Polyrama Panoptique, French, 1820-1830.
© National Media Museum / Science & Society Picture Library
The Polyrama Panoptique was a miniature version of the diorama. The viewer looked in through the lens at a thin paper transparency, which was printed on both sides with different scenes. By operating the hinged shutter, the viewer could alternately light the transparency from the front or the rear. This produced a variety of transformations, which sometimes involved movement.