Old Photo Processes

 
Albumen Print - Louis Désiré Blanquart-Evrard invented the albumen printing process in 1850. It became the dominant photographic printing process for the next 50 years. In this process, a piece of thin paper is coated with a mixture of albumen (egg white) and salt. The coated paper is immersed in a bath of silver nitrate and then dried in the dark. The dried paper is placed in a frame under a glass negative and exposed to direct sunlight for up to an hour until the image dark enough. There is no developing process. The image is fixed in a bath of sodium thiosulfate and often toned. Almumen prints are very subject to fading. (1855 - 1920)

Ambrotype - An ambrotype image is made by placing dark paper or cloth behind a glass negative. When seen in the proper light, the image appears positive. In 1854, Boston photographer James A. Cutting took out a patent for the process in which glass is coated with iodized collodion and then sensitized in a bath of silver nitrate. Over the next decade, many photographers sold ambrotypes in velvet-lined leather cases with brass mats. In this form, they resembled daguerreotypes, though they were cheaper to buy and simpler to make. Ambrotypes remained popular for portraiture through the Civil War, but were replaced by the cheaper tintype and carte de visite and became obsolete soon afterward. (1854 - 1865)

Cabinet Card - A photographic print attached to a cardboard mount measuring 4.25" by 6.5". The print was usually 4" by 5.5" but was sometimes smaller. One that I have has a 2.25" by 3" oval portrait. The Cabinet Card was introduced in Britain in 1863 by Windsor & Bridge. It gradually replaced the carte de visite in popularity about 1900 and continued in use well into the 20th century. (1863 - 1930+)

Carte de Visite - A photographic print (usually an albumen print) mounted on 2.5" by 4" card stock. The technique originated in France and crossed to America about 1859. The process became very popular and millions were sold during the height of its popularity between 1870 and 1880. These were often made by cameras which took multiple images from a single exposure. The carte de visite was replaced in popularity by the larger cabinet card about 1900. (1859 - 1900+)

Crayon Portrait - These large portraits were made from the 1860's into the early 1900's. In a crayon portrait, a weak photographic image provides the base for extensive handwork by an artist in charcoal or pastel. These were usually done on matte surface paper and were often near life size. The two examples that I have measure 16" by 20". (1860 - 1900+)

Daguerreotype - the first practical photographic process was developed by French artist Louis-Jacques-Mandé Daguerre and scientist Nicéphore Niepce in 1839. In its earliest form it was seldom able to produce portraits due to the lengthy exposure time required. A daguerreotype is made on a sheet of silver-plated copper. The silver surface is polished to a mirror-like brilliance. The plate is then sensitized over iodine vapor, exposed in the camera, and developed with mercury vapor. By 1840, experimenters had succeeded at increasing the sensitivity of the process. The earliest daguerreotypes tend to have bluish or slate grey tones; a brown-toning process called "gilding" came into widespread use in late 1840. Daguerreotypes have exceptionally fragile surfaces and were always furnished behind glass in frames or small folding cases. (1840 - 1855)

Tintype - The invention of Prof. Hamilton Smith of Ohio, begins as a thin sheet of iron, covered with a layer of black paint. This serves as the base for the same iodized collodion coating and silver nitrate bath used in the ambrotype process. First made in 1856, millions were produced well into the twentieth century. When tintypes were finished in the same sorts of mats and cases used for ambrotypes, it can be almost impossible to distinguish which process was used without removing the image to examine the substrate. (1856 - 19xx)