Schneider Optics Sapphire Blue is a rich indigo blue solid color Sapphire Blue filters can be used to create cool or even cold feeling images. They can also be used to enhance blue of sky and water or for a moonlit "day for night" effect. Note that the filter color MIXES with the sky or water color to create the final color.
This filter is available in strengths of 1, 2, and 3. These strengths achieve a subtle, moderate, or bold effect.
Schneider makes both soft-edge(SE) and hard-edge(HE) Graduated Color filters. Typically, soft-edge filters are used with wide to medium-angle lenses because these lenses have greater depth of field. Hard-edge filters are preferred for use with telephoto lenses or for bold transitions.