There's also a National Geographic program on this one, and the illustrations are quite compelling. A superimposed image of the Mona Lisa on da Vinci's self portrait is startling. I wonder if books on history of photography should be reviewed to include a note on da Vinci. He was a master of the hidden meaning! :) Elson Chris wrote after viewing http://origin.island.lk/2002/04/13/satmag02.html: > I had a look at this web page, very impressed. We had an article on the > camera obscura and painting on TV. It was in use by Venice and by Rome in > the 14th century. Many of our "old masters" are painted with its aid. > People must have thought of using a chemical to paint directly with light. > They just died and their images with them.