March 31, 2009

Magenta and other optical illusions

Fun post over at Forgetomori:
Magenta and all the colors of the grey matter
Above you can see the visible light spectrum, which can be understood as electromagnetic waves with different frequencies, going from the longer ones on the right to the shorter ones to the left. Go even lower and you enter the infrared, microwave and radio waves, go higher and you advance over the ultraviolet, X and gamma rays.

We see the visible light spectrum everywhere, and in a specially beautiful form in the rainbow. It�s common to think that the rainbow contains all the colors, so much so that the expression "all the colors of the rainbow" has 134,000 hits on Google, almost all of them referring to all the colors in the world.

Now, find magenta in the spectrum. It�s simply not there. All the colors of the rainbow do not contain the magenta. How can we see it then? Is it a �magical color frequency� that don�t actually exist?

An article from Liz Elliot suggested last month by the folks of BoingBoing provoked a lot of discussion by claiming quite simply that �magenta ain�t a color�. It sounds unbelievable and yet�

And yet, well, it�s not actually true. Keep reading because the amazing thing is, the truth is even stranger.
A couple other optical illusions including my favorite:
grey-square-optical-illusion.jpg
Print out two copies and cut one of them in half with the cut line running down the middle of Square A. Move the cut piece of paper over to that the half of Square A overlaps about half of Square B. Heh... Posted by DaveH at March 31, 2009 7:52 PM