Purkinje effect
TENDENCY FOR THE PEAK LUMINANCE SENSITIVITY OF THE HUMAN EYE TO SHIFT TOWARD THE BLUE END OF THE COLOR SPECTRUM AT LOW ILLUMINATION LEVELS
Purkinje shift; Purkinje Effect; Purkinje lights; Purkinje phenomenon
The Purkinje effect (; sometimes called the Purkinje shift, often incorrectly pronounced ) is the tendency for the peak luminance sensitivity of the eye to shift toward the blue end of the color spectrum at low illumination levels as part of dark adaptation. In consequence, reds will appear darker relative to other colors as light levels decrease.