A sophisticated X-ray technology is paving the way to uncover the secrets of a 380-year-old masterpiece by Rembrandt van Rijn, Old Man in Military Costume. Painted by the Dutch artist during 1630–1631, previous investigations spotted another portrait, an underpainting, that was only faintly distinguishable even after experts applied three different techniques to uncover it. For years art historians have speculated about who is depicted under the surface portrait.

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