http://ca.news.yahoo.com/photos/baffling-%E2%80%98star%E2%80%99-illusion-keeps-on-turnin%E2%80%99-turnin%E2%80%99-turnin%E2%80%99-slideshow/

http://l.yimg.com/bt/api/res/1.2/7NTUhzLay7KASyFlM14jBQ--/YXBwaWQ9eW5ld3M7Zmk9aW5zZXQ7aD0zNTU7cT04NTt3PTM1Nw--/http://l.yimg.com/os/446/2012/03/26/kaleidoscope-illusion-gif_233853.gif

Which of the two colored shapes in this illusion is rotating? If you guessed ‘both,’ guess again. Only the outer red ring is actually moving; the blue inner core is stationary. But every time the star-shaped projections on the two objects line up perfectly, the blue shape appears to ‘jerk’ backwards, or counter-clockwise, almost like a gear slotting into place. What causes the illusion? Dutch mathematician and cognitive psychologist Dr. Peter A. ...

Nice one, Obtuser.  It's amazing how the blue shape appears to move even after you know how the illusion is done.

Nice one, Obtuser.  It's amazing how the blue shape appears to move even after you know how the illusion is done.

Yes, that is prime!
Did you get around to all of the others in this link I picked it up on Yahoo.ca after signing out of Mail? That is quite a batch for all one sitting!

http://www.youtube.com/watch?v=QKCSBkdEUXQ&feature=player_embedded#!

: Ken in Berkeley  April 01, 2012, 02:49:14 PM

Nice one, Obtuser.  It's amazing how the blue shape appears to move even after you know how the illusion is done.

Yes, that is prime!
Did you get around to all of the others in this link I picked it up on Yahoo.ca after signing out of Mail? That is quite a batch for all one sitting!

I did get around to looking at some of the others Obtuser, but there are only so many that a guy can look at in one sitting.

Obtuser,

One of my favorite optical illusions is the Checker Shadow Illusion.  Look at the square marked A and the square marked B.  The squares are different shades of gray, right?  Wrong!

http://web.mit.edu/persci/people/adelson/checkershadow_illusion.html