T_R_Oglodyte
TUG Lifetime Member
Look at this to boggle your mind.
Ames Window
The "window" is actually a trapezoid, not a rectangle. Our brain forces it to be a rectangle. But then, when the narrow side of the trapezoid comes toward us, our sense of perspective is thrown off, if it's a rectangle it can't be larger in back than in front. So our brain converts the rotating motion to an oscillating motion. The stick in the middle then gets all distorted because we see the stick rotating, as it actually is.
A way to see what's happening is to focus on the bottom of the video, so that you are viewing only the bottom edge of the window and the rotating cylinder to which the shaft is attached. If you don't look at the entire window, the illusion can be broken.
Ames Window
The "window" is actually a trapezoid, not a rectangle. Our brain forces it to be a rectangle. But then, when the narrow side of the trapezoid comes toward us, our sense of perspective is thrown off, if it's a rectangle it can't be larger in back than in front. So our brain converts the rotating motion to an oscillating motion. The stick in the middle then gets all distorted because we see the stick rotating, as it actually is.
A way to see what's happening is to focus on the bottom of the video, so that you are viewing only the bottom edge of the window and the rotating cylinder to which the shaft is attached. If you don't look at the entire window, the illusion can be broken.