Header of text saying Perceptual Stuff



Changes in the blue bands produce changes in the gray even though the value of gray is the same, a simultaneous contrast effect.


Mach Band Illusion


The brighter bands at 45 and 135 degrees are illusory. Victor Vasarely used variants of this figure in his art, and they are wonderful to see.


Vassarelly Illusion


The black areas fade to white and lead to interesting subjective contours of bright, white lines.


Mach Band Extension





Mach Band Extension




Mach Band like figures can contribute to a Cafe Wall effect.
All lines are horizontal and parallel.

Mach Band Cafe Wall Illusion



The following figure has a motion effect that some have described as "flowing electricity". Watch out. Some people feel dizzy. Obviously, stop looking if this happens. The illusion combines Mach Bands and stripes that resemble the BBC illusion (as described, many years ago by MacKay).


Mach Band BBC Illusion

For a larger version, go to the following link. (Remember to hit the "Back" button to return.)