\n\u003cdiv class=\"entry-content alignfull wp-block-post-content has-global-padding is-layout-constrained wp-block-post-content-is-layout-constrained\"\u003e\n\u003cspan id=\"more-336\"\u003e\u003c\/span\u003e\n\u003cp\u003eDayStar is proud to offer Sodium Na- D line (5895.9Å ) filtering systems. For visual and photographic studies.  Sodium filter assemblies are designed for sub-angstrom observations with single-cavity design. Sodium lines are very narrow, but very bright. A very narrow filter of \u0026lt; 0.5Å is necessary to properly isolate the line from the continuum. The resulting image depicts high detail in granulation, supergranulation and P-modes.\u003c\/p\u003e\n\u003cp\u003eSodium also shows impulsive-phase flare eruption kernels. Na D is a low excitation line emitted when the low chromosphere is heated, usually at footpoints of flux loops passing through a flare, as sodium D line reflects the lower chromosphere. Visual and photographic images reveal type image as Calcium, revealing granulation, but are much brighter and more easily visible.\u003c\/p\u003e\n\u003cdiv class=\"wp-block-columns is-layout-flex wp-container-core-columns-is-layout-28f84493 wp-block-columns-is-layout-flex\"\u003e\n\u003cdiv class=\"wp-block-column is-layout-flow wp-block-column-is-layout-flow\"\u003e\n\u003cp\u003eUniversity series filters are designed to operate unheated on the lower of the two Na D emission lines; and can be heated to accomplish transmission on the higher of the two Na D lines, making doppler studies possible by photographing in each line and deriving difference images after subtracting an average solar velocity image. This process is referred to as a dopplergram velocity image, reveals the surface motions associated with supergranulation.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"wp-block-column is-layout-flow wp-block-column-is-layout-flow\"\u003e\n\u003cfigure class=\"wp-block-image size-full is-resized\"\u003e\u003cimg class=\"wp-image-338\" src=\"https:\/\/cdn.shopify.com\/s\/files\/1\/0686\/0049\/6239\/files\/cur_dop_na1b_240d9212-dbdb-4fcf-983e-4da38250f851.jpg?v=1766573216\" sizes=\"(max-width: 200px) 100vw, 200px\" srcset=\"https:\/\/cdn.shopify.com\/s\/files\/1\/0686\/0049\/6239\/files\/cur_dop_na1b_240d9212-dbdb-4fcf-983e-4da38250f851.jpg?v=1766573216 200w, https:\/\/www.daystarfilters.com\/df\/wp-content\/uploads\/2025\/03\/cur_dop_na1b-150x150.jpg 150w\" alt=\"\" width=\"200\" height=\"200\"\u003e\n\u003cfigcaption class=\"wp-element-caption\"\u003eMount Wilson Solar Observatory\u003c\/figcaption\u003e\n\u003c\/figure\u003e\n\u003c\/div\u003e\n\u003c\/div\u003e\n\u003cp\u003eThese filters have until now been primarily used for research purposes only, performing doppler and supergranulation studies. Narrow bandpass Na D line filters have also been used in deep-sky observations of IO, but with significantly larger apertures.\u003c\/p\u003e\n\u003cmain id=\"wp--skip-link--target\" class=\"wp-block-group has-global-padding is-layout-constrained wp-block-group-is-layout-constrained\"\u003e\n\u003cdiv class=\"wp-block-group alignfull has-global-padding is-layout-constrained wp-block-group-is-layout-constrained\"\u003e\n\u003cdiv class=\"entry-content alignfull wp-block-post-content has-global-padding is-layout-constrained wp-block-post-content-is-layout-constrained\"\u003e\n\u003cdiv class=\"wp-block-columns is-layout-flex wp-container-core-columns-is-layout-28f84493 