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Talbot claimed that he produced camera pictures in ten
minutes “during the brilliant summer of 1835.” On the
other hand, his notebook of 14 August 1839 records
“... a picture made by the camera in an hour, on a dark
day.” Exposure times of both processes were reduced,
particularly by improvements in the chemistry of the
sensitive materials. In 1840 John Goddard in England
found that Bromine vapour increased the sensitivity of
daguerreotype plates. The same year Talbot discovered
that gallic acid added to silver nitrate produced a latent
image after a brief exposure, which became visible on
development. The consequences were dramatic. With
exposure times reduced to a few minutes, the exciting
prospect of photographing living people became reality.
By the end of 1840 it became evident that commercial
portrait photography could be achieved using either pro-
cess and the fi rst studios opened a year later. However,
exposure times still limited the photographer’s craft.
The streets of Talbot’s London calotypes (c 1845) are
peopled by ghosts or eerily empty because the expo-
sures of two or three minutes were too long to capture
the city bustle.
In 1851 Frederick Scott Archer introduced the wet
collodion process, an innovation which combined some
of the best elements of the pioneer processes and re-
duced exposure times to a few seconds. Wet collodion
soon superseded both earlier processes and promoted an
explosion of popular interest in photography. A wider
range of subjects became possible, yet the length of
exposure still imposed limitations. Victorian portraits
usually show solemn faced sitters because it was dif-
fi cult for them to smile naturally for several seconds.
Action shots remained problematic, most movement
being recorded as a blur. Thus, Roger Fenton’s Crimean
War photographs (1855) often have the appearance
of empty stage sets. Tripods were essential to keep
the camera steady and exposure technique remained
primitive, involving removing the lens cap for a period
measured by counting or timing with a watch. Pho-
tographers made life more diffi cult for themselves by
failing to deal systematically with the known factors
that affected exposure. The attitude of William Lake
Price in his Manual of Photographic Manipulation
(second edition 1868) was typical. “No fi xed data can
be given for duration of exposure,... Still, by practice,
a sort of instinct grows on the photographer,...” Using
specialised apparatus and techniques, photographers
such as Thomas Skaife, Thomas Sutton and George
Washington Wilson, did manage to reduce exposure
times to fractions of a second and capture small but sharp
images of moving subjects. Lenses of large aperture
and short focal length were essential, as was ideal light
and careful processing. Even so, as William England
recorded in The Photographic News (April 11, 1862), to
produce these so-called `instantaneous’ photographs “avery large amount of patience is necessary, and failures
are very plentiful.”
All this fi nally changed in the 1870s with the intro-
duction of the fast gelatine halide dry plates that readily
allowed exposures of fractions of a second. The techno-
logical spin-off was enormous. Shutters became an es-
sential adjunct to the camera, which themselves became
smaller and could be held in the hand. Exposure meters
fi rst began to be widely marketed in the late 1880s. The
development of new artifi cial light sources was stimu-
lated. Roll fi lm became practicable and with it moving
pictures and the cinema. At last, photography in a wide
range of situations, night or day, was simplifi ed, action
could be recorded and John Herschel’s 1860 dream of
‘snapshot’ photography became a reality.
Suddenly a new world was opened to photographers.
New insights into the natural world were provided by
the motion studies of Muybridge and Marey. Unposed
pictures taken without the subject’s knowledge became
possible for almost the fi rst time and Paul Martin’s
street life photographs of the 1890s are a landmark
of the period. The rapid growth of a new amateur
market and the loosening of photography’s ties with
the graphic arts brought a fresh stimulus to the debate
about photography’s role as an art form. One of the most
infl uential photographers to exploit the new technology,
P.H. Emerson, wrote passionately on the debate in his
book, Naturalistic Photography (1889).
The widespread introduction of the gelatine dry plate
and its consequences marks the beginning of modern
photography. During the twentieth century, steady im-
provements in equipment and sensitive materials con-
tributed to further small reductions in exposure times.
Nevertheless, improvements in the twentieth century
were small and incremental compared to the great strides
made at the end of the nineteenth. Determining optimum
exposure times continues to be a key factor in making
good photographs today but current practice and style
is largely made possible by technological developments
made a century earlier.
John WardSee also: Niépce, Joseph Nicéphore; Daguerreotype;
Daguerre, Louis-Jacques-Mandé; Talbot, William
Henry Fox; Latent Image; Calotype and Talbotype;
Archer, Frederick Scott; Wet Collodion Negative; Wet
Collodion Positive Processes; Fenton, Roger; Price,
William Lake; Skaife, Thomas; Sutton, Thomas;
Wilson, George Washington; England, William;
Camera Accessories (Shutters, Tripods, Plate-Holders
etc.); Actinometers and Exposure Measurement;
Herschel, Sir John Frederick William; Muybridge,
Eadweard James (Edward Muggeridge); Marey,
Etienne Jules; Martin, Paul Augustus; and Emerson,
Peter Henry.EXPOSURE
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