Method for colour correction by dry dot etching using photograph

Details Method for colour correction by dry dot etching using photograph Method for colour correction by dry dot etching using photograph

1989-06-29

1991-04-23

Britton, Howard W.

Facsimile and static presentation processing

Static presentation processing

Attribute control

358 76, 358459, 355 20, 355 68, 355 77, 430 44, 430 22, G03F 308, G03F 310

Patent

active

050103989

ABSTRACT:
A method for dot-size correction or modification in half-tone colour separations to be used in the production of printing plates for printing reproductions of coloured originals in which a contact print is overexposed through a photographic mask constituted so as to isolate a selected area in addition to being exposed normally for obtaining an exact copy of an original half-tone separation. The mask is generated electronically using an electrical signal obtained by scanning each separation, digitizing each signal and storing the digital values in a digital storage device. A halftone separation is visualized electronically as an image in a dislay device, e.g., video tube, an area of said image is defined for isolation and correction and the combination of positive and/or negative separations required to serve as a mask effective for isolating the selected area for purposes of dot evaluation is determined via a look-up table. The mask is visualized on the display device, evaluated for correctness, the isolation area is re-defined visually, and a new combination of separations to effectively mask the re-defined area is determined and evaluated. The resultant mask is reproduced photographically and used to identify the needed degree of dot correction. It is then also used to generate a dot-corrected photographic print by subjecting print material for said print to two photographic exposures, one being the normal exposure to reproduce the corresponding halftone separation and the other being an overexposure through the combination of the photographic mask and the corresponding separation for a dose to give the needed change in dot size.

REFERENCES:
patent: 4305094 (1981-12-01), Yamada
patent: 4393399 (1983-07-01), Gast et al.
patent: 4396940 (1983-08-01), Tanaka et al.
patent: 4414636 (1983-11-01), Ueda et al.
patent: 4430668 (1984-02-01), Mices, Jr.
patent: 4463373 (1984-07-01), Mikami
patent: 4602294 (1986-07-01), Yamada
patent: 4692796 (1987-09-01), Yamada et al.
patent: 4708459 (1987-11-01), Cowan et al.
patent: 4717954 (1988-01-01), Fujita et al.
patent: 4782384 (1988-11-01), Tucher et al.
patent: 4802107 (1989-01-01), Yamamoto et al.

Affiliated with

Also associated with

Rating

Method for colour correction by dry dot etching using photograph does not yet have a rating. At this time, there are no reviews or comments for this patent.

If you have personal experience with Method for colour correction by dry dot etching using photograph, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Method for colour correction by dry dot etching using photograph will most certainly appreciate the feedback.

Rate now

Comments { 0 }

Profile ID: LFUS-PAI-O-1624707