Collodion is a flammable, syrupy solution of pyroxylin in ether and alcohol.
There are two basic types: flexible; non-flexible.
The flexible type is often used as a surgical dressing or to hold dressings in place.
When painted on the skin, collodion dries to form a flexible nitrocellulose film.
While it is initially colorless, it discolors over time.
Non-flexible collodion is often used in theatrical make-up.
History In 1846 Louis-Nicolas Ménard and Florès
Domonte discovered that cellulose nitrate could be dissolved in ether.
They devised a mixture of ether as the solvent and ethanol as a diluent that rendered cellulose
nitrate into a clear gelatinous liquid.
Collodion was first used medically as a dressing in 1847 by the Boston physician John Parker
Maynard.
The solution was dubbed "collodion", gluey) by Dr. A.A.
Gould of Boston, Massachusetts.
Wet-plate collodion photography
In 1851, Frederick Scott Archer, an Englishman, discovered that collodion could be used as
an alternative to egg white on glass photographic plates.
Collodion reduced the exposure time necessary for making an image.
This method became known as the 'wet-plate collodion' or 'wet collodion' method.
Collodion was relatively grainless and colorless, and allowed for one of the first high-quality
duplication processes, also known as negatives.
This process also produced two types of positives: the ambrotype; the tintype.
The process required great skill and included the following steps:
Clean the glass plate In the light, pour "salted" collodion onto
the glass plate, tilting it so it reaches each corner.
The excess is poured back into the bottle.
Take the plate into a darkroom or orange tent and immerse the plate in a silver nitrate
sensitising bath Lift the plate out of the bath, drain and
wipe the back, load it into a plate holder and protect from light with a dark slide.
Load the plate holder into the camera, withdraw the dark slide and expose the plate
Develop the plate Fix the plate
All of this was done in a matter of minutes, and some of the steps in safelight conditions,
which meant that the photographer had to carry the chemicals and a portable darkroom with
him wherever he went.
After these steps the plate needed rinsing in fresh water.
Finally, the plate was dried and varnished using a varnish made from sandarac, alcohol
and lavender oil.
Dark tents to be used outdoors consisted of a small tent that was tied around the photographer's
waist.
Otherwise a wheelbarrow or a horse and covered wagon were used.
Dry collodion plates Richard Hill Norris, a doctor of medicine
and professor of physiology at Queen's College, Birmingham, is generally credited with the
first development of dry collodion plate in the 1860s.
In 1894 he took out a new patent for dry plate used in photography.
Medical Many wart-remover preparations consist of
acetic acid and salicylic acid in an acetone collodion base used in the treatment of warts
by keratolysis.
Nitrocellulose solution is also used presently in 'MedTech's NewSkin' liquid bandage product.
Other uses Collodion is widely used to glue electrodes
to the head for electro-encephalography.
Non-flexible collodion is used in theatrical makeup for various effects.
When applied to the skin, it shrinks as the solvent evaporates, causing wrinkles and is
used to simulate old age, or scars.
Collodion is used in the cleaning of optics such as telescope mirrors.
The collodion is applied to the surface of the optic, usually in two or more layers.
Sometimes a piece of thin cloth is applied between the layers, to hold the collodion
together for easy removal.
After the collodion dries and forms a solid sheet covering the optic, it is carefully
peeled away taking contamination with it.
Collodion is a pure type of pyroxylin used to embed specimens which will be examined
under a microscope.
While in Paris René Dagron became familiar with the collodion wet plate and collodion-albumen
dry plate processes which he would later adapt to his microfilm and Stanhope production techniques.
Collodion was used by Alfred Nobel in his development of blasting gelatin, a more powerful,
flexible, and water resistant variation on his highly successful product, Dynamite.
Some types of nail polish also contain collodion.
See also Collodion baby
References
External links
WATCH: George Eastman House "The Collodion – Photographic Processes"
The Getty Museum: The Wet Collodion Process Step by Step Wet Plate Photography
Making a Photograph During the Brady Era John Coffer
Collodion Collodion: Material Safety Data Sheet
Compound W data sheet Civil War Reenactors Photography Forum
Getting started in Wet Plate Collodion Photography Origins and the process of creating a collodion
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