Perhaps the most famous painting in history, Leonardo Da Vinci's "Mona Lisa" is also among the most closely scrutinized — and one scientist has capped a decade of study with the claim (PDF) that underneath that enigmatic smile lies a second, different portrait, perhaps even of a different person.
Pascal Cotte commenced his study of the "Mona Lisa," known in France as "La Joconde," in 2004, when he was granted access by the Louvre in Paris to photograph the painting in a variety of wavelengths of light — an early version of a technique now known as multispectral imaging.
These many exposures all produce slightly different images, and studying these differences can reveal previously hidden details — or, as Cotte claims, a significantly different painting underneath the first.
In a reconstruction based on traces Cotte observed, a woman looks not at the viewer but past them, and while her posture is the same, the features of the face are different and her dress is fancier. Leonardo later painted over this to produce the painting we now see, Cotte claims, but these new details may help determine the identity of the "Mona Lisa,"— a question that art historians have speculated about for centuries.
It has also been suggested that Leonardo may have painted an earlier version of the "Mona Lisa," though some critics aren't convinced.
Cotte is publishing a book on the topic, and the BBC in a video report consulted several experts on it. Some were enthusiastic about the research; others not so much. Cotte's company, Lumiere Technology, has performed similar work on other paintings as well, notably Leonardo's "Lady With an Ermine," discovering small details that may aid in their restoration.