We have two Pepper's ghosts at our museum - a Chinese herbalist and a John
Muir ghost.  The effect is created just as some others have already
explained - there is an image reflected off a 45 degree sheet of glass.  In
our case, the source is a 56" rear-screen projection television that is
mounted facing down at ceiling level, out of sight of the visitor. (In one,
it's outside the window of a cabin; in the other, it's behind a counter &
cabinets.)  The image, which is mirror-image inverted, then projects off the
sheet of glass toward the visitor.  The visitor has to be kept back a
certain distance in order for the illusion to work properly, which is
achieved in one case by a bar partition, and in the other by the counter.

We have found our ghosts to be quite popular - I enjoy hearing kids run over
to their classmates or parents to tell them about the "ghost."  It's a
pretty simple technology, and we haven't had any problems, except that one
of the televisions did break down and had to be replaced (it was still under
warranty, thank goodness!)

In reply to Lisa's question about the origin of the term, my understanding
is (I could be wrong) that in the 19th century, there was a magician by the
name of Pepper who pioneered this technique in his magic shows.

Feel free to contact me if you need any more detail.

Amanda Meeker
Golden State Museum
1020 O Street
Sacramento CA 95814
http://www.goldenstatemuseum.org <http://www.goldenstatemuseum.org>
[log in to unmask]


        ----------
        From:  prospero [SMTP:[log in to unmask]]
        Sent:  Thursday, December 02, 1999 4:40 AM
        To:  [log in to unmask]
        Subject:  pepper's ghost

        The museum I work at is thinking of adding several exhibits in one
of our
        halls.  Someone suggested using a device called "peppers ghost."
I've
        looked on the web and found it is a sheet of glass reflecting an
image in
        front of a 'scene'.  I was wondering if anyone has created a display
using
        this technique and if they would share any of problems or solutions
they
        encountered.  Thanks for the help.

        James Crawford
        Preparator
        Rochester Museum and Science Center
        Rochester, NY

        =========================================================
        Important Subscriber Information:

        The Museum-L FAQ file is located at
http://www.finalchapter.com/museum-l-faq/ museum-l.html. You may obtain
detailed information about the listserv commands by sending a one line
e-mail message to [log in to unmask] The body of the message
should read "help" (without the quotes).

        If you decide to leave Museum-L, please send a one line e-mail
message to
        [log in to unmask] The body of the message should read
"Signoff
        Museum-L" (without the quotes).

=========================================================
Important Subscriber Information:

The Museum-L FAQ file is located at http://www.finalchapter.com/museum-l-faq/ museum-l.html. You may obtain detailed information about the listserv commands by sending a one line e-mail message to [log in to unmask] The body of the message should read "help" (without the quotes).

If you decide to leave Museum-L, please send a one line e-mail message to
[log in to unmask] The body of the message should read "Signoff
Museum-L" (without the quotes).