Exhibitors Herald and Moving Picture World (Apr-Jun 1930)

138 Better Theatres Section April 12, 1930 While only clear red, green, blue and white lamps are used, the color and shadow effects which are obtained are unlimited in number. Shades of orange, gray, black, white, yellow, and purple are possible. The result secured depends upon the wattage of the lamp employed for each primary color, and upon the location of the lamp in relation to the flute. There is no set formula to be followed in installing Colorama, as it was pointed out in these columns before. Familiarity that comes from playing with light and color, and observing the infinite varieties of effects obtainable, is the key to its use. It is amazingly simple, depending for its gorgeous effects upon lavish, unstinted use of a large number of simple elements. A few sheets of cardboard, a few color hoods, and a few lamps on flashers or dimmers, is perhaps about the best instruction one can take in this form of decoration, which, I believe, is bound to grow very rapidly. New Film Cement • An interesting development among accessories is a new non-inflammable film cement, brought out by Edward H. Harris, who worked with William Fox when Fox had but six films under the unblushing title of The Greater New York Film Rental Company. Since 1914 Harris has been actively engaged in the production and marketing of film cement. Until a year ago he offered a cement capable of welding both the standard inflammable film of 35-mm. width, and the amateur non-inflammable 16-mm. width. This cement, however, is flammable. He now reports the creation of a substance that combines the features of his original product, that of being able to weld both classes of negative, and yet, is non-inflammable. The product is called “Flame Proof 2-in-l Film Cement,” and is distributed by the Hewes-Gotham Company. Just what the secret in his product is, Harris could hardly be expected to divulge, but the principle is the substitution of the two inflammable ingredients in ordinary film cement, collodion and amylacetate, or banana oil, with other substances having the same properties but being non-inflammable. Besides the important element of safety, this product, by eliminating collodion, is said to do away with the “gumming up” and thickening of the patch. Also, its volatility being lower than ordinary cement, it probably would not evaporate as quickly. And, by the way, Harris says that application of the same principle to the making of fireproof screens may result in an absolutely unburnable screen. Blower Improved • Completion of improvements in the Sirocco blower, manufactured by the American Blower Corporation and distributed by the National Theatre Supply Company, are now reported. The air capacity of this fan has been increased so that even though running at low speeds, it provides the same amount of ventilation as it did formerly at high speed. The change was made in the special interest of the quietness now required of ventilation systems in theatres showing sound pictures. The changes include mechanical features designed to eliminate hum and vibration. Also prominent among the new things in National Theatre Supply Company equipment, is a series of lobby frames and lobby display cases. The line of the Menger, Ring & Weinstein company, distributed by National, has been augmented by frames and cases designed to compare with the finest of these articles, yet to sell at popular prices. Practically any style and size can now be obtained in this new service. Heat-on-Film Today • Considerable data has already been published in this publication as well as elsewhere, on the effect of the rear shutter on the heat from the light source on the film. There is no question, of course, that the heat is far less with the rear fan-like shutter, than with the front wheel-like shutter. But how much less? This is being gone into again because the controversy has been brought to the attention of this desk by one of the leading projector manufacturers, which firm has been getting a lot of inquiries on the subject. I leave it to my colleague, Mr. F. H. Richardson, to consider such matters from the point of view of the projectionist. My remarks on the subject are confined to a report of new data offered by the Enterprise Optical Company, makers of the Motiograph projector, the first machine, as everyone knows, to have had the new-type shutter. Primarily, the Motiograph shutter was designed for the important function of eliminating the heat from the film. This heat on the film was fast becoming a serious problem. Constant demands for more light on the screen brought out more powerful illuminants, including high intensity, reflecting arc, and high intensity-reflecting arcs, each adding more heat on the film, along with the in crease in light. With the increased heat on the film came the attendant difficulties of warped and buckled film, which caused still further difficulties in connection with the reproduction of sound from the film. The rear shutter on the latest Motiograph mechanism is different from all other types of rear shutters. Its design represents a long series of experiments with rear shutters of every type in an endeavor to obtain a type which would attain three purposes: To eliminate most efficiently the greatest possible amount of heat from the film, to provide a means of cooling the metal parts of the projector adjacent to the film aperture, and to provide, if possible, an increase in screen illumination. The result of this effort was the horizontal cylindrical shutter pictured in Figure 1. The shutter is positioned between the light source and film, being mounted in a cast aluminum housing and rotating on ball bearings. Its action in intercepting the light beam, and incidentally the heat, was found by test to eliminate 62y2 per cent of the heat from the film. First, tests were conducted to determine the amount of heat on the film with a mechanism using the old type of front shutter. Then, with the same illuminant operated at exactly the same amperage, the test was conducted with the new mechanism with the horizontal cylindrical shutter. It is interesting to note that a small variation in heat on the film was recorded at different speeds with the horizontal shutter positioned between the light source and film, whereas the heat on the film with the old type of front shutter was constant at all speeds. The result of the tests showed heat on the film with the old type shutter at 1,486 degrees, whereas the average taken of the different readings at different speeds showed that the horizontal shutter reduced the heat on the film to 922 degrees less, or 564 degrees, as against 1,486 degress, or a percentage of 62%. This elimination of the heat from the film is due to the action of the two vanes or blades of the horizontal shutter, which are so arranged that the light beam is Fig. 1