objective measurement of image sharpness.

A measure of the sharpness with which the film can produce the edge of an object.

One of the key characteristics when judging the quality of images, acutance indicates the width of the boundary between black and white image areas . It is a central indicator of contrast and exceptionally good in gravure in comparison with other printing processes (cf. definition and resolving power).

In photography, acutance is used to describe the edge contrast of an image. Acutance can be more specifically defined as the amplitude of the derivative of brightness with respect to space. Due to the nature of the human visual system, an image with higher acutance appears sharper even though an increase in acutance does not increase real .