The 4 x 4" 100mm #25 Red Tricolor Wratten 2 Optical Filter from Kodak is designed to separate tones, build contrast and alter the color wavelength of light.
The filter absorbs blues and greens and enhances reds, which is useful for infrared or landscape photography. Skies become more dramatic and the infrared effect becomes greater. It has a filter factor of eight, so exposure must be increased by three stops to compensate.
The new and improved Wratten 2 filters are more rigid and durable than previous versions, and the colors are more resistant to fading and degradation. Fingerprints and smudges are easily removed, the filters are less sensitive to humidity, and less prone to static cling.
