The Daguerreotype Process
Louis Jacques Mande Daguerre was the man who perfected the method of
producing direct positive images on a silver-coated copper plate and also who
gave his name to the process “Daguerreotype”. The daguerreotype process was the
earliest technique of attaining permanent pictures with a camera. He used to
experiment and tried to fix the images formed by the camera Obscura around
1824. In 1829 he teamed up with Joseph Nicephore Niepce, a French scientist and
inventor, which was the one who had succeeded in securing a picture of the view
from his window by using a camera Obscura and a pewter plate coated with
bitumen. He called this process heliography (“sun drawing”), but although he
had managed to produce a permanent image using the camera Obscura, the exposure
time was around 8 hours, which was too long.
As already stated, the first daguerreotypes used Chevalier lenses that were
slow. As a result, the camera exposure was too long to take portraits for
commercial purposes. In fact, initially the subjects photographs were immobile
objects such as street scenes, still life and architectural studies. In order
to reduce the exposure times, lenses of a larger diameter started being
introduced.
Niepce later abandoned pewter plates and begun to use silver-plated sheets
of copper, which he discovered a light sensitive compound, “silver iodide”
which was formed because of the vapour from iodine reacted with the silver
coating. Niepce died in 1833, after which Daguerre continued to experiment with
copper plates coated with silver iodide to produce direct positive pictures. He
discovered that the undeveloped image on an exposed plate could be developed
with the fumes from warmed mercury. On 19th August, 1839, there was a meeting
in Paris and Daguerretype Process was revealed to the world.
An Early Daguerreotype Portrait Studio (1842)
A. A Daguerreotype studio was
usually set at the top of a building, which had a glass roof to let in light.
B. The person sat down on a chair placed on a raised platform, which could be
rotated to face light. The men’s head is held still by a clamp (x).
The stages of making a daguerreotype portrait
1. An assistant have to polish a
silver-coated copper plate with long buffer till the surface is highly
reflective (y). c. Then the plate is taken to the darkroom, where it is
sensitized with chemicals such as chloride of iodine and chloride of bromine,
etc. 2. The photographer places the plate into a camera which is placed on a
high shelf (z). When the person is ready the photographer removes the camera
cover and he times the required exposure with a watch. [In this illustration,
the operator is using Wolcott's Mirror Camera, which was fitted with a curved
mirror instead of a lens]. 3. The exposed plate is returned to the darkroom
where the photographic image which is on the silver plate is developed with the
fumes from heated mercury (d). Then the image is “fixed” by bathing the plate
in hyposuphate of soda and also it is washed in distilled water (e) and is left
to dry. 4. Finally the finished photo is covered by a sheet of protective glass
and is either
mounted in a decrritive frame or presented in a leather-bound case. It could
also be painted by hand with a dry powdered pigment. The photos in that time
were very small and the customers to appreciate details had to use a magnifying
glass.
The Daguerreotype Process. 2013. The Daguerreotype Process. [ONLINE] Available at: http://www.photohistory-sussex.co.uk/dagprocess.htm. [Accessed 08 April 2013].
Daguerreotype - Wikipedia, the free encyclopedia. 2013. Daguerreotype - Wikipedia, the free encyclopedia. [ONLINE] Available at: http://en.wikipedia.org/wiki/Daguerreotype. [Accessed 08 April 2013].
The Daguerreotype Process. 2013. The Daguerreotype Process. [ONLINE] Available at: http://inventors.about.com/od/dstartinventions/a/Daguerreotype_3.htm. [Accessed 08 April 2013].
