GB387891A - Improvements in four color kinematograph films and in cameras for use therewith - Google Patents

Abstract

387,891. Colour kinematography. THORNTON, J. E., 8, Hill Street, Jersey, Channel Isles. May 26, 1932, No. 14929. Addition to 384,324. [Class 97 (i).] In a process for producing four colour record negatives at a single exposure by means of a light splitting optical system, two superimposed single width films each having two rows of perforations and coated with an emulsion sensitized for a pair of colours, are used in conjunction with two colour filters in alter. nating sequence in front of each film. In the form shown the front film A, Fig. 3, is sensitive to blue and green or orthochromatic, the areas 1 being covered by a pink filter and the areas 2 by a yellow filter. The rear film B is sensitive to red and yellow or panchromatic and the areas 3, 4 are covered by a green and a violet filter respectively. The films are exposed in a camera having a gate G with two openings separated by two picture spaces, the areas 3, 4 being exposed behind the areas 1, 2. A light splitting optical system D, Fig. 5, for example, of the type described in Specification 384,324, is arranged in front of the gate G, a rotating shutter being placed behind the system. The films are fed from a spool S over a continuously running sprocket F, to the gate G and are moved forward by traction pins P which engage perforations in the films. During exposure, the films are held by registration pins P<1>. After passing through the gate the films again pass over the sprocket F and thence to the reel R which is provided with a slipping drive. The pins P are carried on a head H sliding on a pair of pivot bars H<1>, H2 and are moved into engagement with the film by a bell-crank lever h operated by a cam K. The bars H<1>, H<2> are oscillated by a rod k eccentrically mounted on the cam K. In other arrangements the spool and reel may be mounted side by side, or separate spools and reels for each film may be used. Specifications 224,569, 224,570, 224,573, 230,965, 246,266, 285,228, [all in Class 97 (i), Optical systems &c.], 316,338, [Class 98 (ii), Photographic processes &c.], and 384,336 are referred to.