The Salt and Silver exhibition is a collection of pictures between 1840-1860 to tell the history of the beginning of photography. The display is divided into four sections: paper photography, modern life, epic and presence.
There is a small information about Willian Fox Talbot’s life and some of his prints using salt technic in the first room. The prints are interesting and it is a wonderful opportunity to see them. However, to be honest, I missed some explanation about the technical process. In the end, I was frustrated because there were few historical information and nothing about technic. However, I decided to search online how Talbot did his prints. I found, at the Ilford website, a guide summarising the idea and explaining the salt and silver method. In order to produce light-sensitivity, a sheet of paper is washed with a solution of salt (sodium chloride), followed by coating one side only with silver nitrate. The paper is printed, after dried, on strong sunlight exposure. The sensitive side is putted up, directly under a negative and beneath a sheet of glass within a printing frame.The exposure time is approximately two hours and needs to be determined by visual inspection. After that, a hypo solution (sodium thiosulphate) is used to fix the print. Then, the paper is washed and dried. (http://www.ilfordphoto.com/aboutus/page.asp?n=128)
It is possible to see, in the third room, some albumen printings. In 1951, this formula was discovered and displaced the salt one. Besides the method, the difference between both is the color and sharpness. The albumen is sharper and proximately of sépia color while salt and silver prints are softer and the color is a mix of magenta and brown.
1) Salt and Silver
My favorite room was the last one. I could see the beginning of portrait and documentary photography. Amazing!