ABSTRACT
After an appropriate print exposure time for the significant highlights is found, shadow detail is fine-tuned with print contrast. Without a doubt, the universally agreed units to measure relatively short durations, such as exposure time, are seconds and minutes. However, when it comes to measuring paper contrast, a variety of systems are commonly used. Many photographers communicate paper contrast in form of ‘paper grades’, others use ‘filter numbers’, which are often confused with paper grades, and some photographers, less concerned with numerical systems and more interested in the final result, just dial-in more soft or hard light when using their color-or variable-contrast enlarger heads. Nevertheless, a standard unit of paper-contrast measurement has the benefit of being able to compare different equipment, materials or techniques while rendering printing records less sensitive to any changes in the future.
