Leonardo Da Vinci's "Mona Lisa" painting may be part of the oldest 3D artwork, say two visual scientists. In 2012, scientists discovered that beneath layers of black paint, a seemingly insignificant "knock-off" of the "Mona Lisa" in the Museo del Prado in Madrid was in actuality very close to the original hanging in the Louvre Museum in Paris, revealing the same subject with the same mountain landscape background. That painting may have been painted by Da Vinci or possibly one of his students.
"When I first perceived the two paintings side by side, it was very obvious for me that there is a very small but evident difference in perspectives," study researcher Claus-Christian Carbon of the University of Bamberg in Germany wrote in an email to Live Science ( via livescience.com ).
"Maybe the view of a perceptual psychologist is highly sensitive for such tiny differences, but it is very clear that also persons who are not so strongly involved in perceptual sciences can see it easily after having received information on the change in perspective."