Motion Picture News (Sept-Oct 1916)

1918 ACCESSORY NEWS SECTION Vol. 14. No. 12 Just one clear picttire after another with Eastman Film The film that made motion pictures practical plays a big part in their present stage of perfection. Look for the stencil mark "Eastman" in the margin. EASTMAN KODAK COMPANY, ROCHESTER, N. Y. INFORMATION I am interested in Motion Picture Photography and would like Without Obligation on my part to obtain information on the equipment as checked CAMERAS CAMERA ATTACHMENTS TRIPODS LENSES FILM STOCK STUDIO LIGHTS LABORATORY APPARATUS DEVELOPING AND PRINTING (Tear out this advertisement and mail to MOTION PICTURE NEWS, 729 7th Avenue, New York.) Name Theatre Address gratings. Rowland, that master maker of diffraction gratings, produced another type of reflection grating — the concave grating. The concave grating is one on which the hnes are ruled upon a curved mirror of speculum metal and is, in many respects, the most remarkable and efficient of all types of gratings, it being possible to resolve, with the concave grating, lines which are not seen separated, in the spectra produced by any other device. We are afraid that many amateur readers, perhaps, do not like to see the Camera Department given over to matters of such a deep technical nature as those at present under consideration. We assure all readers of the Camera Department, however, that we will, in the course of another issue or two, have all of tliese preliminary considerations disposed of, and we will then be able to proceed with a graphic description and discussion of the various processes by which photographs and motion pictures in natural colors are produced. It is hoped, on the other hand, that the scientific considerations at present occupying the department will find favor with our readers, because, there is an astonishing lack of scientific knowledge displayed by the majority of cameramen. The cameraman of the future will have to be something more than an empirical muddler and instead of writing about the larger salaries which cameramen should receive, we propose to lay the groundwork of the knowledge which cinematographers must possess in order to secure the larger salaries. This, the policy of the Camera Department, will obtain in the future as it has in the past. (.To be continued next ueek.) CLEANING FILM POSITIVES 0. F. F. C. of Albany, N. Y., inquires: " Kindly let us know the best way of keeping film to prevent dryness and also as to cleaning them. Would appreciate this information very much as we are troubled somewhat by both of the above." In reply : This inquiry, while not quite within the province of the Camera Department has come the way of the editor, so we will advise to the best of our ability and recollection. We presume that the correspondent (whom it appears operates a film exchange) is already provided with film vaults or metal film safes. There is a compartment at the bottom of these film safes where pans (or other containers) filled with water may be placed, to keep the reels of film in a moistened condition. Some place a large sponge saturated with water in the lower part of their film containers. A number of years ago, when all matters pertaining to the technical end of film manufacture received more attention than they now do, most all laboratories used to immerse the films in a weak solution of glycerine in water just prior to drying. Glycerine has an affinity for water, and a film treated with glycerine tends to aborb sufficient moisture from the atmosphere to cause it to remain pliable for an extended period. The omission of the ghxerine treatment by most laboratories at present, however, is responsible for the rapidity with which a film dries out and becomes brittle. There is a way of remedying this deficiency to some extent. While visiting that sterling projection expert Cecil R. Woods, at the Liberty theatre, N. Y., during the early days of the " Birth of a Nation's " presentation there ; we saw, among many other interesting things, the use of glycerine and moth balls (camphor) as a film preservative. In the lower part of the film cabinet, at the " Liberty," was a pan containing a quantity of glycerine, into which had been thrown a dozen or more moth balls. As camphor, which is more or less volatile, is a constituent of the celluloid film base, it was made possible in this way to restore to the film the camphor and the moisture which it was deprived of when projected. As the original print of the "Birth of a Nation" lasted a long while, we believe this treatment must have been very efficient. With regard to the cleaning of film^ — this is a little more like work. Although our opinion is, perhaps, not final, we do not look with favor upon the devices which attach to the rewind table and through which the film is run. Our reason is — that when using such a device the dirt and grit removed (by the pads) from the first section of film run through, serves to scratcli the remaining portion of the film in its passage through the device. Of the various renovating machines and systems some "deliver" while some do not seem to benefit the films thus processed. The Be sure to mention " MOTION PICTURE NEWS " when writing to advertisers