This red filter is ideal for strong contrast improvement since it absorbs green and blue completely and enhances red. Clouds are dramatically improved almost to the mood of a thunderstorm. It is more effective in cutting through haze, and moonlight effects are easily accomplished. It is also suited for infrared photography.
Lee gelatin filters are available in 3 x 3" (75 x 75mm), 4 x 4" (100 x 100mm).
Filter factor is 8 (+3 stops)
Reviews LEE Filters 3x3" Red #25 Polyester Filter for Tricolor/Color Separation Work