Astro-Tech #21 Orange 1.25" color filter

Recommended applications for this filter:
Moon - Very useful for improving contrast between lunar features in scopes 6" and larger, with or without polarizer or neutral density filter. Mercury - Darkens terrestrial sky during daylight viewing to enhance rarely visible subtle surface albedo differences. Venus - Darkens terrestrial sky during daylight viewing to show the phases more clearly. Mars - Increases the contrast of polar caps, frost areas, low clouds, and dust storms against the ochre deserts. Also sharpens the boundaries of yellow dust clouds. Jupiter - Brings out structure in the belts and enhances festoons and polar regions. Saturn - Improves the structure of atmospheric bands and highlights blue-toned polar regions. Comets - Can be piggybacked with #38A filter to improve contrast of orange Sodium D lines in comet gas tails in scopes 10" and larger. Enhances the definition of comet heads and dust tails in 10" and larger scopes. Solar - Used to give correct color rendition of the Sun when using a Mylar solar filter.
46% transmission