Patent GB-364558-A (GB)
Title: Method and means of producing composite photographs with sound accompaniment
IPC: G03C5/14
Filed: 1930-06-27
Abstract: 364,558. Kinematograph picture films ; composite photographs. DUNNING, C. H., 1951, Hillcrest Road, Hollywood, California, U.S.A. June 27, 1930, No. 19609. [Class 98 (ii).] A method of producing in association with a sound record a kinematograph film having composite pictures with separately photographed background and foreground scenes, consists in first preparing a transparency representing a background scene and then printing this on to a film to produce a negative of the background, at the same time as a foreground scene is photographed through the transparency on to the film, simultaneously with the recording of accompanying sound. As an example of the application of the invention, a method of producing a composite picture with sound accompaniment, in which a fortress scene constitutes the background and a balloon basket with its occupants the foreground, is described. A negative photograph of the fortress is first made, and from this a positive is printed on one side of a film having sensitized emulsion on both sides. The positive is then developed and fixed without exposing the other side. Light is passed through the film, to produce a negative on the other side. Next, the positive is dye-toned a colour such as orange, and the negative is dyetoned a neutral shade such as blueish-grey. The dye-toning process consists in bleaching the image, and, after treatment with a mordant and with hypo, replacing the exposed silver salts by dyes of the desired colour. The two dye-toned images are so balanced as to have no differential opacity to white light. The dyed transparency thus obtained is then superposed on an unexposed panchromatic film, and the foreground or action scene is photographed on to the film through the transparency. For this purpose, the foreground is illuminated by light of a colour to which the transparency is uniformly transparent, and a plain background is used, which is illuminated with light that is complementary in colour to the orange or other dye with which the positive of the transparency is toned. In preparing the transparency, the procedure may be changed by starting with a positive of the background scene instead of a negative. A further method of making a double-toned transparency representing the background consists in printing from a negative and positive of the background scene on to sensitized layers on opposite sides of a film, developing and fixing simultaneously, and afterwards dye-toning the two images as described above. Another alternative consists in using a known process in which a print is made on a singlecoated film, the exposed and non-exposed portions of the print being subsequently toned differently, for example blue and grey respectively. If the background scene is stationary, the transparency may be prepared by painting or by photography on glass or the like. The sound may be recorded on the same film as that on which the foreground scene is photographed ; or it may be made synchronously on a separate film, a positive composite picture film with the sound record thereon being finally prepared.