wp-block-columns-is-layout-flex\"\u003e\n\u003cdiv class=\"wp-block-column is-layout-flow wp-block-column-is-layout-flow\"\u003e\n\u003cfigure class=\"wp-block-image size-full is-resized\"\u003e\u003cimg class=\"wp-image-340\" src=\"https:\/\/cdn.shopify.com\/s\/files\/1\/0686\/0049\/6239\/files\/sodium_Swaim_wide_171824e0-2309-4ad1-b187-6fc4d163cd90.jpg?v=1766573218\" alt=\"\" width=\"237\" height=\"300\"\u003e\n\u003cfigcaption class=\"wp-element-caption\"\u003ePhoto by Greg Swaim\u003cbr\u003eDayStar Filters 0.4Å Sodium D line filter\u003c\/figcaption\u003e\n\u003c\/figure\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"wp-block-column is-layout-flow wp-block-column-is-layout-flow\"\u003e\n\u003cfigure class=\"wp-block-image size-full is-resized\"\u003e\u003cimg class=\"wp-image-341\" src=\"https:\/\/cdn.shopify.com\/s\/files\/1\/0686\/0049\/6239\/files\/sunspot_Sodium_0932_wide-1_c959e57b-1f5d-43a7-945f-43a3db757a53.jpg?v=1766573219\" alt=\"\" width=\"300\" height=\"263\"\u003e\n\u003cfigcaption class=\"wp-element-caption\"\u003eShort lived solar flare flashes in Na D line:\u003cbr\u003ePhoto by Greg Swaim\u003cbr\u003eDayStar Filters 0.4Å Sodium D line filter\u003c\/figcaption\u003e\n\u003c\/figure\u003e\n\u003c\/div\u003e\n\u003c\/div\u003e\n\u003cp\u003e\u003cstrong\u003e*\u003c\/strong\u003e\u003cbr\u003e\u003cstrong\u003eNote. These systems require an energy rejection pre-filter and F\/30 focal ratio for onband operation.  Standard yellow glass DayStar Energy rejection filters provide sufficient off-band energy rejection, as do dielectric ‘hot mirror’ coated pre-filters.\u003c\/strong\u003e\u003c\/p\u003e\n\u003cp\u003e\u003cstrong\u003e* HALF-BANDWIDTH:\u003cspan\u003e \u003c\/span\u003e\u003c\/strong\u003eThe term half-bandwidth refers to an optics industry standard of measure.  On a chart depicting the peak where light is transmitted, that peak’s width is measured at the point 50% between zero and full transmission. This term is called half-bandwidth.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003c\/div\u003e\n\u003c\/main\u003e\u003cfooter class=\"wp-block-template-part\"\u003e\n\u003cdiv class=\"wp-block-group has-global-padding is-layout-constrained wp-block-group-is-layout-constrained\"\u003e\n\u003cdiv class=\"wp-block-group alignwide is-layout-flow wp-block-group-is-layout-flow\"\u003e\u003cstrong\u003eDaystar Filters Quantum Filters are Special order only and are subject to the terms and conditions found here: \u003cspan\u003e \u003c\/span\u003e\u003ca href=\"%%GLOBAL_ShopPathSSL%%\/terms-policy\/\" target=\"_blank\" rel=\"noopener\"\u003e%%GLOBAL_ShopPathSSL%%\/terms-policy\/\u003c\/a\u003e\u003cspan\u003e \u003c\/span\u003ePre-Payment may be required.\u003c\/strong\u003e\u003c\/div\u003e\n\u003c\/div\u003e\n\u003c\/footer\u003e\n\u003c\/div\u003e","brand":"Daystar Filters","offers":[{"title":"0.4Å Single cavity Amateur T-Scanner filter system","offer_id":44014155628655,"sku":"7326-04","price":7679.99,"currency_code":"CAD","in_stock":true},{"title":"0.4Å Single cavity University series filter system","offer_id":44014155661423,"sku":"7326-04-1","price":12019.99,"currency_code":"CAD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0686\/0049\/6239\/files\/NAD.4UNI__75132.jpg?v=1766573221","url":"https:\/\/ontariotelescope.com\/products\/sodium-d-quantum-filters","provider":"Ontario Telescope and Accessories","version":"1.0","type":"link"}