Comprehensive Solar Protection: Specifically designed to safeguard your telescope and solar imaging equipment from excessive heat during solar observation with Daystar Hydrogen Alpha Quark or similar filters.
TRIBAND Pre-Filter: Combines Hydrogen Alpha, Calcium K-Line, and H-Line in one filter, optimizing solar imaging and saving costs on additional filters.
Specialized Coatings: Blocks Infrared, Ultraviolet light, and unwanted solar emission spectra, transmitting only the desired wavelengths for sharp solar imaging.
Precise Bandpass Control: 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.
Individual Spectrographic Report: Each filter includes a spectrographic test report corresponding to its serial number, guaranteeing quality and performance.
Versatile Holder Cell: 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.
Durable and Safe Design: 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.
Essential for Safe Solar Imaging: Must be used alongside a professional Etalon product with built-in blocking filters, such as the Daystar Quark, to prevent serious eye damage.
Heat Reduction: Reduces about 98% of heat reaching the optics, preventing off-band drift and protecting your equipment.
Enhanced Imaging Quality: 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.
Equipment and Etalon Protection: Prolongs the life of your equipment and Etalon by reducing the impact of heat and preventing potential fire hazards.
Ultra Narrow Band Transmission: 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.
IMPORTANT SAFETY INFORMATION: 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.
Easy Maintenance: Includes instructions for safely cleaning the D-ERF, ensuring long-term performance and protection of the coatings.
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