Photographic masks for tonal correction
AssigneeE. I. Du Pont de Nemours and Company
InventorGerhard F. Duesdieker
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Abstract
Process for production of photographic masks for tonal correction by dry dot etching comprising exposing a mask film, e.g., positive film, behind a film combination of half-tone positives and negatives that contains at least one pair of a positive and a negative of the same color separation, said pair being separated from one another by a spacer film, e.g., transparent, matt film, etc. The half-tone values at the points to be corrected are in the range of 30-70%.
Claims6
Process for the production of photographic masks for tonal correction by dry dot etching comprising (A) exposing a silver halide photographic mask film behind a film combination, bound in accurate register, of a half-tone positive and half-tone negative of a color separation set and diffusion sheets, characterized in that the film combination comprises at least one pair of a positive and a negative of the same color separation, whereby the positive and negative are separated from one another by a film taken from the group consisting of spacer film and color separation film, and (B) developing the mask film.
Dependencies are inferred from the claim text.