A note on controlling the optical density on analog film records in strong motion accelerographs

Abstract

A device and its solid state logic are described which improve the uniformity of the optical density of recorded analog traces on film. An example is presented for the Light Control Module LM-8, designed to work in the SMA-1 strong motion accelerograph. Tests have been performed to determine the overall performance of LM-8. The results are very favorable and show that LM-8 improves significantly the overall quality of strong motion acceleration traces recorded on film.