@cjphoto a most interesting observation. In fact the chair back, while being level across the top, does have a curve in it from front to back so the shadow allows us to see that even though the chair doesn't show it. A fact I failed to notice until you mentioned it!
@grammyn - The same happens in my photos too. Someone will mention something that I clearly didn't even see. Haha. But it's cool to know where the curve comes from.
