The international photographer (Jan-Dec 1936)

Twenty-eight The INTERNATIONAL PHOTOGRAPHER September, 1936 fc^ 'm. Jn Hfomnrtum Since INTERNATIONAL PHOTOGRAPHER for August took its place in the long procession of our magazines, two beloved and well known members of Local 659 have passed "to that mysterious realm where each shall take his chamber in the silent halls of death" — Henry Kohler and Fred Eldredge, friends in life, brothers in their long pilgrimage. Each was a long respected first cameraman of great experience and fine achievement, both in the east and in Hollywood, and popular among their fellows. The line into the sunset grows longer, but to those who mourn these two noble men, there are the consolations of hope and faith and the love of many friends. To these the members of Local 659 and the INTERNATIONAL PHOTOGRAPHER add their heartfelt sympathy. THE DE KAY CONTINUOUS MOVEMENT (Continued from Page 15) culties which have confronted others have been overcome. Perhaps the answer is in its simplicity, for, whereas other patents show complicated mechanism and a number of reflecting surfaces, the De Kay projector (Mr. De Kay has not yet applied his movement to a camera, but has plans for doing so) has a movement which is as simple as most intermittent movements, and has only two surface reflecting mirrors, one of which is stationary and serves merely to change the direction of the light reflected from the oscillating mirror. It is chiefly in the mechanism used to oscillate the mirror that the De Kay movement differs from other continuous movements. Besides its simplicity and minimum wear, it has a micromatic adjustment for changing the oscillation of the mirror so that it can easily be synchronized with the film, and can as easily be adjusted for 16 mm. and 8 mm. film, in which case it is merely necessary to change the sprockets and aperture plate to accommodate the smaller film. The projector is therefore interchangeable for any size film, which would necessitate only one projector for showing industrial and educational films of various sizes. The projected picture is perfectly steady at any magnification, whether new or shrunk film is used, the shrinkage being taken care of by adjustment of the mirror movement. The downward tilting of the oscillating mirror is constant, instead of harmonic as in many continuous movement patents, and the return movement is practically instantaneous, which permits a wider shutter opening. The film aperture is two frames high and frames only the sides of the picture, the horizontal framing being accomplished by a special shutter running close to the film and following the downward move ment of each frame. Because of the steady pull on the film it is necessary to have only a slight pressure on each side of the film. No part of the projector touches the picture portion of the film and the danger of scratching is minimum. The easy, steady pull on the film further prevents breaking and consequently fire hazards. The fireproof cellophane film which recently has been tried in France can be run through this projector any number of times without damage to the film. Since it is only one-third as thick as ordinary positive film, an entire six-reel picture can be put on one 2,000-foot reel, thus cutting down the cost of handling, as well as the cost of the film itself. One of the shortcomings of all present-day projectors is the keystoning of a picture projected on a vertical screen from a point higher than the screen. This can be compensated only by masking the picture to make the sides parallel, but this does not correct the distortion. In the De Kay projector, however, this is overcome by adjusting the mirrors to produce a counteracting keystone. The projector, in addition, creates a pseudo-stereoptic effect. The difference in focus resulting from the changing position of each frame with relation to the oscillating mirror is corrected by shaping the aperture so this type of movement is more quiet, depending, however, on the construction of the movement. Although Mr. De Kay's projector is at present only an experimental model upon which he still intends to make some improvements, a demonstration indicates that it is the furthest advance in continuous movement projection to date and the successful use of the movement in a camera is only a matter of time.