Photocopying – Projection printing and copying cameras – Illumination systems or details
Patent
1981-11-12
1983-04-12
Miller, C. D.
Photocopying
Projection printing and copying cameras
Illumination systems or details
355 77, 355 41, 356444, 250559, G03B 2780
Patent
active
043796320
ABSTRACT:
Successive frames of spliced-together exposed and developed photographic films are examined prior to introduction into a copying machine to prevent the reproduction of film frames having blurred images. Portions of or entire film frames at an examining station are spot scanned, line-by-line, and the resulting video signals are processed to determine one or more quotients which denote the ratio of maximum density gradient to density range of the respective film frames, the ratio of first and second density gradients obtained on scanning the entire frequency spectrum or the lower density portion of a film frame, and the ratio of frequency of occurrence of the first and second density gradients. Such quotient or quotients are compared with a threshold value and the results of comparison are used to classify the film frames as suitable or unfit for the making of reproductions.
REFERENCES:
patent: 3455632 (1969-07-01), Neale et al.
patent: 3981579 (1976-09-01), Weinert et al.
patent: 3984184 (1976-10-01), Pflugbeil
patent: 4099064 (1978-07-01), Grossman
patent: 4239384 (1980-12-01), Treiber
patent: 4251157 (1981-02-01), Knor et al.
Dedden Hubert
Pfingst Jurgen
Agfa-Gevaert Aktiengesellschaft
Brady W. J.
Miller C. D.
LandOfFree
Method and apparatus for previewing exposed photographic films o 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 and apparatus for previewing exposed photographic films o, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Method and apparatus for previewing exposed photographic films o will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-937620