An interesting variation of the process. The process used in
advertising illustration was to make color separation negatives
either in a standard camera with, perhaps a drop down holder, or
in a "one-shot" camera. Of course standard cameras using
sequential exposures were strictly for still life but a one-shot
could be used for general work. There were two makers of one shot
cameras Devin Colorgraph, National Photocolor, and another whose
name I am drawing a blank on. Both supplied matched film and made
the carbon tissue. Autotype tissue, invented by the Lumiere
brothers and made in England was sold by George Murphy in New
York but was considered inferior to the American made material.
The negatives had to be processed with great control. Also,
the carbon tissue was quite temperature sensitive so the labs
processing it had to be thermostatically controlled. There were
two or three labs in New York who specialized in serving the
advertising agencies who used the process. There was at least one
lab in Los Angeles since some of the movie studios used the
process for advertising originals.
While one can consider the process as having a lot of
flexibility another view is that it required great control of
every step.
The prints were used for original artwork for three or four
color half tone reproduction and occasionally for display. The
prints also allowed a good deal of retouching and manipulation.
Carbon tissue can be exposed directly to light but its
extremely slow and does not lend itself to enlargement. The other
method is carbon-bromide. Carbon tissue will be exposed by
holding it in contact with a bromide print. Special printing
paper was offered by the camera manufacturers for this purpose.
Its obvious that this added another layer of necessary control to
the process. Using a black or gray key made color tracking easier
but I think would not have helped where half-tone plates were to
be made. Four color half tone printing has itself a black or gray
key which masks color errors in denser parts of the image and can
also reduce the amount of colored ink required.
Eventually dye transfer prints replaced carbon and
Kodachrome supplanted that although both dye transfer and color
carbon could be made from Kodachrome transparencies by means of
color separation negatives.
I have somewhere in storage a book from about the 1950s with
reprints of color advertising illustration made from the original
printing plates. Its quite easy to tell those made from carbon
from Kodachrome. The carbon ones have a sort of soft pastel look
while Kodachrome was brilliant and quite sharp.
On 4/28/2019 2:06 PM, Howard Efner wrote:
3 or 4 color carbon can be a difficult process since each tissue has its owndickburk@xxxxxxxxxxxxx
contrast curve and exposure requirements. On the other hand, if a stochastic
negative is used (random dots) the only requirement is to determine the
exposure needed for maximum density for each color and then let the pre-process
determine the color balance of the finished print. Basically a halt-tone type
print rather than a continuous tone print.
Howard Efner
73 de KF5RGU
