Color Optical Illusions

image source.

A frequently used optical illusion is the after-image. Stare at an image for x number of seconds, then look quickly to a blank wall and voilà! You get an entirely different image, which was burned into your retina while you stared so intently at a previous one.

In Josef Albers' Interaction of Color, his explanation of the phenomenon is definitely plausible. Overexposure to one color will fatigue the cones that receive those colors, so the after-image will consist of the complimentary colors of the original image. I know that this is true from experience. When I find myself staring at a vividly red object for a prolonged period of time, I get a green after-image once I look away.

One other interesting concepts in Josef Albers' Interaction of Color is subtraction of color. At first glance, the center squares in plate VII-4 on page 89 look almost the same, but when the background color is taken away, the differences are drastic. The two colors aren't even of the same shade or hue at all, but the fact that the contrasting ground colors were able to make a tannish yellow appear similar to a mossy green is nothing short of amazing.

In fact, the text of my blogs may appear white against the black background, but in reality, it's more of a washed out gray. This is white. It's hard to believe that the two colors aren't the same, but once the word "white" has been changed to white, the stark contrast pops out against the sea of now-visible gray.