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The Process:
Photogravure (called heliogravure in Europe), blends photographic
and etching processes to produce an original work of art with a
textural richness, luminosity and range of tone not possible with
conventional photographic printing processes. The painstakingly
complex continuous tone process, called aquatint photogravure, dust-grain
photogravure or Talbot-Klic process, works as follow:
A negative image on film is converted in the desired proportions
to a positive film. The positive film is placed in a vacuum contact
frame and exposed by ultra-violet light onto a dichromate-sensitized
gelatin carbon tissue. A fine dust of asphalt powder is laid and
melted onto a highly polished copper plate. The exposed carbon tissue
is then applied onto the grain-dusted plate and dried. The carbon
tissue now adhering to the plate is developed in warm water, leaving
on the plate various thickness of gelatin corresponding to the photographic
information. After conditioning, the plate is etched in three to
four baths of ferric chloride solutions of different concentrations
which penetrate the different thickness of the gelatin accordingly,
thus creating an etch of various depths. After etching, the plate
retouched in traditional engraving techniques, is inked, hand-wiped
and printed like an etching with an intaglio press onto a damped
cotton fiber paper. The print is then dried and cured. The photogravure
process is truly a lost art; the importance of the medium lies in
the way it connects art and science, past and future, the ethereal
and ephemeral qualities of light with the concreteness and permanence
of ink on paper.
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