https://x.com/AkiyoshiKitaoka/status/1798705648001327209
The left face appears whitish and the right one blackish, but they are made up of the same luminance.
https://community.wolfram.com/groups/-/m/t/3191015
Illusory staircase Gelb effect
https://www.psy.ritsumei.ac.jp/akitaoka/illgelbe.html
https://persci.mit.edu/gaz/publications/gazzan.dir/figure20.html
Figure 20: The snake illusion. All diamonds are the same shade of gray. (a) The regular snake: the diamonds appear quite different. (b) The “anti-snake”: the diamonds appear nearly the same. The local contrast relations between diamonds and surrounds are the same in both (a) and (b).
Back to E. H. Adelson, Lightness Perception and Lightness Illusions