Pentax 67mm #25 Red Filter

R-2 (R60), Medium Red (25) Use with panchromatic or infra-red films to achieve maximum contrast. This filter will create dramatic sky effects, simulating moonlight scenes in mid-day by slight under-exposure. Cuts through fog, haze and mist by absorbing excessive blue and ultra-violet light rays. Excellent copying filter for blueprints. Primary use black and white film. Exposure Factor 6.