Museum Ghost

On a visit to a "haunted" museum, a BBC journalist snapped this intriguing pic which allegedly shows a ghostly apparition.
Click on the post title for the full story at BBC News and an enlargeable version of the pic.

To me it looks like a shirtless dude with his pants belted above his belly and a rag on his head. Why my deceased uncle is apparating (to use Harry Potter jargon) at a museum in the UK ? That's the real mystery.