Integrating T.V. System Development at Cambridge

Abstract

The development of an integrating television system was started at Cambridge at the beginning of 1974, and is now nearing completion. It is intended to use the camera for accurate two — dimensional multi-colour photometry of galaxies and nebulae. The camera uses an SIT-vidicon and is a development of the work of Westphal at Caltech [1]. It differs in that the control of the camera and the reduction of the observations is handled by a small computer. The use of a computer gives a great deal of flexibility in operation, enabling the geometric (electro-optical) distortion in the camera tube to be corrected for with accuracy. It allows a number of housekeeping-type checks to be made on the operation of the camera (such as camera temperature, signal line noise levels and EHT supply levels) which would make any hand-wired controller extremely complex. The data are recorded on magnetic tape in digital form. A medium-persistence oscilloscope is used to display the data from the camera. A core image is held packed in bytes which provides a continuously refreshed image at about four frames per second fully interlaced. Images or parts of images may be displayed directly from the camera (when it is used for focussing or field finding) or from images stored on magnetic tape.

This work has been supported in part by the Royal Society and the Radcliffe Trustees