On the right you see the painting “All is Vanity” by Charles Allen Gillbert (1873–1929). Place mouse over image and observe the change.
This is not an “optical illusion” proper, it’s more a physical effect: With the strong spatial low-pass filtering, the blurred version simply lacks the fine details. However, one could also argue that the low-spatial frequency information is masked by high spatial frequencies like in the“Lincoln effect” by Harmon & Julesz (1973) “The recognition of faces”. Related paintings are depicted below; feedback educating me on the unknown sources is welcome.
I owe the original slide to Prof. Mackensen.
Interesting background on skulls in culture & art.
|Def Leppard album ‘RetroActive’||Wotherspoon ‘Gossip, and Satan came also’||Wotherspoon ‘Society, a portrait’||Dali ‘Voluptate Mors’ (Photo: Halsman) [Orwell on Dali]||Dali ‘Ballerina’||Cher, album ‘Heart of stone’|
|‘L'Amour de Pierrot’ ≈1905||Au revoir!||‘La famille Impériale de Russie’ (French post card ≈1908)||Cat or Couple? (unknown)||French postcard|
(on Planet Perplex)
|Judge Magazine cover, 1894 “Death to our industries!”|