US2737457A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Photographic method of tonal scale compensation
Assignee: Individual
•
Filing: 1952-11-22
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Granted: 1956-03-06
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Expires: 1972-11-22
Abstract
No abstract record available.
Inventors
- 👤 Childress Clyde
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-04 16:48
CPC Classifications
G; G03; G03C; G03C5/00; G03C5/02
Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
189 words
THE METHOD OF MAKING PHOTOGRAPHIC NEGATIVES HAVING TONAL COMPENSATED PRINTING CHARACTERISTICS WITH INCREASED CONTRAST IN THE AREAS OF MAXIMUM AND MINIMUM EXPOSURE COMPRISING EXPOSING A MONOCHROMATIC NEGATIVE FILM TO PRODUCE A LATENT IMAGE, DEVELOPING SAID NEGATIVE IN A DYE COUPLED DEVELOPER TO PRODUCE A COMPLETE SILVER IMAGE AND A DYE IMAGE, SAID DEVELOPER CONTAINING ONLY SUFFICENT DYE COUPLER TO PRODUCE A DYE IMAGE WHICH HAS ITS MAXIMUM CONTRAST IN THE AREA CORRESPONDING TO THE TOE OF THE CURVE OF THE DEVELOPED SILVER IMAGE AND THEREAFTER PROGRESSIVELY LOSES CONTRAST, SAID DEVELOPEMENT BEING CONTINUED TO DEVELOP SUBSTANTIALLY ALL OF THE SILVER IMAGE, FIXING AND RINSING SAID NEGATIVE AND THEN REDUCING THE SILVER IMAGE IN THE LOW DENSITY AREAS OF SAID NEGATIVE WITH A SELECTIVE REDUCER TO REMOVE THE SILVER IN THE AREA CORRESPONDING TO THE TOE AREA OF THE CURVE OF THE DEVELOPED DYE IMAGE AND TO LEAVE A SILVER IMAGE OF INCREASED PRINTING CONTRAST IN THE HIGH DENSITY AREAS OF THE ORIGINAL SILVER IMAGE, SAID COMBINED DEVELOPED DYE AND REDUCED SILVER IMAGES HAVING A DENSITY CURVE WITH INCREASED PRINTING CONTRAST IN THE SHADOW AND HIGH LIGHT AREAS OF THE CURVE.
Claim 2
Independent Claim
189 words
THE METHOD OF MAKING PHOTOGRAPHIC NEGATIVES HAVING TONAL COMPENSATED PRINTING CHARACTERISTICS WITH INCREASED CONTRAST IN THE AREAS OF MAXIMUM AND MINIMUM EXPOSURE COMPRISING EXPOSING A MONOCHROMATIC NEGATIVE FILM TO PRODUCE A LATENT IMAGE, DEVELOPING SAID NEGATIVE IN A DYE COUPLED DEVELOPER TO PRODUCE A COMPLETE SILVER IMAGE AND A DYE IMAGE, SAID DEVELOPER CONTAINING ONLY SUFFICENT DYE COUPLER TO PRODUCE A DYE IMAGE WHICH HAS ITS MAXIMUM CONTRAST IN THE AREA CORRESPONDING TO THE TOE OF THE CURVE OF THE DEVELOPED SILVER IMAGE AND THEREAFTER PROGRESSIVELY LOSES CONTRAST, SAID DEVELOPEMENT BEING CONTINUED TO DEVELOP SUBSTANTIALLY ALL OF THE SILVER IMAGE, FIXING AND RINSING SAID NEGATIVE AND THEN REDUCING THE SILVER IMAGE IN THE LOW DENSITY AREAS OF SAID NEGATIVE WITH A SELECTIVE REDUCER TO REMOVE THE SILVER IN THE AREA CORRESPONDING TO THE TOE AREA OF THE CURVE OF THE DEVELOPED DYE IMAGE AND TO LEAVE A SILVER IMAGE OF INCREASED PRINTING CONTRAST IN THE HIGH DENSITY AREAS OF THE ORIGINAL SILVER IMAGE, SAID COMBINED DEVELOPED DYE AND REDUCED SILVER IMAGES HAVING A DENSITY CURVE WITH INCREASED PRINTING CONTRAST IN THE SHADOW AND HIGH LIGHT AREAS OF THE CURVE.
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1959-03-06 | 1959-09-05 | 1960-03-06 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1963-03-06 | 1963-09-05 | 1964-03-06 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1967-03-06 | 1967-09-05 | 1968-03-06 | $7700.00 | Window Closed / Lapsed |