Ambrotype Photograhic Images
In 1851 the Englishman Frederick Scott Archer (1813 to 1857) invented the wet collodion process or ambrotype, as it is commonly known. Unlike the daguerreotype process that was expensive and time consuming, ambrotypes could be produced in a matter of seconds with great clarity and at a fraction of the price of daguerreotypes.
Technical Development:
The ambrotype process involved the use of a glass plate as a base medium that was coated with collodion. This was a substance which Scott Archer happened upon a few years before, when it was being used by military doctors as a type of liquid bandage, as it produced a clear waterproof film. Scott Archer experimented and came up with a formula that worked by mixing collodion with potassium iodine and then immersing this in silver nitrate. This was then applied to a glass plate. After development the negative image was backed with an opaque material, resulting in a positive image. The glass negative/positive was very fragile and would be covered by another piece of glass for protection and subsequently housed in a frame or case. Like the daguerreotype, each ambrotype image is unique.
The collodion medium dried rapidly so that both exposure and development could occur while the plate was still in the camera and still wet. A photographer had to work quickly and this presented some obvious challenges for the travelling photographer. In addition to the camera and ancillary equipment a portable darkroom was also needed.
Commercial Development
Scott Archer did not take out any patents on his discovery because it was never his intention to make money. During his lifetime he never received any recognition for his gift to photography and he died penniless. James Ambrose Cutting (1814 to 1867) took out the patent rights in the U.S. in 1854 and with his partner Isaac Rhen traveled the U.S. selling licenses for the process. The ambrotype was a giant leap forward enabling the average person to have their portrait taken. Soon photography studios were producing ambrotype images across America. With photography now being opened to the masses, the range of images produced was endless. Skilled photographers, either in galleries or traveling around the country could photograph practically anyone or anything.
Collector Information:
As would be expected, the larger plates sizes command higher prices as do outdoor and occupational images and animals. The most common images are studio portraits and are readily available for the collector even today. The prices for ambrotype images range from a few dollars to a couple of thousand.
Ambrotypes were produced in the following standard sizes:
Whole plate 6.5″ by 8.5″
Half plate 4.25″ by 5.5″
Quarter plate 3.25″ by 4.25″
Sixth plate 2.75″ by 3.25″
Ninth plate 2″ by 2.5″
Sixteenth plate 1.375″ by 1.625″.
The ambrotype was a very popular medium well into the mid 1860′s. It then went out of favor in the U.S. around 1865, mainly due to increased popularity of the paper image. However in Great Britain it continued to be used, alongside paper images, until the early 1900′s.
Reference note by p4A.com Contributing Editor Robert M. Ginns.