GB283765A - Improvements in and relating to colour photography - Google Patents

Abstract

283,765. Tarbin, W. T. Feb. 1, 1927, [Convention date]. Colour photography.-In the production of colour-record negatives by the simultaneous exposure of a number of superimposed layers sensitized for different colours, the layer sensitive to blue is located during exposure farthest from the source of light, and normally comprises a high speed bromide emulsion. The compound material may include stripping films, and in one form comprises a red-sensitive stripping layer on glass, a blue-sensitive layer on glass, and a green-sensitive non-stripping' layer on thin celluloid enclosed between the layers supported by glass. The stripping films are of known kind, for example such as may be peeled from their supports after cutting round the edges of the film with a penknife. The supports may be held together by clips provided with means, such as V-shaped notches, whir;h form impressions during exposure so as to facilitate registration of the positives subsequently to be printed from the negatives. Certain of the layers may be dyed to act as light filters. When red and green sensitive layers are used which are also sensitive to blue, the formation of blue records on these layers is avoided partly by employing a yellow compensating filter over the taking lens and partly by adjusting the speeds and translucencies of the several layers. For roll-film work or kinematography, the layers may be supported on a single band, as of celluloid, one or more of the layers being strippable; or each layer may be carried on a separate support, and the films be passed together through the gate of the camera, which is provided with means for facilitating registration of the positives subsequently to be printed.