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Lyte barely practicable. More useful was the collo-
dio-albumen process published in 1855 by the French
scientist, J.M.Taupenot. The process involved washing
wet collodion plates in a silver nitrate bath. After coat-
ing with a protective layer of albumen, the dried plates
could be stored. Another silver bath a few hours before
they were needed sensitised the plates and after drying
they were ready for use. Taupenot’s process formed the
basis of several similar processes. Particularly popular
in England were those by Thomas Fothergill and Joseph
Sidebotham. In 1856 Richard Hill Norris patented a pro-
cess where a collodion plate was coated with gelatine or
gum arabic to preserve its sensitivity. Norris dry plates
were introduced commercially and sold widely. Another
popular dry collodion technique was the tannin process
introduced by Major C. Russell in 1861. The sensitised
collodion plate was washed before applying a tannin
solution and drying. It was much favoured by English
amateurs because it was simple and reliable. In 1864
W.E. Bolton and E.J. Sayce announced an important
development, a process which involved mixing silver
bromide into collodion forming an emulsion. This was
the fi rst practicable photographic emulsion.
With the processes described above, dry sensitised
plates could be produced which were relatively stable
and in the case of collodio-bromide emulsions had a
degree of consistency and reliability. It is also clear that
negatives could be made that matched the best made
from wet collodion. But what publications of the period
do show is that for most photographers, dry collodion
plates could not match the speed of wet plates. Using
collodio-albumen, one popular handbook suggested
exposures “about double the time required for wet
collodion negatives” (Cox 1857, 26). A Photographic
News contributor similarly reported “experience has
shown me that dry collodion is two or three times less
sensitive than the wet collodion;” (Collard 1858, 75).
Comparative tests by the Manchester Photographic
Society in 1858 confi rmed these views. The Taupenot
process was considered “the best dry process yet discov-
ered...” but it pronounced that “The exposure required
is moderate; pictures may be taken with an exposure
of 15 seconds and upwards.” Fothergill’s variation was
considered inferior and the Hill Norris gelatine process
was said to require exposures “at least double that
of the collodio-albumen (Photographic News, 1858,
117). Russell’s Tannin Process, if anything, normally
required longer exposures. Sutton claimed “about four
minutes for a sun-lighted view...” (Sutton, 1862, 88),
while H.C. Jennings suggested three minutes (Jennings,
1863, 577). Contemporary commentators also agreed
that while the Bolton and Sayce emulsion plates kept
particularly well, they were slower than wet collodion.
Jerome Harrison suggested 15 seconds as the average
exposure (Harrison 1888, 127).


A few photographers however, claimed results with
dry plates that matched the so-called `instantaneous
photographs,’ made by the likes of George Washington
Wilson and Valentine Blanchard using wet collodion.
In 1862 Sutton published details of a `rapid dry pro-
cess’ based on the tannin process, which he claimed
“had been known to Dr. Hill Norris for upwards of two
years” (Sutton 1862, 106). There seems little doubt
that `instantaneous’ pictures were obtained using dry
collodion processes but short exposures with dry col-
lodion probably required considerable skill and a great
deal of luck. A Photographic News review of a Sutton
pamphlet confi rms seeing “excellent pictures with very
rapid exposures” but also writes of “utter and disgust-
ing failures.” It bemoaned the fact that the majority of
photographers failed and groped towards explanations
(1864, 266). Part of the answer was that too many dry
processes incorporated the impure kitchen consumables
alluded to by Werge. They were added as preservatives
or sensitisers but their chemical composition was wildly
variable and their action imperfectly understood.
The American, Carey Lea, rightly observed “it is not
random experimenting that does good—not publishing
that a few plates have been obtained by this or that
preservative. Useful experimenting must be systematic
and comparative” (Carey Lea, 1868, 504). At the end
of the 1860s, most dry plate practitioners were ama-
teurs while their professional colleagues relied almost
entirely on wet collodion. More than a decade was to
pass before all photographers began using the same
sensitive materials.
John Ward

See also: Bolton and Sayce; Harrison, Jerome; Lea,
Cary; Lyte, Maxwell; Niépce de Saint-Victor, Claude
Félix Abel; Shadbolt, George; Sidebotham, Joseph;
Sutton, Thomas; and Werge, John.

Further Reading
Abney, W. de W., Emulsion Processes in Photography, London:
Piper & Carter, 1878.
Anonymous Report, “Manchester Photographic Society—Annual
General Meeting, 1858.”
The Photographic News, Nov., 12, 1858, 117–118.
Anonymous Review, “Instantaneous Dry Collodion Processes
by Thomas Sutton,” The Photographic News, June 3, 1864,
266–269.
Collard, M, “On Dry Collodion,” The Photographic News, Oct.
22, 1858, 75–76.
Cox, Frederick, The Photographic Tourist, London: Frederick
Cox, 1857.
Draffi n, John, “Comparative Experiments on some of the Dry Pro-
cesses,” The Photographic News, May 13, 1859, 109–111.
Eder, Josef Maria, (Trans. Epstean), History of Photography
(Dover ed.), New York: Dover Publications Inc., 1978.
Gernsheim, Helmut & Alison, The History of Photography,
London: Thames & Hudson, 1969.

DRY PLATE NEGATIVES: NON-GELATINE

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