35mm Red Light Cameras
Some red light camera systems use 35mm film cameras. Similar to most 35mm cameras, these red light cameras are built to withstand a variety of temperatures and operating conditions. It must use wet film designed exclusively for traffic photography. The film may be color, black & white or infra-red based. Black & White photos are less expensive, however have the downside of not always clearly showing which light is illuminated on the traffic signal. Color photos are much more definitive. The ASA range can be from 25 to 1600. The number of exposures can range from 12 to 800. Film must be easily loaded and secured inside the camera by a single lever mechanism regardless of the type of film being used (including standard and bulk film). The camera must be capable of very high shutter speeds (1/1000th of a second) and also be able to take photos at two frames per second at minimum. Film from the 35mm red light cameras is collected regularly, depending on the average activity of the particular intersection. In most cases, daily. The film is transported for processing, developed, reviewed thoroughly and finally converted to a digital image.