Patent · US Expired

Method and device for selecting the appropriate contrast grade photographic for printing a black and white transparency

US4885607A · kind A · utility

2Cited by
2References
5Claims
0Family size

Inventor

Key dates

Filing dateSep 14, 1988
Grant dateDec 5, 1989
Priority date
Expiry dateSep 14, 2008

Classification

  • Technology area (CPC G)Physics
  • CPC primaryG03B27/72
  • WIPO fieldOptics
  • WIPO sectorInstruments

Abstract

A device and method for selecting a contrast grade of paper or variable-contrast filter for printing a black and white negative utilizing a clear substrate having a plurality of sections, each section having a different color equivalent to a different variable contrast filter and each section having approximately the same density.

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.