Part of the glass ceiling at the National Gallery, East Wing. I can't even begin to describe how much trouble this ended up being, from the guard with whom I had a fight because he insisted my leather purse was a backpack and couldn't be worn as such, to trying to get an adequate capture of the ceiling in the quickly disappearing light, to processing the images because of the lens distortion, line distortion and multicolor, multi-tone fringing. What a nightmare :-). Anyway, this was the one I came up with.