Exposure control apparatus with compensation for film reciprocity failure
US4264163A · kind A · utility
3Cited by
5References
10Claims
0Family size
Assignee
Inventors
Key dates
| Filing date | Jan 29, 1979 |
| Grant date | Apr 28, 1981 |
| Priority date | — |
| Expiry date | Jan 29, 1999 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG03B7/083
- WIPO fieldOptics
- WIPO sectorInstruments
Abstract
A camera includes a photographic film having a given film speed which decreases when the film is exposed to light which varies from a given illumination level. A camera shutter is controlled by a timing circuit adapted to produce an exposure which is adjusted to compensate for the decreased film speed.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.