The relationship between illuminance and brightness

When two areas of the same brightness appear to have different brightness' dependent on their backgrounds

When two areas of different brightness appear to have the same brightness dependent on their background

When two areas of the same brightness appear to be the same brightness dependent on their backgrounds

When two areas of different brightness appear to have different brightness' dependent on their backgrounds

Lateral inhibition

Simultaneous inhibition

Lateral facilitation

Simultaneous facilitation

Increased brightness creates a stronger response when this is within the on center, but creates a stronger inhibitory response when within the off surround

Decreased brightness creates a stronger response when this is within the on center, but creates a stronger inhibitory response when within the off surround

Decreased brightness creates a stronger inhibitory response when this is within the on center, but creates a stronger response when within the off surround

Increased brightness creates a stronger inhibitory response when this is within the on center, but creates a stronger response when within the off surround

A uniform grey going from dark to light appears to have brighter bars separating it

A set of grey bars going from light to dark, separated by lighter bars appear to be a uniform grey

When looking at the lighter bands there appears to be a grey dot in the intersection

The contrast within a uniform grey appears unchanged

Black squares spaced apart on a white background, grey dots will be perceived in the intersections

White squares spaced apart on a black background, grey dots will be perceived in the intersections

Black squares spaced apart on a white background, grey dots will be perceived in the square centers

White squares spaced apart on a black background, grey dots will be perceived in the square centers

Perception only cares about the contrast (edges) and properties that help determine edges, not the retinal image

Perception does not care about the contrast (edges) and properties that help determine edges, only the retinal image

Perception cares about both the contrast (edges) and properties that help determine edges, and the retinal image

Perception only cares about neither the contrast (edges) and properties that help determine edges, or the retinal image