DISCUSSION ON ISSUES OF PHOTOGRAPHIC RECORDING AND REPRODUCTION OF SOUND

From June 26 to 28, 1950, in Leningrad, a regular plenum of the Commission on Scientific Photography and Cinematography of the Academy of Sciences of the USSR took place, devoted to a scientific discussion on issues of photographic recording and reproduction of sound.

The plenum was opened by the deputy chairman of the Commission, Corresponding Member of the Academy of Sciences of the USSR T. P. Kravets. In his introductory remarks T. P. Kravets gave a historical account of the fact that, even before the First World War, at the famous Lebedev Colloquium in Moscow, the Russian inventor S. Ya. Lifshits demonstrated modulation of light by means of a sinusoid cut out of opaque paper. T. P. Kravets then dwelt on the works of the remarkable Russian inventor and researcher A. F. Shorin, which testify to the priority of the Russian inventor of sound cinematography over foreign inventors.

A large report on the life and activity of A. F. Shorin—the major Soviet inventor in the field of sound cinematography—was presented by the closest collaborator of A. F. Shorin, engineer A. S. Polyansky. The plenum recognized the need to publish the complete text of A. F. Shorin’s autobiographical manuscript, which had been issued in 1949 by Goskinoizdat rather carelessly and in a considerably abridged form under the title How the Screen Began to Speak.

Prof. V. A. Burgov (Leningrad Institute of Motion-Picture Engineers) presented a report entitled “A Project for a Fundamental Improvement in the Quality of the Photographic Transverse Sound Track in the Mass Production of Films.” In his report V. A. Burgov analyzed the technology currently used in the film industry for the photographic processing of sound tracks and established the reasons for the insufficiently high sound quality of mass-circulation motion pictures. The speaker cited interesting data on research work in this field carried out by a group of engineers from Leningrad film enterprises (I. N. Aleksander, B. L. Brodsky, Prof. V. A. Burgov, A. I. Kalinikos, V. V. Rakovsky). Using a newly developed technique and apparatus for measuring nonlinear distortions in a sound track under dynamic conditions, they established the dependence of the optimum photographic processing on the transmitted sound signal and developed a rational method of photographic processing for transmitting the required broad range of sound frequencies. On the basis of an analysis of the mass production of films at film-copying factories, using methods of mathematical statistics, the conditions for a stable improvement in the sound quality of mass copies were established.

A considerable discussion developed around V. A. Burgov’s report. The plenum adopted a resolution noting the great production value of the work reported and recommending that the Ministry of Cinematography of the USSR introduce the new technology for processing sound tracks at all studios and copying factories of the Union.

In the report “Sound Track on Narrow Film,” engineer S. D. Karpidi described the work of the Scientific Research Institute of Cinema and Photography, which had provided for the intensive development of narrow-film sound cinematography. At the same time, the speaker pointed out the insufficiently high sound quality of narrow films, caused by the use of a countertype obtained by printing the sound track on a toothed drum, and by the use of negative and positive films with too low a resolving power and too coarse a grain.

In the discussion and in the resolutions of the plenum it was pointed out that it is necessary, on the one hand, to develop and apply new motion-picture films for sound recording with high resolving power (150–180 lines mm\(^{-1}\)), and, on the other hand, to develop and improve apparatus for printing a phonogram by optical means and for re-recording a phonogram onto narrow film. The plenum also noted the need to introduce into production mass printing of the phonogram from a 35-millimeter negative onto 16-millimeter film.

In his major report “Paths of Development of Light-Modulating Devices for Photographic Sound Recording,” Candidate of Technical Sciences A. M. Melik-Stepanyan (Leningrad Motion-Picture Apparatus Plant) gave a historical survey of the development and improvement of light-modulating systems. Particular attention in the report was devoted to the achievements of domestic motion-picture technology in creating a mirror galvanometer of the magnetoelectric type and light modulators for sound recording by the intensity method.

In its resolution the plenum of the Commission noted that the creation of the first domestic model of such a galvanometer, designed by A. M. Melik-Stepanyan and considerably superior in its characteristics to foreign models, is a major achievement of Soviet motion-picture technology.

The plenum adopted a general resolution stating that the state of the problem of photographic sound recording raises, with particular urgency, the question of the need to create specialized sensitometry of motion-picture films for sound recording as a quantitative method for assessing phonogram quality.

It was also deemed desirable to convene in 1951 a special meeting or conference on sensitometric questions of photographic sound recording.

I. N. Aleksander