International projectionist (Jan 1963-June 1965)

Sound Track by J. G. Jackson College Boasts Modern Projection Room Nashville, Tenn. Dear J. G.: I'm told that light inbalance is mainly caused by using projectors of different makes or models. Does this always occur? Ralph Agar Dear Ralph: The use of different makes or models of projector mechanism on the two machines does not necessarily cause an inequality of screen-light balance, but whenever a light mismatch is obtained from a hybrid installation, do not fail to check the size of the openings in the shutter case and heat shield of the "dim" machine. It may be that these openings are too small to allow the light beam to pass through the aperture unobstructed. An obstinate case of brightness mismatch may require a recheck of the reflectance of the lamp mirrors and even if the angular width of the shutter blades in each of the projectors. Remember, it is the angular width of the shutter blades in degrees that affect shutter light transmission, not the actual size or diameter of the shutter in inches. Angular width, which should be exactly the same for the shutters of both projectors, is measured with a protractor, obtainable at almost any dime-store stationery counter. Because the optical plate glass in the projector ports may absorb 8 or more per cent of the light, a noticeable brightness mismatch will occur if the glass is present in one of the ports and absent from the other. The average observer is able to detect a brightness difference in the neighborhood of 4 or 5 per cent. More subtle causes of faulty picture equalization which make changeovers perceptible to the audience in 8 One of the finest equipped, roomiest projection rooms in any institution of learning is that of Ball State College, Muncie, Indiana, where a Strong Xenon projection lamp has just been installed for 16mm film projection along with two Strong Carbon Arc projectors for both V-/J' x 4x/i" slides and 35mm slides. Shown operating the Eastman projector is Robert E. Jolliffe. Two Strong Super Trouper Carbon Arc follow spotlights complete the booth equipment. volve the lateral-guide flanges and the intermittent movements. It is certainly true that if the picture projected by one machine is more or less jumpy, the difference in projectors will be noticed. We can state categorically that, unless the picture has been badly photographed or carelessly printed on the film, or the print is in poor physical condition, there is seldom any excuse for picture-jump or side-weaving. The test for camera or printer jump is simple, although it cannot be carried out during a performance for an audience. The picture must be racked out of frame, with the frameline placed across the middle of the screen. The bottom half of the picture will occupy the top half of the screen, and the top half of the picture, the bottom half of the screen. If these two "picture halves" are seen to weave and jump independently of each other, and the frameline, itself, is rocksteady, the camera used for photographing the picture caused the jump. If, however, the two halves of the picture and the frameline all jump together in the same direction, either the projector is at fault or the sprocket holes of the print are worn out. Address your cards and letters to Sound Track, 1645 Hennepin Ave., Minneapolis, Minn., 55403 After 35 Years George H. Mayer (left) is all smiles as he retires after 35 years with Union Carbide Corporation's Carbon Products Division. For the past decade, Mr. Mayer .has .been .headquartered .in Atlanta, responsible for the sale of arc carbons for motion picture projection throughout .the .southeastern .United States. Extremely active in the Atlanta Men's Garden Club, he was a driving force in the local beautification program that has led to the planting of countless trees and shrubs. Looking on is his wife, Becky, as he receives a retirement gift and good wishes from C. J. Chapman, vice president, marketing, for the Carbon Products Division. Mr. Mayer is also an active member of the Variety Club. International Projectionist June, 1964