Excerpt from Journal of the Society of Motion Picture Engineers, Vol. 46: January, 1946 Summary. Variable-density sound film recording is subject to intermodulation distortion in the low-frequency band which extends from the lower limit of the audible spectrum toward zero, but t to zero frequency. This distortion is the result of the Bromide Drag phemen and is in the nature of exorbitant gamma. Cor rections may be made for gamma at any point in this exorbitant range, but only at the sacrifice of correct gamma for other frequencies. About the Publisher Forgotten Books publishes hundreds of thousands of rare and classic books. Find more at www.forgottenbooks.com This book is a reproduction of an important historical work. Forgotten Books uses state-of-the-art techlogy to digitally reconstruct the work, preserving the original format whilst repairing imperfections present in the aged copy. In rare cases, an imperfection in the original, such as a blemish or missing page, may be replicated in our edition. We do, however, repair the vast majority of imperfections successfully; any imperfections that remain are intentionally left to preserve the state of such historical works.