International projectionist (Jan-Dec 1938)

and operated by divers. The rest of the paper deals with the problems of and equipment for such work. It is pointed out that studio tank work shares most of these problems. The optical properties of water are described. Since water is less transparent than air, photography by natural light is limited to small depths and more power is required for artificial illumination under water. Since colors are not absorbed equally, accurate monochrome rendering and photography in natural color are complicated. Water haze limits the distance at which pictures can be taken under water. This haze is largely confined to a part of the spectrum and can be eliminated partially by color-filters. It is polarized and can therefore be eliminated also by polarizing plates. The advantages of this method are briefly stated: they do not distort the monochrome rendering, and may be used in natural-color photography. The ideal attributes of equip ment for use in underwater cinematography are outlined and available equipment is briefly described. IMPROVING THE FIDELITY OF DISK RECORDS FOR DIRECT PLAYBACK H. J. Hasbrouck, Jr. RCA Manufacturing Co., Inc. Recent advances in equipment design and in materials of which recording disks ars composed, have resulted in improved fidelity. Both the volume range and the frequency range have been extended, satisfying presentday requirements of motion picture and broadcast applications. For reproduction, there is provided a new lighter weight lateral pick-up having high sensitivity and equipped with a permanent diamond point. This reproducer, in combination with its associated circuit, is suitable for use on all laterial-cut disk records. Pre and post-equalization are employed in the method described for making highfidelity records, insuring an extremely low noise-level. This absence of background noise together with the wide frequency range and low overall distortion create an illusion of reality or "presence" during reproduction. Usually a great many of playings are not required of direct playback disks. However, because of the low mechanical impedance of the new RCA pick-up and the improved composition of the disks it is possible to reproduce 75 to 100 times without appreciable increase in noise or distortion. Great differences in record life under various conditions of handling have been noted and are attributed chiefly to accumulation of fingerprints and dust on the record surface. Gradual oxidation of the lacquer coating must also be considered and guarded against by special care when records of this type are intended for long preservation. REPORT OF THE STUDIO LIGHTING COMMITTEE C. W. Handley, Chairman In a previous report the need of a catalogue of studio lighting equipment was emphasized. A number of papers have been published which describe various lamps and light sources in detail, but there has not been assembled in one paper a symposium of all types of equipment and light sources. It is the intention of the Committee to correlate the published and unpublished data on motion picture studio light sources in such a form as to make this report a refer ence for complete information on the subject. The various lighting units are numbered and briefly described. Photographs of popular lamps are shown. Tables give minimum and maximum beam divergences, carbon and bulb sizes. Journal reference numbers are given as a key to further specific information on any lamp or illuminant. Data on light control devices and lamp filters is included. LATEST DEVELOPMENTS IN VARIABLE AREA PROCESSING A. C. Blaney and G. M. Best The purpose of this paper is to present a scries of curves showing the photographic control of variable area sound tracks as obtained in commercial production at Warner Bros. Studio, and to show the wide tolerances in film processing which are permissible with Class-A push-pull recording, a factor which is of especial interest in connection with the daily production. The results of a study of the technique involved in fine grain photographic duplicating of variable area sound track, for foreign release is also discussed. THE M. G. M. SEMI-AUTOMATIC FOLLOW-FOCUS DEVICE John Arnold During recent years an important problem in major-studio cinematography has been that of following focus. Due to the shallow depth of field in modern lenses when used at maximum apertures, it is necessary to alter the focus frequently during the filming of a scene, to keep the actors properly fo Fit Every Type of 'heatre Whether your auditorium is square, rectangular, oval or circular, there is a Da-Lite Screen with the RIGHT surface to give you perfect projection. Write for details or see your dealer. DA-LITE SCREEN COMPANY, Inc. Z715 N. Crawford Ave., Chicago, 111. cused. In moving-camera shots, which are being used with increasing frequency, this problem is naturally aggravated, since both camera and players may move. The use of "blimped" cameras for sound pictures also aggravates the cameramen's problems, as finder parallax is greatly increased by placing the finder outside the camera "bungalow." At the Metro-Goldwyn-Mayer Studio these problems have been simplified by the use of the Semi-Automatic Follow-Focus Device. This consists of a finder which is both focused and pivoted to correct for parallax as the lens is focused. Individual cams coordinate the finder movement with the characteristics of any given lens. So successful is this coordination that it is possible to determine whether or not an object is correctly focused in the camera by observing the object's focus and position in the finder. The device has been applied to all cameras used in production at the Metro-Goldwyn-Mayer Studio, and has over a period of several years proven to be accurate, dependable, and has facilitated production to a noteworthy degree. STATEMENT OF THE OWNERSHIP, MAN AGEMENT, CIRCULATION, ETC., REQUIRED BY THE ACTS OF CONGRESS OF AUGUST 24, 1912, AND MARCH 3, 1933, Of International Projectionist, published monthly at New York, N. Y., for October 1, 1937. County of New York 1 State of New York f Before me, a Notary Public in and for the State and county aforesaid, personally appeared James J. Finn, who, having been duly sworn according to law, deposes and says that he is the Editor of International Projectionist and that the following is, to the best of his knowledge and belief, a true statement of the ownership, management (and if a daily paper, the circulai hi), etc. of the aforesaid publication for the date shown in the above caption, required by the Act of August 24, 1912, as amended by the Act jf March 3, 1933, embodied in section 537, Postal Laws and Regulations, printed on the reverse of this form, to wit: 1. That the names and addresses of the publisher, editor, managing editor, and business managers are: Publisher, James J. Finn Publishing Corp., 580 Fifth Avenue, New York, N. Y. Editor, lames J. Finn, 580 Fifth Avenue, New York, N. Y. Managing Editor, None. Business Manager, Ruth Entracht, 580 Fifth Avenue, New York, N. Y. 2. That the owner is: James J. Finn Publishing Corp., 580 Fifth Avenue, New York, N. Y. James J. Finn, 580 Fifth Avenue, New York, M. Y. Ruth Entracht, 580 Fifth Avenue, New York, N. Y. 3. That the known bondholders, mortgagees, and other security holders owning or holding 1 per cent or more of total amount of bonds, mortgages, or other securities are: None. 4. That the two paragraphs next above, giving 'he names of the owners, stockholders, and security holders, if any, contain not only the list of stockholders and security holders as they appear upon the books of the company but also, in cases where the stockholder or security holder appears upon the books of the company as trustee or in any other fiduciary relation, the name of the person or corporation for whom such trustee is acting, is given; also that the said two paragraphs contain statements embracing affiant's full knowledge and belief as to the circumstances and conditions under which stockholders and security holders who do not appear upon the books of the company as trustees, hold stock and securities in a capacity jther than that of a bona fide owner; and this affiant has no reason to believe that any other person, association, or corporation has any interest direct or indirect in the said stock, bonds, or other securities than as so stated by him. James J. Finn, Editor Sworn to and subscribed before me this 6th day of October, 1938. (Seal) ALAN R. MOHLER Notary Public, New York County Clerk's No. 550. (My commission expires March 30, 1940.) 30 INTERNATIONAL PROJECTIONIST