Two gray squares that have the same luminance value may appear to be different in a scene. This effect is due to the fact that

Question

Quizplus · Accepted Answer

Retinal ganglion cells and geniculate cells are known to respond more significantly to differences in contrast rather than absolute luminance levels. This means they are more sensitive to how light or dark an object appears relative to its immediate surroundings, rather than the actual or absolute brightness of the object. This contrast sensitivity is a fundamental aspect of how visual information is processed and can lead to the perception of different shades or brightness levels under varying contextual visual environments, even if the luminance value remains constant.

Two Gray Squares That Have the Same Luminance Value May