Journal of the Society of Motion Picture and Television Engineers (1950-1954)

picture and synchronizer signals. The type of modulation used in the aural transmitter shall be frequency modulation, the frequency deviation for 100% modulation shall be ±25 kc. The polarization of the transmitted radio wave shall be horizontal. Theater Television Theater Television Projector Installations. The number of theaters equipped with theater television projectors doubled during 1952. Approximately 50 installations were made, bringing the total number of theaters so equipped at the end of the year to 103. Theater Television Showings. During 1952 there were five theater television shows which were distributed on a nationwide basis. Two of these were prizefights, these being the MarcianoWalcott and Maxim-Robinson contests. Theater television was used for the first tune in 1952 for the distribution of a production of the Metropolitan Opera, the opera Carmen, which was shown in 31 theaters in 26 cities on December 11. Theater television was also used for the first time for a national sales meeting, the sponsor being Lees Carpets. The public service potentialities in theater television were shown in a program carried by the Federal Civil Defense Administration for the instruction of its workers in various cities. Eidophor. 1952 marked the first semipublic showings of the new Eidophor theater television projection system.36 During June of 1952 the Twentieth Century-Fox Film Corp. gave some twenty-five formal shows in its 300-seat theater at its home office building, 444 W. 56 St., New York. Some 3000 persons viewed these showings including the FCC, members of the Armed Forces, and other Government groups, as well as a complete cross section of management of the various segments of American industry. These shows were in full color using the field sequential (CBS) system. The technical standards employed were 25 frames/sec., 525 scanning lines with 2 to 1 interlace, a 12-mc video bandwidth, a 12 by 15-ft picture, and 5-ft-c highlight "brightness. Theater Television FCC Proceedings. The long-delayed theater television proceedings before the FCC commenced in October of 1952. In these proceedings the motion-picture industry is making its request for an allocation of channels in the microwave portion of the spectrum for the transmission of theater television programs from the point of origin to the various theaters. During the October session of the hearings, approximately two weeks were devoted to the presentation of the technical phases of the industry's case. This portion of the case was prepared jointly by the Motion Picture Association of America and the National Exhibitors Theatre Television Committee. The hearings were to be resumed in January of 1953. Of particular interest are certain technical proposals which were made by industry representatives at the hearings and which are summarized below: I. Video Signal Standards A. Video Bandwidth. The proposed video bandwidth is 10 me. This is based upon the requirement that theater television picture definition equal that of standard 35mm motion-picture film. In making this calculation, it was assumed that something in the order of 725 scanning lines might be required to reduce the visibility of the lines in a highdefinition system to a tolerable value. It was also assumed that either the field sequential color system or some system similar to that being developed by the National Television Systems Committee employing mixed highs and color subcarrier transmission might be used. B. Signal-to-Noise Ratio. The required signal-to-weighted-noise ratio required for monochrome transmission is 46 db, and for field sequential color is 42 db. The weighting factor discriminates against the higher video frequencies, tak 546 May 1953 Journal of the SMPTE Vol. 60