{"product_id":"altair-astro-90mm-aperture-triband-d-erf-solar-energy-rejection-filter-h-alpha-cak-cah-95mm-glass","title":"Altair Astro 90mm Aperture TRIBAND D-ERF Solar Energy Rejection Filter - H-Alpha CaK CaH (95mm Glass)","description":"\u003cp\u003e\u003cstrong\u003eAltair Astro 90mm Aperture TRIBAND D-ERF WITH COVER\u003c\/strong\u003e\u003c\/p\u003e\n\u003cul\u003e\n\u003cli\u003e\n\u003cstrong\u003eComprehensive Solar Protection\u003c\/strong\u003e: Specifically designed to safeguard your telescope and solar imaging equipment from excessive heat during solar observation with Daystar Hydrogen Alpha Quark or similar filters.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eTRIBAND Pre-Filter\u003c\/strong\u003e: Combines Hydrogen Alpha, Calcium K-Line, and H-Line in one filter, optimizing solar imaging and saving costs on additional filters.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eSpecialized Coatings\u003c\/strong\u003e: Blocks Infrared, Ultraviolet light, and unwanted solar emission spectra, transmitting only the desired wavelengths for sharp solar imaging.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003ePrecise Bandpass Control\u003c\/strong\u003e: Features a 30nm FWHM Bandpass for both Ha and Calcium wavelengths, ensuring excellent contrast and effective blocking. Transmission rates are approximately 95% for Ha and 90% for Calcium peaks.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eIndividual Spectrographic Report\u003c\/strong\u003e: Each filter includes a spectrographic test report corresponding to its serial number, guaranteeing quality and performance.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eVersatile Holder Cell\u003c\/strong\u003e: The 120mm D-ERF filter element is secured in a holder cell with a 115mm clear aperture, fitting most 4-4.5\" refractors, including Altair's 102mm and 115mm range.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eDurable and Safe Design\u003c\/strong\u003e: The holder cell, made from UV resistant plastic with embedded aluminium flakes, ensures no pressure on the optics, preventing distortion and protecting the filter glass from breakage.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eEssential for Safe Solar Imaging\u003c\/strong\u003e: Must be used alongside a professional Etalon product with built-in blocking filters, such as the Daystar Quark, to prevent serious eye damage.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eHeat Reduction\u003c\/strong\u003e: Reduces about 98% of heat reaching the optics, preventing off-band drift and protecting your equipment.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eEnhanced Imaging Quality\u003c\/strong\u003e: By reflecting heat before it enters the telescope, the D-ERF leads to sharper images without heat haze from air currents inside the telescope tube.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eEquipment and Etalon Protection\u003c\/strong\u003e: Prolongs the life of your equipment and Etalon by reducing the impact of heat and preventing potential fire hazards.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eUltra Narrow Band Transmission\u003c\/strong\u003e: Allows the use of ultra narrowband Etalons like the Daystar Quark Chromosphere for longer life, thanks to modern coating methods blocking UV and IR light efficiently.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eIMPORTANT SAFETY INFORMATION\u003c\/strong\u003e: An ERF is a pre-filter and should only be used with a proper commercial Etalon with full blocking filters. Never use the ERF alone for solar observation.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eEasy Maintenance\u003c\/strong\u003e: Includes instructions for safely cleaning the D-ERF, ensuring long-term performance and protection of the coatings.\u003c\/li\u003e\n\u003c\/ul\u003e","brand":"Altair Astro","offers":[{"title":"Default Title","offer_id":52008181137728,"sku":"AA95ERFx8-103OD-TRIBAND-COVER","price":599.0,"currency_code":"USD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0717\/9904\/6464\/files\/altair-115mm-aperture-triband-h-alpha-cak-d-erf-120mm-filter-with-housing-cell-12458-p.jpg?v=1709148869","url":"https:\/\/astroworldtelescopes.com\/products\/altair-astro-90mm-aperture-triband-d-erf-solar-energy-rejection-filter-h-alpha-cak-cah-95mm-glass","provider":"Astroworld Telescopes","version":"1.0","type":"link"}