{"product_id":"player-one-erf-filter-s-series-for-quark-chromosphere","title":"Player One ERF Filter S-series for Quark Chromosphere","description":"\u003cul class=\"DAV-feature-list\"\u003e\n\u003cli\u003eAvailable in 1.25\" and 2\" filter sizes\u003c\/li\u003e\n\u003cli\u003eEnergy Rejection Filter (ERF) for Quark Chromosphere\u003c\/li\u003e\n\u003cli\u003eDesigned for refractors up to 5\" (1.25\" version) or 6\" (2\" version) in aperture\u003c\/li\u003e\n\u003cli\u003eHigh-quality B270 optical glass substrate\u003c\/li\u003e\n\u003cli\u003eMulti-layer reflective coatings to prevent heat absorption\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\u003eERF Filter S-series for Quark Chromosphere\u003c\/h2\u003e\n\u003cp\u003eThe Player One ERF Filter S-series is a critical accessory for solar observers using a Quark Chromosphere H-alpha eyepiece on refractors up to 5\" (1.25\" version) or 6\" (2\" version) in aperture. Built on a B270 optical glass substrate, its advanced multi-layer coatings reflect harmful solar energy before it reaches the Quark, significantly reducing the heat load on your Quark's sensitive internal components.\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\u003eProtect Your Quark: Energy Rejection for Refractors up to 5\" or 6\"\u003c\/h3\u003e\n\u003cp\u003eA Quark Chromosphere's internal etalon and blocking filters are small. In refractors approaching the aperture limit, the focused solar disk can be larger than these internal filters, concentrating intense heat onto the filter assembly and its housing. The Player One ERF sits ahead of your Quark (the 2\" version threads onto the front of your diagonal), rejecting this thermal energy early in the optical path to protect your investment and extend the life of your Quark.\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\u003eReflective B270 Glass and Multi-Layer Coatings\u003c\/h3\u003e\n\u003cp\u003eUnlike simple absorptive filters that can heat up and degrade seeing, this ERF uses a reflective design. The multi-layer coatings are applied to a clear B270 glass substrate, a material known for its excellent optical transmission and stability. This construction ensures that unwanted energy is reflected away from the telescope, not absorbed into the filter glass, so the ERF itself remains cool.\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\u003eA Second Role: Enhancing Lunar Imaging\u003c\/h3\u003e\n\u003cp\u003eBeyond its primary solar function, this ERF serves as an effective filter for high-resolution lunar imaging. It can improve atmospheric seeing and boost contrast on lunar features. It provides a brighter image than a typical IR-pass filter like an IR685, allowing for shorter exposures and capturing finer detail along the terminator.\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\"\u003eWhy do I need the Player One ERF with my Quark Chromosphere?\u003c\/h3\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion-A\"\u003e\n\u003cp\u003eThe Player One ERF is designed to protect the small internal filters inside a Quark Chromosphere from concentrated solar heat. In a refractor, the focused image of the sun can be larger than these filters and heat the Quark's housing and internal components. This filter rejects that energy before it enters the Quark, extending its life.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion\"\u003e\n\u003ch3 class=\"DAV-accordion-Q\"\u003eWhich ERF size do I need for my refractor?\u003c\/h3\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion-A\"\u003e\n\u003cp\u003eThe \u003cstrong\u003e1.25\" ERF\u003c\/strong\u003e is intended for refracting telescopes up to 5\" (127mm) in aperture, and the \u003cstrong\u003e2\" ERF\u003c\/strong\u003e for refracting telescopes up to 6\" in aperture. Using either on a larger refractor or on any reflector-style telescope (like an SCT or Newtonian) is unsafe and can damage your equipment.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion\"\u003e\n\u003ch3 class=\"DAV-accordion-Q\"\u003eDoes the Player One ERF filter absorb a lot of heat?\u003c\/h3\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion-A\"\u003e\n\u003cp\u003eNo, it is a \u003cstrong\u003ereflective\u003c\/strong\u003e filter, not an absorptive one. It uses multi-layer coatings on B270 optical glass to reflect unwanted solar energy back out the front of the telescope. This design prevents the filter itself from heating up and becoming a source of heat in your optical train.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion\"\u003e\n\u003ch3 class=\"DAV-accordion-Q\"\u003eHow does the Player One ERF improve lunar imaging?