Due to its light pink colour, the Hoya Skylight (1B) filters reduce the bluish cast of daylight & produces a pleasing, warmer picture tone. Wise initial investments, they help protect your lens from dust, moisture & scratches, which can lead to costly repairs. The Hoya 52mm HMC Skylight 1B Filter reduces the excessive bluishness that frequently occurs in outdoor colour photography, especially in open shade under a clear, blue sky. Multicoated to minimize reflection at the filter surfaces which reduces flare & ghosting. If desired they can be left on at all times for protection Skylight filters provide additional benefits of correction for Ultraviolet (UV) light which can register on film & videotape as a bluish cast & can obscure distant details Also used to reduce the bluish cast common with some electronic flash units Reduces the excessive bluishness that frequently occurs in outdoor colour photography, especially in open shade under a clear, blue sky; Also keeps skin tones free of colored reflections from nearby objects such as the shade of trees The absorption peak is in the range which corresponds to the film's green spectrum; This means outstanding outdoor shots with superb colour balance & clarity under all conditions