239
CALOTYPE AND TALBOTYPE
On February 8, 1841, William Henry Fox Talbot (1800–
1877) patented a paper negative process he christened
the calotype. The process revolutionized photography
by introducing two substantive improvements: it greatly
reduced exposure length, in some cases by a factor
of more then one hundred, and secondly, it yielded a
chemically robust negative capable of enduring repeated
contact printing for positive copies.
The evolution of photography until this moment had
been signifi cant but rudimentary. Thomas Wedgwood
(1771–1805) in 1802 was the fi rst to conceptualize and
create images with photosensitive silver salts. But no
one, including Wedgwood, had cracked the code for fi xa-
tion: captured images inevitably faded from the presence
of chemically reactive compounds in the paper. By 1839,
two novel photographic systems on paper demonstrated
signifi cant gains in photochemical stability. The fi rst was
Talbot’s photogenic drawing, the second by Hippolyte
Bayard (1801–1887), was the lesser-known direct paper
positive. But both required lengthy exposures, yielded
delicately delineated images and were subject to fading
despite their improved durability. The daguerreotype
was a third process known at this time; it produced a
clear and bright silver amalgam image on a silver plate
and its mirror-like detail captured the imagination of
everyone who saw one. Like the direct paper positive,
it produced a unique object.
The fl edgling photogenic drawing process was hailed
by many but was also heavily criticized, especially
when compared to the extraordinary images rendered
by the daguerreotype. Talbot had also not been fully
satisfi ed with the photogenic drawing and he continued
his research. On September 20, 1840, while searching
for ways to increase its sensitively, he made a pivotal
discovery.
I had been trying pieces of sensitive paper, prepared in
different ways, in the camera obscura, allowing them to
remain there only for a very short time, with a view of
fi nding out which was the most sensitive. One of these
papers was taken out and examined by candlelight. There
was little or nothing to be seen upon it, and I left it lying
on a table in a dark room. Returning some time after I took
up the paper, and was very much surprised to see upon
it a distinct picture. I was certain that there was nothing
of the kind when I had looked at it before, and, therefore
(magic apart), the only conclusion that could be drawn
was that the picture had unexpectedly developed itself
by a spontaneous action. (Literary Gazette)
Talbot immediately retraced his steps and realized
that papers given only a brief exposure to light could
be further developed with gallic acid. Sir John Herschel
and the Reverend John B. Reade were also aware of
the ability of gallic acid to act as developing agent (see
Schaaf 1992 and Wood, 1980 for a thorough description
of these historic events). Until this time, the presence
of the latent image was not known and the sun acted as
the developing agent. Images were created by placing
a fl at, thin object (such as a piece of lace or botanical
specimen) in close contact with a sensitized sheet of pa-
per and exposing directly to sunlight. A photochemical
reaction occurs in the sensitized sheet and the portions
unprotected by the specimen turn rich, purple and red
toned hues. The longer the exposure, the darker the im-
age, but achieving this richness could take an hour or
more. This is called the printing-out process, and is the
basis of photogenic drawings, salted paper prints, and
many other photographic processes. These processes,
were, however, used primarily to create positive images,
and at the time were called “transfers” or “copies.”
The word “calotype” originates from the Greek kalos
and typus meaning “beautiful image.” In the 20th cen-
tury, it came to be used as a general term for positive
prints from paper negatives, but it is recommended that
the meaning remain faithful to Talbot’s original defi ni-
tion, that of a paper negative. The calotype was never
used to directly make positive prints, largely because the
image tonality did not yield the beautiful colors offered
by the printing-out process. Shortly after its creation,
another term for calotype, “Talbotype,” was promoted
by many of the inventor’s supporters. It appears in the
literature, patents and Talbot’s commercial printing and
publishing establishments in Reading and London. Be-
cause many photographers modifi ed Talbot’s formula to
suit their individual needs, the term calotype specifi cally
refers only to Talbot’s patent process. The many other
paper processes, whether developments from Talbot’s
process, or from (sometimes serendipitous) discoveries
made while trying to improve it, are not calotypes. The
distinctions between ‘calotype,’ ‘plain paper,’ ‘waxed
paper,’ et cetera were clearly understood in Victorian
time.
The photographic image is created through the light
sensitivity of silver halides, the chemical amplifi ca-
tion of the latent image and the removal of unexposed
silver halides from the paper with a fi xing agent. The
fi nal image silver is attached to the paper fi bers, liter-
ally imbedded within their matrix. The fi ve essential
components of the paper negative process are the paper
substrate, sensitizing chemistry, developer, fi xer and
post processing alterations. Each of these components
is applied and combined by hand and thus subject to
any number of subtle variations that alter its physical
character. The fi nal result is a sheet of high quality paper
with a neutral gray image in reversed values: highlights
in the original subject appear as dark image areas, while
the shadows of the subject appear in increasingly lighter
tones on the paper, the deepest shadows translate as pure
paper. For example, if the image captured was a bright
outdoor scene, the negative will appear very dark over-