The Surveyor lunar landing television system

The slow-scan television camera used in Surveyor I operates in a slow-scan mode that reduces the RF power requirements for the lunar distances involved. One 600-television-line frame is provided every 3.6 seconds in normal operation; one 200-line frame every 60.8 seconds in a second mode of operation. Upon command from earth, the camera´s shutter opens, allowing light energy to reach a vidicon image sensor. The vidicon transduces the light energy to electric signals for subsequent transmission to earth. Detailed calibration information obtained prior to launch permits the correction of images received for geometric nonlinearities and distortions, frequency or aperture response, photometric nonuniformities, and coherent noise.