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.