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

In the center is one of the three 35mm cameras installed about a year ago to accomplish the three-hour delay recording to be described here. It is to be noted that the 35mm camera is equipped with a 3000-ft magazine, permitting a running time of 33 min. The 35mm cameras used thus far have been of the "silent" type; that is, they record only the picture portion of the program. It is expected that single-system 35mm cameras capable of recording both picture and sound will soon replace the silent cameras shown here. The sound portion of the program is currently being recorded very successfully on 1 6mm perforated magnetic film, running at the 1 6mm speed of 36 fpm. For this purpose, two rack-mounted, synchronously driven RCA magnetic recorder-reproducers are employed. Two RCA 16mm optical recorders which have been modified by the addition of a recording head and a monitor head may also be used to perform magnetic recording. Lip synchronization between picture and track is cued by insertion of an audio tone in both picture monitor and sound recorder, thereby creating easily recognizable patterns comparable to studio slating marks. It has been the experience of broadcasters for many years that a small investment in an extra copy of a disc or tape is amply repaid because some accident may damage the "A" copy recording. This same philosophy applies to kinescope recording: hence most companies make two negatives, one being considered the "A" copy, the other the protection, or "B" copy. It is in this quick kine "B" copy operation that NBC's single-system, 16mm cameras are particularly useful, for they permit the recording of both a picture negative and a photographic, variable-area, directpositive, sound track on one, single-perforated strip of film. At the end of each half-hour of quick kine recording, both the 35mm and 16mm magazines are immediately removed from the cameras and taken into the darkroom for unload ing. It is to be noted that only two and a half hours now remain till the film must be processed, edited, and in the projector, ready to be rebroadcast to the west coast audience extending from San Diego to Seattle. The 16mm single-system "B" copy is developed by NBC personnel in one of two Houston Model 22 processing machines. A half-hour program requires about 45 min for complete processing, including a waxing treatment to enhance projection. Meanwhile, the 35mm "A". copy negative has been placed in its original light-tight carton, and handed to a waiting messenger who drives a few blocks across town to a commercial film laboratory where a crew is prepared to process the film immediately. Since the film used for the kine camera negative is actually a low-contrast positive, it runs through positive developer at the normal machine speed of 125 fpm, resulting in a negative gamma of about 1.60. It therefore creates no special problems, such as changes in machine speed or threading, and can be connected directly to other positive work going through the machine. After the film passes through developer, hypo and wash, it receives a waxing treatment which lubricates the film to permit immediate projection. Approximately one hour after the 2700-ft roll of undeveloped film reaches the laboratory, it comes off the dry end where the messenger is waiting to return it to the television station for editing. During the time the two negatives are being developed, the editing personnel are not idle. With the aid of a magnetic sound reader, the synchronization tonebursts at the head and tail of the 1 6mm magnetic film are located and marked with a wax pencil . Identification leaders are prepared in advance and attached to the All-Purpose Film Leader which has replaced the Academy leader for television films. The 16mm single-system "B" copy negative then arrives from processing, and is made ready for projection by the addition of the prepared Ralph E. Lovell: Kinescope TimeZone Delay 237