Luminance thresholds of the water-immersed eye

Luminance thresholds were measured for the water-immersed eye as a function of adaptation level, viewing distance, and turbidity of the water, and compared to standard adaptation curves. In water, thresholds varied as a function of initial adaptation level, and the rate of adaptation paralleled that for the eye in air. However, thresholds were about 1-2 log units higher for the water-immersed eye than for the eye in air at all adaptation levels.