The Role of Resolving Power and Acutance in Photographic Definition

The method of measuring resolving power and the factors that influence the measured value are first described. The concept of acutance, which is an objective quantity that correlates with sharpness, is then explained. Experiments have shown that no unique correlation exists between definition, which is the quality aspect of a photograph that is associated with the clarity of detail, and either resolving power or acutance. A good correlation was found between acutance and definition, provided the resolving power was greater than about twice that of the eye for the conditions under which the photographs were viewed. A correlation with acutance was also found for lower values of resolving power when the acutance was weighted with a suitable function whose parameters depend on the resolving power and the conditions of viewing.

Print ISSN

0361-4573

Published

1956-01

Content type

Original Research

DOI

10.5594/J04791