A three-panel photo booth, which allows the subject to be photographed against a variety of backdrops wearing or holding a variety of props. She can take a picture of herself or someone else can take a picture of her. He can sit or stand on a sturdy cardboard tube stool. Once he’s done, he can leave his prop(s) in/on the nearby box/wall of props.
By putting on a beak or a top hat with spires, the visitor is merely disguised, but his shadow, having integrated the prop into itself, is transformed. This new shadow is evidence of the subject’s transformation. He can choose to include it in the photograph or not.