A show that opened this week at the J. Paul Getty Museum in Los Angeles features dozens of authentic Rembrandt drawings -- and just as many that aren't. The idea is to reveal to museum-goers the tricks experts and art scholars use to identify his unsigned artwork, something the museum world rarely publicizes.

The "fake" Rembrandts in the Getty's show are all drawings attributed to the Dutch master painter for hundreds of years, until as recently as a few years ago. Over the past 30 years, new scholarship and cataloguing techniques have helped scholars determine that at least half of the more than 1,000 "Rembrandt" drawings were by others.