Foma Variant Printing Filter Kit consists of 6 gelatin filters for use with variable-contrast B&W papers. Different grades can be achieved with this kit by combining different filters in order to adjust the desired contrast grade.
The filters are used either in the drawer of the enlarger or held under the enlarging lens. They should be either above the condenser, or directly under the lens in order to retain maximum sharpness.
The filters can be easily cut to other sizes with scissors or a paper cutter.