Yesterday we took a trip to Old College and learned about the different types of old fashioned photography. Some of the different processes used are Ambrotype, Deguerotype, Tin Type, and Cyantype. Ambrotypes are glass negatives with black background. Deguerotypes are made on a copper plate, and have a bright mirrored surface. Back in the 1800s it would take 15 minutes to take a photo! However, some of these processes are still used today. I found it really interesting to learn that there are so many different processes.
Here is a link to a website which talks about the Cyantype process:
http://www.nationalmediamuseum.org.uk/pdfs/photoCYANO.pdf