GB433542A - An improved system of natural-colour kinematography - Google Patents

Abstract

433,542. Colour kinematography. CRICKS, R. H., 159, Wardour Street, London, and GREENE, C. FRIESE-, 23, Normandy Avenue, Barnet, Hertfordshire. Feb. 14, 1934, No. 4852. [Classes 97 (i) and 98 (ii)] The colour-record picture frames produced by simultaneously exposing two negative films running at half the desired projection speed, and the frames produced by printing such frames in alternation on a positive film, occupy substantially the whole film area normally reserved for pictures. The negative films may be exposed as a bi-pack, or by means of a beam-splitting prism and gates at right-angles. In a bi-pack, the film nearer the lens may have an orthochromatic emulsion on the side further from the lens, the emulsions being covered with a filter stratum for a panchromatic emulsion in contact with it and carried by the rear film; the redsensitive negative is thus produced further from the lens than the other, and compensation for the longer focus of the lens at the red end of the spectrum is effected. Compensation for difference in size of the images is effected by adjustment during printing or by control of the shrinkage of the negatives during processing. The positive film may be projected through separate filters or may carry filters sprayed thereon ; dyes described in Specification 233,129, [Class 97 (i)], may be used. The colour bands of the filters, both in taking and projecting, may overlap to reduce colour pulsation and to secure lighter tints in the projected picture. The images may be projected successively by means of a shutter making one revolution for two frames and having unequally spaced apertures. The shutter may, alternatively, make one revolution for each frame, and may have a normal cover blade E, a narrower opaque flicker blade F, a narrow red sector R on one side of the blade F, and a narrow green sector G on the other side of the blade F.