Here is an interesting example of the concept of an “after image.” Your eyes have a “refresh rate” that sometimes leaves behind after images. The after-image color is always the complementary color of the original color. We spent a few days playing around with this concept in my color theory class my freshman year. Here is one of the more interesting demonstrations of this concept that I have seen.
Focus on the center “+”. In your periphery vision, you will notice that a green dot appears whenever the pink dot disappears. Now, keep focusing on that center “+” and eventually all of the pink dots disappear and you see a green dot circling around.
If you move your focus back to the dots, you will realize that this was just an illusion – the pink dots are all still there (Except for the rotating “lack of pink dot”).
[Via Outrageous Ebay Auctions (even though it has nothing to do with eBay)]
