A PROCESS FOR THE PRODUCTION OF NEGATIVE OR POSITIVE CONTINUOUS TONE OR SCREENED IMAGES THEREOF

1277213 Photographic processes AGFAGEVAERT A G 8 July 1969 [8 July 1968] 34384/69 Heading G2C Negative continuous-tone images or negative colour separation records are produced in a camera or by contact from a plurality of positive opaque or transparent black-and-white or coloured originals with different density ranges by an exposure for a time sufficient to provide an exposed film having a predetermined density for the highlight areas of the original, which predetermined density is identical for each negative, and subjecting each negative after exposure to identical development. The copying material preferably comprises at least one silver halide emulsion layer the gamma of which varies with the colour of the copying light, the sensitivity being adjusted so that equal exposures to light of a colour L 1 and to light of a colour L 2 produce the required density of the highlight areas of the original. The negatives may be subsequently used as originals to produce continuous-tone positives by use of the same type of emulsion layer or to produce halftone positive by use of a copying film having a high gamma of at least 5 with a coloured contact screen.