Bob Hayes - Director of Photography

originally called “Pepper’s Ghost”.  
In 1862, inventor Henry Dircks
developed the Dircksian
Phantasmagoria, a technique used
to make a ghost appear on-stage.
John Pepper was the first guy to
employ the technique on-stage and
“Pepper’s Ghost”. Remember the
early bird gets the worm but it is
often the second mouse that gets
the cheese. The technique was
quickly used in early filmmaking
and occasionally goofy guys like
me employ it out of nostalgia.

It simply involves placing a sheet of
glass in front of the camera at a 45
degree angle. Your primary set is in
front of the camera and the ghost
addition is placed to the side of the
camera surrounded by black.  The
intensity of the light on the subject
determines its visibility on the real
set.  It will always be somewhat
transparent and reversed.  If you
want the subject to move behind
objects on the real set you need to
create a black cut out on the ghost
set much as you would do a green
screen.

If you live in Los Angeles Knott's
Berry Farm has an amazing show
call the “Mystery Lodge” that is
driven by terrific Pepper's Ghost
techniques.

http://www.brcweb.
com/heritage/mystery-lodge.htm