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Salt
Prints
As mentioned earlier, William Henry Fox Talbot patented a new process in 1841.
This process became the first system to use a negative and a positive and
allowed the photographer to produce positive prints in great quantities. Through
additional refinements, one of the chemicals used to make the print more
sensitive to light was sodium chloride (table salt)...Thus it acquired the name
of salt print. It was soon noticed that these prints were subject to
fading and that it was necessary to remove the fixer or the hypo from the paper.
The normal identification features of a salted paper print are a smooth but dull
surface, an obvious lack of very fine detail and a silver image located in the
fibers of the paper support rather than confined to the surface. Depending upon
the choice of papers and methods of altering the image tone, salt prints were
made to have a wide variety of color hues, ranging from brick red to a rich
purple-black. Since many of these prints were produced before the importance of
fixing, washing and toning were realized, countless have suffered serious
fading. Salted paper prints were popular from 1839-1860.
Albumen
Prints
A further improvement over the Salt Print was introduced by Louis-Desire
Blanquart Evrard in 1850. Initially, photographers prepared their own albumen
paper by coating a thin sheet of paper with egg white...hence the name albumen
print. The albumen served to hold the light sensitive silver salt on the
surface of the paper. After drying it was used in the same manner as
salted-paper, with the image being formed by the darkening properties of the sun
on the chemicals (like a suntan for the prints). For both aesthetic and
preservation reasons, the prints were toned with gold-chloride, which gave the
image a rich purple-brown color. Albumen paper was widely used throughout the
world and the majority (80%) of the surviving photographs of the 19th century
are on albumen paper. That is why it is important for you to be aware of this
material's susceptibility to factors which cause deterioration. It is fairly
easy to learn how to identify albumen prints. With careful examination and under
magnification it is possible to clearly see the paper fibers through the
albumen. Many albumen prints show a very fine lateral cracking of the overall
glossy surface. The paper support is very thin and coated with albumen. Early
gelatin and collodion papers were made to imitate the look of albumen papers and
may confuse the inexperienced examiner. Because albumen tends to yellow, an
albumen print will almost always have yellowed highlights (light areas). Due to
the thinness of the paper, most albumen prints were mounted onto stiffer papers
and cardboards. A popular format was the Carte de Visite. Other formats are
listed in addendum A. These support boards and the adhesives used to hold the
print to them contribute very significantly to the conservation problems of
albumen prints. Characteristically, albumen prints begin to lose density in the
lower density (lighter) areas, thus losing highlight detail and reducing
contrast. With time, as the silver continues to be attacked by sulfur and other
elements, the image changes from the cooler purple-brown to a warmer
reddish-brown. It is very important to understand that prints that are in
relatively good condition due more to chance than through a careful program of
preservation may not remain so if exposed to harmful conditions of high humidity
and temperature or exposure to oxidants and sulphiding agents. Therefore, high
standards of storage and display are required to prevent deterioration of the
image quality.
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