Celestron RASA 8 Imaging Filter H-Alpha, H-Beta, Oxygen III Narrowband Filter Enhances Emission Nebulae

Bring out the best in your nebulae astroimages with the H-Alpha-H-Beta-OIII Imaging Filter for the 8 RASA. This specialized filter allows high transmission of light from emission nebulae while blocking light pollution and natural sky glow. This helps to make your images pop with detail off the black sky background with superior contrast. The Imaging Filter transmission spectrum is 85% or greater at key wavelengths (486nm, 496nm/501nm, 656nm) and less than 0.5% transmission elsewhere. These wavelengths will make emission nebulae like the North America Nebula (NGC 7000) and Lagoon Nebula (M8) shine with phenomenal detail. The H-Alpha-H-Beta-OIII Imaging Filter is a narrowband filter that blocks much of the visible spectrum and only allows specific wavelengths through. Because of this, it will not work well on broadband emission objects, such as galaxies and star clusters. This filter was custom engineered to work exclusively with the RASA 8 f/2 optical tube to ensure premium optical performance and that essential wavelengths reach your cameras sensor. The filter features a machined aluminum black anodized cell with knurled rim for easy grip during installation. An anti-reflection coating has been added to the filter to help suppress reflections on the glass. The filter fits directly into the internal filter mount in the RASA 8s front lens cell, where the optical window normally mounts. Each filter comes with a spectral transmission graph unique to your specific unit, verifying its performance.