A French post about the anamorphic optical illusions (on Tutoweb).
Anamorphoses
The spinning dancer
As a matter of fact, this optical illusion from Japanese designer Nobuyuki Kayahara comes from the total lack of 3rd dimension data in the image. Nobody can formally determine the rotation direction of the dancer. But the brain must take a decision. So, it chooses, but can be easily perturbated and changes its mind. Then, the dancer starts spinning in the other direction (some people may not be able to see the change, probably because their brain has some kind of preference).
Source: NY Times.
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Hering illusions
This optical illusion is based on the crossing of lines and curves. Straight lines appear curved.
Samsung is only an illusion
Or so it would seem that advertisers want you to understand, if you follow this ad from Samsung. In less than 2 minutes, we’re guided through 10 good optical illusions.
Following in the footsteps of…
This web site will present optical illusions from all origins.
All you need to know for now is that it is working from what originated in Roumazeilles.net optical illusions category of posts. They were worth their own web site, no?
Nota: French version.