Relationship between Definition and Resolving Power with Test Objects Differing in Contrast

It has been shown that the resolving power of a particular photographic system for a test object having a high contrast is not a unique measure of the subjectively determined definition of pictures made with the system. This work is extended in the present study to include the case where the resolving power of the negative as used in the system is determined with both a high-contrast and a low-contrast test object. The low-contrast resolving-power values do not correlate significantly better with definition than the high-contrast values, and neither give a unique measure of definition. Thus the generalization that low-contrast resolving power is a unique measure of definition is not justified.