The art of sound pictures (1930)

SOUND TECHNIQUE 231 of the old problems of photography are being repeated in a new form here. Just as natural colors fail to reproduce their relative values when translated into black and white, so with natural sounds. This means that many ingenious minds must work out a multitude of tricks in order to produce the effect of reality. As for the writer of the story, he should feel free to use any sounds which will intensify drama or character as well as the reality of the setting. For the next few years, he will probably be rebuffed by producers, who will tell him that some of these sounds cannot be reproduced. His answer at this point should always be: “Get busy and learn how to reproduce them.” PROJECTION So far, we have dealt with the various methods by which sound is photographed or recorded on vitaphone discs. We have now to explain how these photographic records of sound are translated back into audible sound waves in the motion picture theater. You will remember that our first problem was the translation of air waves of sound into electric currents, and thence into ether waves capable of being recorded on a sensitized film. We now find ourselves confronted with the problem of reversing this entire process. We have to start with light waves, governed by the photographic record, which must be translated into sound waves. The process of photographing sound involves the transforming of gross air waves into fine ether waves. Now, the next problem is the process of transforming fine ether waves into coarse or gross air waves. Both of these processes require the intermediate step of transformation