I am a fan of afterimage illusions like this….
I thought that it would be fun to use the effect to create nonexistent rainbows. To experience this dramatic and lovely effect just stare at the dot in this image for 20 seconds and then look out of the window at a patch of blue sky (it might be helpful to click on the image to open it up full size before you start).
Did it work for you? Enjoy the effect?