VISUAL PERFORMANCE IN ASTRONOMY NEAR THE SCOTOPIC THRESHOLD PART 1: TEMPORAL INTEGRATION

摘要

The integration time of vision near the scotopic threshold was measured for four observers while viewing astronomical targets. This appears to be the first time such measurements have been made using natural targets in the night sky. The targets included: (1) a point source (a faint star), (2) an extended complex white-light source (a spiral galaxy), and (3) extended dark structure in a line-spectrum source (silhouetted dust in an emission nebula). Integration times were, respectively: (1) 0.92 +- 0.14 s, (2) 0.32 +- 0.14 s, and (3) 0.57 +- 0.19 s (averages with standard deviations).