Motion Picture Herald (Jan-Mar 1954)

To enable projectionists to keep 3D films in synchronization the Polaroid Corporation, Cambridge, Mass., has developed the equipment shown here. The "3D Sync Monitor" (above) detects small missynchronizations by the variation in strobe stripes visible through the view window and larger sync errors by means of the "tell-tale" filter mounted at the top of the unit. To be used in conjunction with the monitor is the "3D Sync Control" (below) which is wired between the selsyn motors of the two projectors. It permits the projectionist to make relative adjustments in the projectors in 1/6 frame steps by turning the switch in either direction, depending upon which projector is leading the other. When the strobe stripes in the monitor line up, the picture is in pe-fect sync. . . . its progress and its prospect First of the “new techniques,’’ third-dimension has survived abuses of hasty production and technical inexperience to continue its trial with greater promise than ever in product and implements. stereoscopic pictures for theatrical entertainment have had a year of trial. That hasn’t been much time. Nevertheless, the intricate technique of 3D cinematography and projection, with its strange demand of the public to collaborate in the process of exhibition, has vigorously survived to attract and please large audiences today, and to sustain serious pursuit of further technical progress. That summation jibes with the facts much better than opinion that the trial has been a failure. Theatres throughout the nation and beyond it this January are presenting a sizable group of 3D productions with the kind of box-office effect which some linguists of the business call socko. Some of these productions are also being shown 2D — and the 3D versions are marking up heavier grosses in many areas. “ ‘Hondo’ on Way to New 3D Records,” said a recent trade headline. Approval of both public and critics are similarly reported for “Cease Fire,” “Kiss Me Kate,” “Miss Sadie Thompson,” and the others. These productions display the better tools and greater savvy acquired at the studio end in the adaptation of cinematography to stereoscopy. It was to be expected that the first batch of 3D features would allow unfamiliarity with the medium and makeshift equipment to show through. The marvel is that studio technicians implemented them fast enough to establish the tremendous gap that lies artistically and technically between the early productions and those on theatre screens today. But significant work is being done to remove difficulties in exhibition which so long conspired with production crudities to make the trial of 3D unfair. There already are two systems for placing the disparate images on a single film, and sufficient prog ress is authoritatively reported on the vectographic method to give assurance of its ultimate feasibility for theatrical motion pictures. In the meantime, the effective 3D product available need not suffer from the twostrip method with synchronized projectors. It is estimated that some 5,000 theatres in the United States alone are equipped for 3D projection, and others are joining them, with the rate of installation possibly to be accelerated under the encouragement of the new 3D product. More experience and better equipment installations in projection rooms now can remove defects which have been blamed arbitrarily on the two-strip system. Stereoscopic projection was handed to projectionists with amazing confidence in their ability to understand mysteries only half explained. Certain mechanics of the process seemed simple enough ; but just how delicate was the relationship between two projection systems operating in synchronization was pretty much left to the ordeal of trial and error. Films out of sync as little as three-quarters of a frame disturb fusion of the images enough to reduce the effect of depth and to set up severe eye strain. “Yeah, now you tell me!” many a projectionist has muttered disgustedly, and with good reason. In some cases, the projector hookup couldn’t maintain required synchronization even when the two mechanisms were threaded properly. Synchronization also has been simplified to the point of positive control throughout the projection of a two-strip picture by doing nothing more than turning a knob, The Polaroid Corporation has developed an electronic monitor which reveals an outof-sync condition automatically, and a control which permits the projectionist, merely by actuating a switch, to bring the two 12 MOTION PICTURE HERALD, JANUARY 9, 1954