The 4 x 5.65" Color Graduated Plum 3 Filter from Formatt is one of the most widely used category of filters. It enhances reality, adding a touch of subtlety or drama to the image.
A Graduated Plum 3 filter is the most intense version of this filter. It differs from a Graduated Magenta that produces a milder purplish/red tint.
Often it is necessary or desirable to balance the light intensity in one part of a scene with another. This is especially true in situations where you don't have total light control, as in bright contrasty landscapes.
Sometimes it is also desirable to add color to part of the photograph. For example, to add blue to only the sky. Formatt Color Graduated filters are half-color, half-clear, with a graduated transition for blending into the scene. They are available in an array of colors. Soft/hard indicates the degree of transition. Horizontal/vertical indicates the direction of the transition.
Formatt square and rectangular filters are made from sheets of CR39 Resin sandwiched between two sheets of high-quality Schott glass. The reputation of Schott glass precedes itself and is world renowned. The dyes used are carefully manufactured and controlled and when sealed between the glass, become color consistent filter to filter. For the photographer/videographer/cinematographer, this means you can change filters from day to day or shot to shot knowing that your color consistency will be maintained.