Contrast Effects

Try counting the number of black dots in the grid:

The black dots you see are fleeting, and any individual dot will turn white as soon as you focus on it. Clearly, all the dot are actually white, yet at a glance we still perceive some of them as being black.

The unsettling effect seen in this image (called a Hermann Grid) is one of many optical illusions that take advantage of the way our visual system processes contrast information. Let's take a closer look at how it works.

prev [1 2 3 4 5 6 7] next