Professor:
　　Everything you just read about "Portrait of an Elderly Woman in a White Bonnet" is true, and yet after a thorough re-examination of the painting, a panel of experts has recently concluded that it's indeed a work by Rembrandt. Here is why.
　　First, the fur collar. X-rays and analysis of the pigments in the paint have shown that the fur collar wasn't part of the original painting. The fur collar was painted over the top of the original painting about a hundred years after the painting was made. Why? Someone probably wanted to increase the value of the painting by making it look like a formal portrait of an aristocratic lady.
　　Second, the supposed error with light and shadow. Once the paint of the added fur collar was removed, the original could be seen. In the original painting, the woman is wearing a simple collar of light-colored cloth. The light-colored cloth of this collar reflects light that illuminates part of the woman's face. That's why the face is not in partial shadow. So in the original painting, light and shadow are very realistic and just what we would expect from Rembrandt.
　　Finally, the wood panel. It turns out that when the fur collar was added, the wood panel was also enlarged with extra wood pieces glued to the sides and the top to make the painting more grand and more valuable. So the original painting is actually painted on a single piece of wood, as would be expected from a Rembrandt painting. And in fact, researchers have found that the piece of wood in the original form of "Portrait of an Elderly Woman in a White Bonnet" is from the very same tree as the wood panel used for another painting by Rembrandt, his "Self-portrait with a Hat".