Due to its light pink color, the B&W 34mm (KR 1.5) Digital Pro Skylight Glass Filter reduces the blue cast of daylight and produces a pleasing, warmer picture tone. Also known as a Skylight (1A) filter, it is a wise initial investment. It can help protect your lens from dust, moisture and scratches, which can lead to costly repairs.
B&W Digital Pro filters are characterized by a brushed chrome brass ring that will stylishly blend with today's modern digital cameras for both still and video formats.
If desired it 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 and videotape as a bluish cast and can obscure distant details
Also used to reduce the bluish cast common with some electronic flash units