The STC low-light television camera with cover removed.
A television camera, type GTNV-1 capable of producing pictures from scenes illuminated at light levels equivalent to starlight, has been introduced by STC. Minimum scene-illumination requirement for the camera, is about 2 x 10-5 ft. candles so that it can respond to scenes that are invisible to the human eye. A vidicon tube is used in conjunction with a three-stage image intensifier having a very high overall gain. Typical brightness magnification is 35,000 times. No especially contrived illumination such as infra-red beams, or reliance on self-emitted infra-red is necessary. For use underwater, where there is very little light, a clearer picture is obtained by using the natural light available rather than an artificial source, the light from which tends to be scattered back to the camera and so degrading the picture.