Fifty years of the Lallemand electronic camera

A. Lallemand (1934) combined, in a single instrument, the properties of the photographic plate (large surface, large integrating time) and the efficiency of the photoemission (linear response to flux, good signal to noise ratio). The first experiments are recalled. The author describes the various developments that took place in France and other Countries during the last 50 years. He mentions also the original applications of the electronographic receivers to Astronomy.