B+W 58mm Dark Red (092) Infrared Filter

The B+W 58mm Dark Red (092) Infrared Filter, which looks dark purplish red when held in front of a light source, blocks visible light up to 650 nm and passes only 50% of the radiation just below 700 nm (thus the dark red colour). From 730 nm to 2000 nm, transmission is greater than 90%. This makes photographs of pure red and infrared images possible with the best utilisation of the relatively low sensitivity of infrared films. As the sensitisation of infrared black-and-white films barely extends beyond 1000 nm, the red portion that is transmitted still makes a relevant contribution to the exposure. That is why this filter is the preferred filter for pictorial photography on IR black-and-white film. Its filter factor is 20 to 40.