\u003c\/h3\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion-A\"\u003e\n\u003cp\u003eFor lunar imaging, the filter acts to improve contrast and can help stabilize atmospheric \"seeing.\" It provides a brighter image than a standard IR685 filter, which allows for shorter exposure times. This helps you freeze moments of steady air to capture finer details on the Moon's surface, particularly along the terminator.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion\"\u003e\n\u003ch3 class=\"DAV-accordion-Q\"\u003eCan I use this ERF for solar observing without a Quark?\u003c\/h3\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion-A\"\u003e\n\u003cp\u003e\u003cstrong\u003eABSOLUTELY NOT.\u003c\/strong\u003e This is an energy rejection filter, not a standalone full-aperture solar filter. It must be used in conjunction with a Daystar Quark Chromosphere. Using it alone for any kind of solar observation will cause immediate and permanent eye damage and can destroy your equipment.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion\"\u003e\n\u003ch3 class=\"DAV-accordion-Q\"\u003eWhere do I place the Player One ERF in my optical train?\u003c\/h3\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion-A\"\u003e\n\u003cp\u003eFor maximum effectiveness, the ERF should be placed as early in the optical path as possible, ahead of your Quark. The most common placement for the 2\" version is to thread it onto the 2\" nosepiece of your star diagonal. This ensures that the bulk of the solar energy is rejected before it enters the diagonal and reaches your Quark.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003c\/li\u003e\n\u003cli\u003e\n\u003ch3\u003e1.25\"\u003c\/h3\u003e\n\u003ctable class=\"DAV-specifications\"\u003e\n\u003ctbody\u003e\n\u003ctr\u003e\n\u003ctd\u003eFilter Size\u003c\/td\u003e\n\u003ctd\u003e1.25\"\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eFilter Type\u003c\/td\u003e\n\u003ctd\u003eEnergy Rejection Filter (ERF)\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003ePrimary Application\u003c\/td\u003e\n\u003ctd\u003eDaystar Quark Chromosphere (H-alpha)\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eAperture Limit (Solar)\u003c\/td\u003e\n\u003ctd\u003eFor refractors 5\" or smaller\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eSubstrate\u003c\/td\u003e\n\u003ctd\u003eB270 Optical Glass\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eCoatings\u003c\/td\u003e\n\u003ctd\u003eMulti-layer reflective coatings\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eSecondary Application\u003c\/td\u003e\n\u003ctd\u003eLunar Imaging\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003c\/tbody\u003e\n\u003c\/table\u003e\n\u003ch3\u003e2\"\u003c\/h3\u003e\n\u003ctable class=\"DAV-specifications\"\u003e\n\u003ctbody\u003e\n\u003ctr\u003e\n\u003ctd\u003eFilter Size\u003c\/td\u003e\n\u003ctd\u003e2\"\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003ePrimary Application\u003c\/td\u003e\n\u003ctd\u003eEnergy Rejection for Quark Chromosphere\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eTelescope Compatibility\u003c\/td\u003e\n\u003ctd\u003eRefractors up to 6\" aperture\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eGlass Substrate\u003c\/td\u003e\n\u003ctd\u003eB270 Optical Glass\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eCoating Type\u003c\/td\u003e\n\u003ctd\u003eMulti-layer composite reflective coating\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eSecondary Application\u003c\/td\u003e\n\u003ctd\u003eLunar Imaging Enhancement\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\"\u003eERF Filter S-series (selected size)\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\u003cp\u003e\u003ca title=\"Player One 2-Year Warranty\" href=\"https:\/\/davidastro.com\/pages\/player-one-warranty-policy\" target=\"_blank\"\u003ePlayer One 2-Year Warranty\u003c\/a\u003e\u003c\/p\u003e\n\u003c\/li\u003e\n\u003c\/ul\u003e","brand":"Player One","offers":[{"title":"1.25\"","offer_id":52913425875229,"sku":"POA-ERF125","price":49.0,"currency_code":"USD","in_stock":true},{"title":"2\"","offer_id":52913425907997,"sku":"POA-ERF2","price":89.0,"currency_code":"USD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0753\/5280\/1565\/files\/PlayerOne-ERF-1-25-Filter-S-series-for-Quark-Chromosphere-1_4f7a0fbe-1223-4a2c-9718-e74d691c41a6.jpg?v=1789090916","url":"https:\/\/davidastro.com\/fr-us\/products\/player-one-erf-filter-s-series-for-quark-chromosphere","provider":"David Astro","version":"1.0","type":"link"}