A range of filters recommended for use either in front of or behind the lens. They control the spectrum by reducing the transmission at specific wavelengths. They are primarily used to colour balance films, the required filter being determined as a result of tests, or as specified by the manufacturer. They can also be useful for correcting light sources for which no one conversion filter exists, or for adding a deliberate colour bias. Cyan principally absorbs Red. Looking for the right Lee Filter for you? Use Lee’s System Match tool to find what’s compatible with your equipment.