The motion picture projectionist (Oct 1927-Sept 1928)

July, 1928 The Motion Picture Projectionist 15 Fig. 2— Close-up of cone, shutter and mechanism was taken from the film can. Moreover, the film will be absolutely flat, unwarped, buckled or embossed. Its third purpose bears directly on the foregoing and benefits the entire industry in that because of eliminating the heat the film has longer life, it reaches the theatre in better condition, it eliminates dried out patches which result in stops, create fire hazards and annoy theatre patrons. Aside from abolishing these annoyances, however, it directly improves projection and enhances the definition of the picture. The film being flat and unwarped and relieved of the intense heat at the aperture, there is no tendency for the film to buckle. As a consequence, the projection lens is able to function to deliver to the screen a true projected image from a flat focal plane. So important is this point that all the advantages of the high corrections of the really excellent modern lenses are fully realized. All of the fine detail and gradations of the present excellent examples of photography are transmitted to the screen in a beautifully defined and sharply focused image. This cannot be accomplished where the intense heat of the light beam is allowed to reach the film since under that condition the film buckles and absolutely true focus is impossible. Many Hazards Eliminated In the fourth purpose, we find that the new type shutter serves to reduce the fire hazard at least 60%. First, because of the fact that the heat being removed from the film almost entirely, combustion would be retarded. Second, being positioned between the film and light source and having two vanes or blades, there is a fifty-fifty chance that the vanes of the shutter would act as a fire shutter in the event that the mechanism or film should stop motion. Then there is the entire elimination of fire hazard due to the drying out of patches and the dried condition of the film itself. The fifth purpose is also distinctly worthy and important. By a peculiar and carefully worked out design of the shutter construction wherein its ends are angled similar to the blades of a fan, but c.r ' of different pitch, and by the addition of air dissembling vanes there is produced a circulation of air which draws the radiated heat away from the film tracks, tension shoes and springs, gate slide and cooling plates so effectively that these important parts are always cool and in a condition to function perfectly at all times. The shutter and its housing are constructed of cast aluminum. Its bearings are of the ball bearing type, and due to the absence of friction, the entire mechanism operates more freely. There is an estimated 25% less pull on the motor,.. Advantages for Projectionist 4; i A novel method of manually setting the shutter in time has been worked out so that this operation when necessary may be speedily and simply accomplished and in a way that does not in the least affect the ready removal of the intermittent movement. A locking device and a shutter setting knob conveniently located on the operating side of the projector is provided for securing fine limit timing of the shutter while the mechanism is operating. In fact, all the advantages of the old outside front rotating shutter have been retained with none of its disadvantages. The complete enclosure of the new shutter and its Fig. 3 — Gears of old type construction Fig. 4 — Gears of new type construction