Photography has beenaround for a long period of time, and despite the many different earlyphotographic processes, perhaps 3 main ones stood out: Daguerreotype,Ambrotype, and Tintypes.
In particular, ambrotypeis one of the many early photographic processes used to develop and “print”photographs. The ambrotype process is documented to have been created by JamesAnson Cutting in 1854 however, it is stated that the process was actually firstused by Frederick Scott Archer 3 years prior to Cutting, to create some of the earliestportraits of this method. Before ambrotype, another process known as daguerreotypewas very popular. Ambrotype had easily overtakendaguerreotype in demand and usage as soon as it came out mainly because it was easierto view and not as expensive to produce. The main reason for this was becauseunlike daguerreotype, ambrotype did not have a surface that is mirror-like orshiny which made viewers have to tilt the photo to a certain angle to be ableto see the image. Ambrotype was alsocheaper to produce and required a shorter exposure time in order to capture animage. Ambrotype is basically positive photographs that have been exposed onto glass.Nevertheless, it must be noted that the glass itself when the image is producedis actually negative.
However, as it is often placed against a dark background, the image appears positive. To put itsimply, ambrotype was a glass plate that was covered with collodion that containediodide and then put into a silver nitratesolution, making it so that the glass is sensitive to light and able to beexposed to produce an image; the glass must still be wet in order to work. Todevelop the image, the glass must be developed in a solution that contains bothof nitric acid and iron sulfate and thenbathed in either sodium thiosulfate or potassium cyanide. The glass will thenbe dried. With that, a negative image is actually produced or printed.
Evenafter drying, oftentimes a transparent varnish will be used over the image. Asthe last step of printing, a dark background is then placed with the glass tocreate a positive image. In fact, the dark background sometimes creates a certain depth of the image.