coop@rdin.UUCP (Robert Cooper) (10/04/85)
I've always been fascinated by the development of different
technologies. As I watch the current computer environment change
(e.g., 8 bit to 32 bit, Unix and PC Dos, no res to low res to high res
graphics, etc.) I like to study the changes that were made in early
19th century photographic technology to look for similarity between
how the current computer technology is developing and how photographic
technology developed. For example, what will be the future of new
programming languages? Why and how will this new language become
popular? Who can say? If we look at photography's development, we
might have a better understanding of the process. The most popular
photographic system in use today (for the most part) is a
negative/positive process, yet for the first 20-25 years of
photography, the most popular process was a direct positive system
(i.e., no negative is created). Why that change happened is an
interesting story and there just might be a lesson to be learned from
it.
In 1839, the world was amazed to learn that the age-old problem of
capturing an image on a prepared surface was solved by not one but two
different methods. The public was fascinated by the implications and
possible uses of this new science. What were these two competing
methods and why did one become so popular so quickly? The first
method to be announced was in Paris, by Louis Daguerre. His method was
to use a silver-coated metal plate, sensitized with iodine fumes.
After exposing a prepared plate to light, he developed the plate with
its latent image with fumes of mercury to reveal a unique positive
image. In England, Henry Fox Talbot, upon hearing of Daguerre's
discovery, rushed to announce the results of his work of the past
couple of years. He had discovered that by soaking fine writing paper
in sodium chloride and then silver nitrate, exposing the treated paper
to light, and then processing the paper in pyrogallic acid, a negative
image was created, which could then be used to print on a second sheet
of similarly-treated paper to get a positive image. Both methods
benefited from the intense public interest, especially with suggested
improvement to their processes. The most important of these was the
use of hyposulfite of soda to help fix the images.
Like everything else, Daguerre's Daguerreotype and Talbot's Calotype
had their strong points and weak points. The Daguerreotype's strongest
feature was its almost unbelievably strong, sharp, detailed image. In
fact, there aren't many films available today that have a finer grain
structure. The Calotype's image was much softer, due to the light
diffusing fibers in the paper negative. The Calotype's strongest
feature was its separate negative which allowed for unlimited positive
copies. A Daguerreotype is a unique image. If you wanted a second
copy, you had to take another Daguerreotype of it. The Daguerreotype's
image was very easily damaged, so it had to be protected by a glass
cover in a miniature case or frame. The Daguerreotype also had a
higher material cost, its silver-coated plate being expensive to
manufacture. The Calotype, being a paper product, didn't have these
limitations. Since it seems the two methods are fairly evenly matched,
why was one method almost universally practiced from 1839 to 1860
while the other remained in the background till about 1860 when it
finally developed into the major photographic product?
If I were to pick any one reason, I would say it was 'marketing' that
guaranteed the almost 20-year popularity of the Daguerreotype over the
negative/positive processes. Fox Talbot believed he was entitled to
earning from his invention, and he secured patent protection and
started selling licenses in England, France and America. During the
1840's he and his licensees sought to popularize the basic process
under the name Talbotype and fought to maintain patent control of the
negative-positive with lengthy court proceedings. Daguerre, on the
other hand, went a different route. After discussion with the French
Academy of Science, he gave his process free to the world, after being
assured of a life pension from the French government. Within weeks of
the announcement, Daguerreotypes were being made in all the capitals
in Europe and in America. A new industry and art form had been born.
In another posting, I hope to explore the reasons the
negative/positive process finally overtook the direct positive
process.
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Robert Cooper Resource Dynamics Inc.
{philabs|delftcc}!rdin!coop 150 East 58th Street
New York, NY 10155
(212) 486-9150