It's an excellent high-contrast deep sky red filter for RGB use, optimised for all interline CCD chips. It allows CCD-contrast images of H II regions (e.g. North America Nebula) and images can be taken even from "light-polluted" areas.
It comes with a non-aging efficient hard coating on a planeoptically polished surface. Ideal for fast optical systems between f/10 and f/2.8.
It will cause NO haloes and NO reflections. According to the spectral analyse (please see the image below) IR is blocked as well.
