Does anybody know about photos on glass?

We have a client that has a photo that is on glass. It dates back to around 1770. It is deteriorating on the backside and the customer would like to have it restored.

Any information about this type of photo would be great.

Thanks.

Since photography wasn't invented until the early 1800s I'd say you have something extremely valuable there. :)

I'd take it to a museum and see what they have to say.

Some old photos use glass as the substrate, so if you remove the glass there's nothing left but gelatin. I'd make a scan and get the original to safe storage as soon as possible. Lightimpressionsdirect.com has good storage materials.

What's 100 years or so one way or another? :D Don't get the image wet or you stand a chance of losing it, due to the gelatin becoming soft and sticky. Doug gave you good advice.

Ed

Doug and Ed are right. If what you say is true, you don't have an antique you have an antiquity. Something historically precious. Seek a museum or conservator about this for proper handling. If you do scan it, is it possible to upload a copy for us to see? You've really got me curious.
DJ

From the internet --

The glass image is likely to be an ambrotype.

"Ambrotype -- The Ambrotype image has a low contrast, grayish white appearance and consists of a glass plate supporting a collodion image, which is very similar to its cousin, the tintype (ferrotype process). The process was announced by the sculptor Frederick Scott Archer in 1851 and quickly became an inexpensive alternative to the daguerreotype."

Keep away from moisture, strong light, and heat. We have a member who is a professional conservator of photographs (Lampy -- Heather), and if she doesn't see this thread, you might PM or email her for some ideas about how to locate a conservator in your area.

For more on Ambrotypes, check out this (http://www.retouchpro.com/forums/showthread.php?s=&threadid=1364&highlight=Ambrotype) thread. Thomasgeorge gives a great deal of background on the Ambrotype...

--tks