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Early
Photographic Processes
Photogenic
Drawing
1835-1840s
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Discovery |
Talbot
William
Henry Fox Talbot was
born in Dorset in 1800. He was a quiet, shy man, a botanist, linguist,
mathematician and inventor. His mother, Lady Elizabeth Fielding,
was an artist.
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1834
Talbot honeymooned at Lake Como in Italy in
1834 with his wife, Constance. There, he attempted to sketch using
a camera lucida - an instrument that transferred the view
before him onto paper.
But he became frustrated with his sketches and determined, with
his knowledge of chemistry, that on his return to England he would find
a way to permanently capture the his image on paper.
He began experimenting
with silver nitrate in 1834.
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1835-38
Experimenting began in the mid-1830s. Talbot's success increased
over subsequent years as he refined his his photogenic drawing
process. He discovered that it worked best if repeated coats of
salt and silver nitrate were given to the paper, and if the paper was
exposed before the coating dried.
Exposure times required were typically an hour or
longer, so the process was not suitable for taking portraits.
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1839
Talbot
made no formal announcement of his discoveries until he heard that on 7
January 1839, an announcement had been made in Paris that LJM Daguerre
had discovered a way of fixing a photographic image.
Talbot
reacted immediately and wrote a paper on his process that was presented
to the Royal Institution, in London, on 31 January 1839 by Michael
Farraday. In fact Daguerre's
discovery was quite different from Talbot's
Talbot later invented and patented his
Tablotype
or Calotype
process. This
negative/positive process, was the forerunner to today's conventional
photography.
Both the photogenic
drawing process and the subsequent calotype process enabled multiple
prints to be produced from a single negative.
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Process |
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Soak writing paper in a weak solution of sodium chloride (common
salt).
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When dry, sensitise the paper by brushing one side with a strong silver nitrate solution.
This causes silver chloride to be formed on the surface of the paper.
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Take the photo while the paper is still wet. An exposure of at
least an hour may be needed. This will imprint an image on the
paper.
- Remove the paper from the camera and wash it.
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stabilise (or 'fix') the image on the paper by soaking the paper in a
strong solution of sodium chloride.
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This produces a negative image on paper.
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Treat a second sheet of paper with salt + silver nitrate, as above.
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Lay the negative created above on top of the newly-coated sheet of paper
+ expose to light.
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Wait for a positive image to emerge then fix as above. |
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Result |
A
salt print retains its original brown colour for only a few hours, then
turns purple.
Talbot also experimented
with other solutions to stabilise his images. Images stabilised
with potassium iodide are often yellow, and those stabilised with
potassium bromide, purple.
Much
of Talbot's early experimenting was done with without the use of a
camera - Talbot laying leaves, lace and other items under a sheet of
glass placed on top of his coated paper.
The first photograph taken by
Talbot using a camera was in August 1835. The subject was his
lattice window at Lacock Abbey.
Talbot's
early cameras produced very small images, less than
1.5 ins. square. His early cameras were small simple wooden boxes
with a lens. On one occasion, his wife described them as his
mousetraps.
The real benefit of Talbot's
work came when he announced his Calotype
process in 1841.
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In
Edinburgh
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From
1831 onwards, Talbot had corresponded with a scientific friend in
Scotland.
This
was Sir David Brewster
who
had many links who played an important part in the development of
photography in Edinburgh, and became President of the Photogrpahic
Society of Scotland, which met in Edinburgh from 1856 onwards. |