241
graphs. As sited by Ware (1994), there should be distinct
yellow high values indicative of the presence of silver
iodide after potassium bromide fi xation. This striking
characteristic is present in the negatives held in the
National Portrait Gallery of Scotland by the Scottish
team, Robert Adamson (1821–1848) and David Octa-
vius Hill (1802–1870) who produced an outstanding
body of work.
With impressive raw talent and skill in the arts and
sciences, the fi rst photographers brought a wealth of
materials, technical expertise and fi nesse to the new art
form. Nowhere is this more evident than in the post-
processing treatment and preparation for printing. Nega-
tives could be altered for printing in a number of ways:
retouching, masking, trimming, inscribing, use of tabs
for handling and wafers for affi xing sheets for printing,
coating, re-fi xing or chemical intensifi cation.
One of the most dramatic modifi cations to the paper
negative was saturating the paper with wax, resin or oil,
rendering the substrate more translucent. When viewed
under normal illumination, the paper can appear waxy,
shiny with yellow or orange tones overall. Creases ap-
pear as opaque lines and the paper itself may feel heavier.
When the same negative is viewed through transmitted
light, however, the highlights blossom, causing details
to appear crisp and clear. Beeswax was a familiar and
well-known material to 19th-century artists and was the
primary material for waxing paper negatives. Numerous
methods existed for preparing waxed tracing papers
such as sprinkling grated wax onto paper and warming
with an iron or immersing the paper in a shallow tub of
molten wax. Excess wax could be removed by placing
the paper between blotters and warming with an iron.
Experiments using oils, gums and resins were also re-
ported in the photographic literature, although the rare
examples in extant collections of negatives suggest their
use was not widespread.
The narrow range of latitude and strong contrasts of
paper negatives could be reduced or enhanced by waxing
which enhanced the translucency and shortened print-
ing time by applying media such as graphite powder or
pigmented washes, by ironing the paper or by selective
coating portions of the image with additional transpar-
entizing agents. Similarly, fl aws were retouched and
image details could be outlined with these same materi-
als. Many photographers inscribed their negatives with
information, ranging from dates or numbers, to extensive
descriptive text. Perhaps the ultimate modifi cation was
post processing chemical treatment by refi xing or im-
age intensifi cation and is an example of how close dark
room procedures of the 19th century are to those of silver
halide photography in the 21st century.
Each formulation described above was subject to
adaptation by devotees, and often the variant was identi-
fi ed by name as a separate method, such as “plain paper
process” or “wet paper process.” In 1856, Sparling
lists six calotype formulas by photographer’s name.
Typically, changes were made by adjusting or adding
chemical constituents, organic components (including
gelatin, albumin, collodion, and sugar), by altering the
temperatures of processing baths, even by exposing
the paper negative while damp. After the introduc-
tion of the waxed paper negative process in 1851 by
Gustave LeGray (1820–1882), a French encyclopedia
(Blanchère, 1865) lists no less then 44 paper negatives
processes, most of which are close variants of either the
calotype or the waxed paper negative process.
Travelling photographers from the West were quick
to exploit the advantages of the paper negative and many
hundreds survive documenting places as far away as
the Holy Land and the Orient. Subjects in all formats
included regional architecture, local people and cos-
tumes, scenes, views, and documentation of scientifi c
specimens. Shorter exposures and assembly of familiar
materials appealed to the early travelling photographers.
The daguerreotype could not compare to the paper
negative’s lightweight ease and fl exibility, especially
in extreme climates. Photographers of the 1850s modi-
fi ed their processes when travelling in hot, arid zones
where unexposed, sensitized negative papers would
easily spoil. A notable example is the aforementioned
“wet paper process” whereby the sheets are iodized
the night before, fully sensitized the next morning and
placed into the negative frame while damp. Exposure
and processing must occur within 24 hours. Each of
the halides (chloride, bromide and iodide) have dif-
ferent reactivity rates, and the sensitizing solution was
adjusted by changing their ratio. After Irishman John
Shaw Smith (1811–1873) traveled in the Middle East
between 1850 and 1852, he read his formulations to the
Dublin Photographic Society,
When the temperatures rose above 85, these papers
would not keep during the day, they became spotted. This
diffi culty I overcame as follows: -an iodizing bath was
prepared similar to the last mentioned, only leaving out
the solid iodine and substituting as follows:- four drops of
‘bromure d’iode’’ were added to the bath, ... the effect of
this addition of the ‘bromure,’ while it nearly doubled the
required time of exposure in the camera, was, to cause
the papers prepared to keep well during the whole day,
under the highest temperatures, the papers being excited
in the morning and developed the same evening.” (Journal
of the Photographic Society, April 21, 1857)
The calotype united photography and the printed
word. Daguerreotypes could never be realistically in-
cluded in multiple book editions, nor could the fragile
photogenic drawing process withstand the rigors of
printing. But many dozens of positive prints could be
produced from a single calotype. The fi rst photographi-
cally illustrated book was the Pencil of Nature, with a