This page last modified 2011 December 19

Colour Filters for Astronomy

Red Orange Yellow Green Blue Violet
Sun  Use with mylar solar filter to restore colour
Moon  Dark Red (#29) is better than a neutral density filter for visual lunar observation Greatly enhances features
Mercury  Reduces sky brightness during daylight and twilight observations Reduces sky brightness during daylight and twilight observations Reveals some surface markings at twilight Enhances faint features
Venus  Use during daylight to reduce sky brightness Use during daylight to reduce sky brightness Reveals some surface features Reveals cloud patterns Reveals some cloud detail Improves cloud contrast
Mars  Enhances polar caps Darkens maria and canali Darkens maria and canali Increases contrast of polar caps and dust storms Improves polar caps and some surface features Improves polar caps
Jupiter  Enhances detail in belts and festoons General enhancement of surface detail Improves contrast of Great Red Spot General enhancement of red belts and Great Red Spot
Saturn  Enhances bands General enhancement and clarifies Cassini's division Enhances low-contrast features Enhances detail in the rings
Uranus  Shows some detail in large telescopes (>250mm)
Neptune  Shows some detail in large telescopes (>250mm)
Comets  Enhances dust tails Can reveal some structure in brighter comets Increases detail in ion tails Can reveal some detail in bright comets
(Notes)  Do not use on small telescopes (<150mm)