Digital process sensitivity correction
US5667944A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Apr 22, 1996 |
| Grant date | Sep 16, 1997 |
| Priority date | — |
| Expiry date | Apr 22, 2016 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG03B2217/243
- WIPO fieldOptics
- WIPO sectorInstruments
Abstract
A method for producing photographic images from a photographic film strip, of the type that uses density values of the photographic film strip to determine the density values of the produced photographic images, the improvement comprising the steps of: PA1 a) forming at least two reference patches of differing exposure conditions onto an otherwise unexposed portion of the photographic film strip prior to photographic processing, each reference patch falling within the total scale of the photographic film strip; PA1 b) photographically processing the photographic film strip to form densities corresponding to the photographic images and said reference patches; PA1 c) scanning said processed photographic film strip to form density representative digital signals for the photographic images and said reference patches; PA1 d) obtaining standard film density values representative of the photographic film strip; PA1 e) calculating gamma correction values from said density representative digital signals corresponding to said reference patches and said standard film density values; PA1 f) utilizing said calculated gamma correction values and said density representative digital signals corres…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.