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

must be fully resolved before standardization of magnetic tracks for TV station use can be accomplished. As has been pointed out, differential head wear can cause loss of contact between the head and the magnetic stripe. Stripes of varying thickness may reproduce poorly, if at all, and any considerable head grooving by narrow stripes running on full-width heads will eventually cause scratching of remaining photo-track areas. Combination photo-magnetic tracks (for 16mm release prints) are thus hardly a solution to the interim problem, and we do not feel that supplying magnetic tracks to some TV stations and photographic tracks to others is at all practical. Another consideration which should be investigated is the standardization of track advance for 16mm magnetic prints. The most obvious placement is making the magnetic track even up with the optical track. This places the magnetic pickup head at the sound drum, an unfortunate location in some projectors. The present 26-frame advance places severe mechanical restrictions on the design of projectors in that complete flutter isolation is usually hard to obtain. If more advance were used, better isolation could be obtained and easier threading of projectors and possibly a more optimum placement of the magnetic pickup head might result. While from mechanical considerations it might be worth while to increase the track advances this poses another serious problem. It is common practice to leave 1£ seconds ofc silent film on TV commercials now so that' they may be spliced head-to-tail withj other spots without cutting off the trackj The 36 frames of silent picture allow several splices to be made without coming too close to the track. If the track is advanced any further, more silent picture will have to be provided. The 1£ seconds already provided represent a considerable* proportion of the so-called "10 and 20second spots," and there probably would be* considerable opposition to providing additional silent frames. These problems, as well as other more* minor considerations I have not men-; tioned, deserve very serious attention before additional magnetic-track standards are set up. It would be most unfortunate were we to go ahead using a medium which offers such considerably improved 16mm sound film quality in TV without first establishing procedures and standards which will permit it to be realized. Furthermore, in our opinion equally serious industry consideration should be given by all concerned to setting up an eventual definite date for complete changeover to the exclusive use of magnetic sound tracks in TV stations. It might be a very expensive operation, but in the long run we feel that it would be by far the safest plan. GENERAL EDITORIAL COMMENT AND CURRENT STATUS REPORT By R. T. Van Niman Following the Washington convention, the Reeves Soundcraft Corp. paper on commercial striping experiences, the Bell & Howell Co. paper, the Minnesota Mining & Mfg. Co. paper, and the Eastman Kodak Co. paper were re-presented by their authors at the October 16, 1952, meeting of the SMPTE Central Section in Chicago. John K. Hilliard (Altec Lansing Corp., Hollywood), Chairman of the SMPTE Sound Committee, presided over the extensive discussion which followed. Much of this discussion duplicated that in Washington, and hence only non -duplicated items are summarized in these comments to conserve Journal space. Since Mr. D'Arcy could not be present due to illness, Mr. Hilliard opened the discussion period by abstracting Mr. D'Arcy's Washington paper on magnetic standardization needs. He pointed out that the "sub-subcommittee" on Magnetic Reproduce Characteristics headed by Mr. D'Arcy has the exceedingly important job of reconciling present differences in such matters to the end that magnetic sound tracks recorded on one make of equipment eventually will reproduce satisfactorily on equipment furnished by other manufacturers. Such standardization appears possible without seriously limiting advancement of the art, and it is being strongly urged by both industrial equipment users 532 April 1953 Journal of the SMPTE Vol. 60