PROCESS FOR THE PRODUCTION OF HALF-TONES COPIES OF A STANDARDIZED DENSITY

1,262,305. Photographic printing processes. AGFA GEVAERT A. G. Jan. 17, 1969 [Jan. 20, 1968], No.44342/71. Divided out of 1, 262, 304. Headings G2C and G2M. The process of the Specification 1, 262, 304 is modified to produce half tone copies of continuous tone originals by a silver halide emulsion layer with a steep gamma-value greater than 4À0 in combination with a coloured contact screen so that a first gamma is obtained with light of colour L 1 and a second gamma is obtained with light of colour L 2 and adjusting the exposure to L 1 , L 2 so that the resulting characteristic curves intersect at a particular density value which corresponds to the desired density value to be obtained in the shadow portions of the positive copy. A magenta coloured contact screen is preferably used.