Visual Performance on Perceptual Tasks at Low Photopic Brightnesses

Subjects, rigorously screened for visual abilities, were tested on a variety of visual perceptual tasks. A brightness range of 0.005 to 6.0 ft-L (at the subject's eye) was used. For each task a critical brightness level (approximately 0.02 to 0.05 ft-L) was found, below which visual performance was impaired (as measured by speed and accuracy scores), and above which increases in brightness produced little or no improvement in visual performance. Implications are discussed.

Print ISSN

0898-042X

Published

1951-09

Content type

Original Research

DOI

10.5594/J11333