July 5, 2011 6:14 PM Subscribe
An optical illusion based on retinal fatigue allowing you to "see" an "impossible color"?
posted by darkstar to science & nature (10 answers total) 21 users marked this as a favorite
Herodios' recent comment
on Impossible Colors reminded me of a link I'd seen here before and was hoping to get help finding it again.
Someone posted a link on MeFi within the past couple of years, I think, about "impossible colors" and linked to a page that had an optical test. In the test/illusion, I seem to recall that you stared at a color or pattern for a while and then closed your eyes. Alternately, you then stared at a white background.
The residual image left from the retinal fatigue was an "impossible color" that you couldn't normally see in nature. A kind of fluorescent greenish-yellowish-blue, if I recall.
Anyone remember that link? (Note: it's not the one on the "Impossible Colors" wikipedia article page for the yellow/blue overlap.) I'd love to share it with my students in our upcoming chemistry lecture dealing with spectroscopy.