The motion picture projectionist (Nov 1931-Jan 1933)

December, 1931 Motion Picture Projectionist 25 Mr. Falge: To a certain extent; but the solvents that have been tried have loosened the adhesion of the beads and so such methods have not been found satisfactory up to the present. President Crabtree: The matter of standardizing screen sizes is very important. Has this matter been brought to the attention of the Projection Screens Committee? Mr. Falge: Yes, but nothing definite has been done about it as yet. Mr. Schlanger: The information given in this paper referring to the proper distance between the seats and the screen is very important and should be referred to the American Institute of Architects. In relation to the shape of the screen, I suggest that perhaps Mr. Dieterich might say something about the restful physiological effect of the 3 to 5 ratio on the human eye. Three to Five Ratio Mr. Dieterich: Yesterday I briefly mentioned the fact that there is a minimum distance required between the eyes and the screen for comfortably viewing the picture. To go a little deeper into the discussion we must consider the sight characteristics of the eyes, which when plotted assume a peculiar egg-shaped form for each eye. The combination of the two characteristics produces a more or less heart-shaped curve for the combined characteristics of the two eyes — i.e., for binocular vision. If we inscribe a rectangle into the combined characteristics we are led to the classical ratio of height to width of 1 to 1.6. As long as we have to change the proportions of the visible picture — which we must do sooner or later — ■ we should consider the esthetic demands, because they control to a great extent the reaction of the public, which again influences box-office returns. As long as it is necessary to change the dimensions, I am endeavoring to advocate that we should change in accordance with this ratio. There will be a number of technical difficulties, and problems to overcome, but they will have to be overcome sooner or later, in any event. Committee's Suggestion The Standards Committee has suggested a 50-mm. width for production reasons, but we can just as well use the proper proportions for this width as for any other. Mr. Schlanger suggested that when one sits in front of a screen that is 40 feet wide he may come closer than 40 feet. However, this would not place the screen within the "easy" range of the eye. The eye must exert an effort to encompass an angle greater than 60 degrees and although our total vision is limited only by about 180 degrees, it becomes a painful effort to use it to its full extent. Along the horizontal axis of vision, the "easy" range is normally 30 degrees on each side, and along the vertical axis about 10 degrees above and 20 degrees below the horizontal. If the scheme of Mr. Schlanger is in accordance with these physiological facts, he will find that the spectator will enjoy the picture more than in the past. As to the question of depth perception, the recognition of depth in the wide picture is due to the fact that when one looks at a wide screen, the distances to the edges of the picture are perceptibly greater than the distance to the center, and the eye has to accommodate itself to such different focal values. Therefore, the only means of perception, which is by the final nerve center, would cause a reaction, resulting in a muscular effort to accommodate the eye. Therefore, the wide picture has certain disagreeable effects for the present front seats, but which lessen as the distance from the screen increases. The minimum distance between the screen and the front seats should not be less than the width of the picture. Mr. Falge: The ratio you suggested is close to the 3 to 5 ratio which I mentioned previously. Effect of Surroundings MR. Jones: There was one statement in Mr. Falge's paper I should like to question. In discussing the diffusing type of screen he stated that the brilliance of the screen depends upon the viewing distance. I cannot see why the argument applies to the diffuse type of screen and not to the beaded type. It is quite possible that the brilliance of the screen — that is, the apparent brightness — is to a certain extent influenced by the angle of the screen and by the surroundings. I think it is quite possible — and I know it is true — that whether the screen appears to be more brilliant at one distance that at another will depend upon the surroundings of the screen. I think we should recognize that that characteristic, which may be a true phenomenon, is a characteristic of all types of screens, and I cannot see that it is a characteristic of a diffuse type of screen any more than of any other. Mr. Falge: What I meant to convey was that this effect is more pronounced in the case of the beaded screen. I referred to it briefly in connection with the beaded screen. As far as the surroundings are concerned, if too much light is present, the pupils of the eyes become smaller and the screen does not appear as brilliant as one would like it to be. Mr. Otis: Have any measurements been made on the diffusiveness of the screens to color? Mr. Falge: Do you refer to a particular one of the three types, or to all screens? I do not believe that such measurements have been made. Mr. Schlanger: Referring to the shape of the picture and the desir ability of retaining the 3 to 5 ratio, it is possible to change the shape of the screen throughout a picture so as to present different geometrical forms — triangular, rectangular, circular, etc. I understand that some work has already been done along that line. Mr. Dieterich: Madame Ducat, the only female member of the Legion of Honor, has invented a new "panel" aperture. Her idea is that everyone who has a sense of the artistic frames a picture or composition according to the composition, and does not take the frame and fill it with the composition. The frame should be under the control of the cameraman so that he may instantaneously alter the picture frame as desired. This does not depart from, the 1 to 1.6 ratio for the shape because this ratio is an esthetieally fundamental one from which any number of frame sizes can be developed. Her idea of changing the frame size according to the action has been successfully used because she understands the correct use of the panel frame. A Progressive Police Dept. For the purpose of demonstrating the possibilities of sound motion pictures in recording confessions and other evidence of importance in police department activities and upon the invitation of Police Commissioner Eugene C. Hultman of Boston, an experiment was conducted in the hearing room of police headquarters in that city through the medium of RCA Photophone portable recording equipment. With a cast of characters composed of the Boston police force, members of the bureau of criminal investigation and representatives of the press, a scene depicting the methods customarily pursued immediately following the arrest of a person alleged to have committed a crime was recorded and photographed. Several days later the scene was reproduced by RCA Photophone portable sound reproducing equipment for those who had been present at the recording operations. Paul Robillard of the engineering department handled the recording operations under the direction of Grover C. Schaefer. H. L. Whitney, district manager of the Installation and Service Department, arranged for the demonstration. Hall & Connolly Develop New Arc Lamp Announcement has been made by Hall & Connolly of a new and radically different high intensity projection lamp for current ratings of from 75 to 200 amperes. It is said that the new unit contains a number of striking improvements which will result in better projection and greater ease of operation.