GB811311A - Process for improving the colour reproduction in the reproduction of multi-colour images - Google Patents

Abstract

811,311. Colour photography. AGFA, A. G. Aug. 19, 1955 [Aug. 20, 1954], No. 23989/55. Drawings to Specification. Class 98(2) Colour corrected separation records or multicolour images are made by a negative-positive process from a multicolour image by exposing the latter on to at least two light-sensitive layers each sensitive to a different two-thirds of the spectrum, processing as by colour development to produce coloured masking images the dyes of which have their main transparency in the regions of the spectrum to which each masking layer is sensitive and thereafter printing the multicolour image through the masks to make the corrected records or multicolour images. The masking layers may be on separate supports and one or several of them may be sensitized to the whole region of the spectrum, the recording power of such being, however, restricted by the use of an appropriate subtractive filter as of yellow, magenta or cyan or by a pair of additive filters; but Figures (not shown) illustrate a single film for the purpose which has in order support, layers (1) green and red sensitive for processing to yellow, decolourizable yellow filter (2) blue and green sensitive for processing to cyan and (3) blue and red sensitive for processing to magenta, and each layer of this combination is operative in making a colour separation record corresponding to its colour. Layer (2) however is usually superfluous and the masking film can be reduced to layers (1) and (3), or layer (2) can be replaced by a red-sensitive layer for equalizing gradation, such must however be disposed together with layer (1) beneath the yellow filter. A further Figure shows the masking film arrangements for false colour procedure. The masking images may be combined with black and white tone-correcting or contrast-reducing masks.