The motion picture projectionist (Nov 1931-Jan 1933)

August, 1932 Motion Picture Projectionist 31 "master negatives." From each of these two master negatives a printing matrix is made by printing the same upon a strip of film which is then developed and subjected to a certain chemical treatment which raises and hardens the silver deposit in a fashion which closely resembles a photo-engraver's printing plate. With these two matrixes ready, a blank strip of celluloid is covered with a layer of gelatine which is color absorbent. Then the matrix containing the red impressions is dipped into a red dye solution and applied like a printing plate to this blank strip of gelatine covered celluloid. During this operation of transferring the red dye from the printing matrix to the gelatine layer, both the matrix and the gelatine coated strip of celluloid must be held together very rigidly by a mechanical contrivance to prevent "blurring" of the image. After the red parts of the image are impressed or "imbibed" on the gelatine coated celluloid, the same process is repeated with the matrix containing the bluish;green impressions of the scene photographed. This matrix is soaked with a bluish-green dye solution and imbibed on the gelatine layer directly over the color which has already been imbibed from the red image. The gelatine layer is now interpenetrated with both dyes — red and bluish-green — in exactly the same proportions that those colors with their varying shades existed in the scenes photographed originally. While this lithographing process may not be simpler, less expensive or more fool-proof in its operation than the other types of the subtractive method, it does permit greater transparency of the finished product and •does away with the many shortcomings of the double coated positive stock besides being less affected by scratches of the projector. Which of my readers has not asked himself about the red and green "rain" that appeared on a double coated film after several projections? A scratch on a black and white film, on a Wolff-Heide Film or on a Technicolor lithographic process leaves the scratched surface blank, while on double coated films the scratch removes the color from the scratched surface en one side but not on the other side and the result is a red and green colored "rain." Experts on both sides of the Atlantic frankly admit that none of the existing "additive" or "subtractive" processes is a satisfactory solution to the problem of moC.on pictures in color. In fact, we may as well admit, that the existing processes are far too complicated and expensive to permit their adoption under the present financial condition of the producers of motion pictures, nor can we shut our eyes to the fact, that the quality of the majority of color productions released so far was not such as to find enthusiastic reception among the audience. The only features in color thffmdnn-Soom PERPPcnON I V — — %V>— i ^yz T is no exaggeration to say that our rheostat is internationally famous. Four out of every five theatres in this country use Hoffmann-Soons Rheostats exclusivdy. A first class product, backed by reputation and guarantee. It always leads the field. Now equipped with solderless, adjustable lugs ta take wire sizes from No. 4 to No. 4/0 without any additional cost. V THE ONLY UNION MADE RHEOSTAT HOFFMANN-SOONS Electrical and Eng-ineeringr Corporation 387 First Avenue New York City Manufacturing Division Contracting Electrical Engineers Moving Picture Electrical Specialists SUN-ARC CARBONS for PERFECT PROJECTION "BEST BY TEST" Big Savings — Complete Satisfaction Casco Carbon Saver for Hi-Low and Hi-Intensity carbons, FREE OF CHARGE. Permits the burning of carbons down to 2 in. and less. Carbons furnished ready for use. 'So inconvenience whatsoever for the operator. Samples on request. Address CARBON PRODUCTS, INC. 324 West 42nd Street New York City