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

Therefore we returned to the use of a special control unit built specifically for this operation. These units contained heavy-duty relays designed to control much higher currents than the camera would draw, and pneumatically controlled time-delay relays that were set to provide about 10% more than the calculated running time before shutting off the camera. No failures were experienced with this equipment. It is our belief that the longer focal length lenses provided for the Fastax camera should be examined for excessive change in focal point when subjected to a temperature change of, say, 30 F. The pictures taken with the 10-in. lens were out of focus, and this may have been caused by the temperature rise that occurred between the setting up of the camera and its operation. Should an examination prove the lens to be temperature sensitive, precautions could be taken to minimize the effect through a redesign of the lens or, if this is not possible, to protect it from changes in temperature. In a test operation of this magnitude that involves a coordination of the highspeed cameras with a considerable variety of other instrumentation, we suggest that all circuits to the camera be centralized in a special control panel on which signal lamps would be arranged to indicate at all times the condition of each circuit. In addition, apparatus for recording the instant of arrival of the trigger signal at the panel and the subsequent behavior of the circuits should be provided. Although one may be accused of gilding the lily, a means of remotely controlling the Fastax speed and iris settings would have made it possible to secure better pictures in a number of instances. To the best of our knowledge, no really good equipment is available for reading the films from the high-speed cameras. We have used the Bell & Howell 16mm time-and-motion study projector for some years, but it is not well suited to our needs. The apparatus we would like to have would possess the following features: 1. Ability to rotate the image 15° about the optical axis. 2. Ability to vary the magnification of the image continuously from 1 5 to 30 times. 3. Better framing, so that a minimum of adjustment is required to cause succeeding frames to coincide exactly on the screen, regardless of the direction in which the film has been moving. 4. Forward and reverse viewing down to 4 frames/sec in addition to single-frame projection. 5. The image should appear on a screen set into a horizontal working surface. The screen might well be set at a small angle, say 20°, to facilitate viewing from a seated position. The screen should be replaceable with a piece of clear glass to permit projecting the image directly on graph paper so that one can obtain a direct tracing of the image. 6. The illumination of the image should be high enough to permit tracing but adjustable by means of a diaphragm to a level comfortable for direct viewing on the ground glass. 7. The entire apparatus should not cost over $1500. In order to provide the facilities required to process the films obtained on this program, a darkroom was set up in an 8 X 8 X 24 ft trailer. Cabinets and counters of the type employed in modern kitchens were installed and a large sink was provided. In addition to these fundamental items, a small refrigerator for the purpose of storing film, a 35mm contact printer, and a Houston machine were installed in the other end of the trailer. This amount of equipment did not leave a great deal of space for the personnel, and it is our feeling that a somewhat larger trailer would have permitted a more efficient installation, although this arrangement was satisfactory. In connection with 416 Aprtt 1953 Journal of the SMPTE Vol. 60