Shadow Passes for the Mona Lisa

"For a long time, scientists and curators have wondered how da Vinci created shadows on her face with seemingly no brushstrokes or contours. Art experts call this shadowing technique sfumato—like the Italian word for smoke, fumo."

Leonardo was perhaps the first honorary member of the Visual Effects Society.

http://www.economist.com/node/16635928?story_id=16635928&fsrc=scn/tw/te/...