The Effect of Aberrations upon Image Quality

Lenses are used to form images for two principal purposes first, to produce the most accurate record possible of the original object; and second, to produce a pleasing effect. The character of the image formed by a lens depends upon diffraction and upon the residual aberrations remaining after the designer and the manufacturer have done their best. For pictures of the first type it is desirable that aberrations be reduced to a minimum, but for pictures of the second type they are very often deliberately employed to produce desired effects. In motion picture projection, lenses of the first class are doubtless always desired. In motion picture photography, some attention has been given to achieving special effects by deliberately introducing aberrations into the lens. — Among the many aberrations that afflict lenses, one of the most important is chromatic. Since, in general, only two colors can be brought to a common focus, some thought has been given to the question of what two colors it is best to choose to meet the requirements of various kinds of lighting and different types of sensitivity of the emulsion. Recent experiments indicate that for a combination of particular interest in motion picture photography, namely, incandescent lighting and super-pan emulsion, no significant difference in performance is detectable among lenses of 12-inch focus or less, depending upon whether the two colors chosen for chromatism are yellow and violet, or red and violet.

Print ISSN

0097-5834

Published

1937-04

Content type

Original Research

DOI

10.5594/J08551