Finally, the mystery of the panel consisting of patches glued together is also solved in the lecture. Actually, the wood panel was later enlarged to make it more grand and valuable, but the original painting was painted on a single panel, as Rembrandt would have done it. Furthermore, the wood is of the same tree used in other Rembrandt paintings, like the "Self-Portrait with a Hat”.
All this information points to Rembrandt as the painter of the controversial painting.