An age-old artwork can sometimes distort the truth. This was certainly the case for Rembrandt’s “Portrait of a Young Woman” at the Allentown Art Museum, in Pennsylvania. For more than four decades, visitors to the museum viewed the portrait not as a work by Rembrandt but by his workshop.  In the 1970s, art experts mistakenly deattributed the portrait because conservators over the centuries had altered it to such an extent that it was deemed unrecognizable as a Rembrandt original.  Today, the portrait has been restored and is back on display—as a painting by Rembrandt—in the museum’s exhibition “Rembrandt Revealed.” The exhibition reveals why the portrait was deattributed and how it was reattributed to Rembrandt. The exhibition also gives interesting insights into the process and challenges of art attribution.  Not Rembrandt  In the early 1920s, art scholars began to question whether the artwork had actually been painted by the Dutch master. In …