Comparative Noise Properties of Vision, Television, and Photographic Film

Abstract

A television system is, for the most part, a surrogate for the human eye. The television camera in the studio or at some public event should be seeing what we, as viewers, would see if we were present. Consciously or unconsciously, we judge the quality of the transmitted picture in terms of what our own visual system would have apprehended when standing alongside the camera. For our purposes, this statement has particular meaning for those situations in which the camera is picking up scenes at low light levels, where the information transmitted is limited by the amount of light available. The television picture is then noise-limited as, indeed, our own visual system would be when viewing the original scene. The difference is that the television picture is presented at a high light level so that its noise is readily visible. Our own visual system in viewing the original scene would automatically adjust the gain of the visual process to make the noise only barely visible.