Improve the mapping of fog with your RASA 8 "astrographer by blocking light pollution, improving the image contrast and darkening the sky background. This filter only allows the most important H-alpha and H-beta-oii wave length of emission fogs and offers a high Contrast. This filter selectively blocks the wavelengths of the light of light sources that pollute the sky and natural lights of the sky. In contrast to similar filters with narrower band passes, this filter was specially developed for use with the fast F/2 optics fits. in the integrated filter holder of the 8-inch-RASA and ensures an optimal optical performance.
