THE PHOTOGRAVURE
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| Karl Klic Inventor of the Talbot-Klic Dust-Grain process |
Intaglio printing: "A printing process that uses an etched or engraved plate; the plate is smeared with ink and wiped clean, then the ink left in the recesses makes the print." (WordNet® 3.0. Princeton University.)
Aquatint: "A technique of etching copper with acid to produce an effect resembling the flat tones of wash or watercolour. The tone or tint is obtained by acid (aqua) biting through the pores of a ground that only partially protects the copper." (Collins English Dictionary)
What it is:
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A Venetian Canal
Stieglitz, Alfred
Picturesque Bits of New York, 1894
10.5 x 7.5 in
Photogravure
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Photogravure is a half-tone intaglio printing process similar to engraving. A copper plate is coated with a light sensitive gelatinized carbon tissue made from a positive transparency, then placed in an etching bath, very similar to the aquatint process. The thickness of the gelatin on the plate determines how deep the etching will be. After being washed, then, like all intaglio processes, the plate is coated with ink and wiped, leaving ink only in the recessed areas of the plate. Paper is placed on the plate and they are run through a press, resulting in a printed image.
The finished product is an image with fine details and a long tonal range. Unlike other photomechanical processes, a photogravure does not consist of a pattern of dots, but rather an irregular arrangement of ink deposited in different amounts, producing the gradations in an apparent continuous tone.
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| Irregular distribution of ink, and detail of tonal gradation. |
A brief history:
The photogravure was a product of the long pursuit of a permanent and mass producible photograph. The process as it is known today was patented by painter Karl Klic in 1879, and it is based upon the early engraving experiments of Joseph-Nicephore Niepce and William Henry Fox Talbot. Klic's method, known as the Talbot-Klic Dust-Grain gravure, was unique in that before the resist was transferred to the plate, an acid-resisting gum in dust form was applied to the surface, which allowed the gelatin to remain in place during the carbon process. This carbon process could not be used previously because the resist would fall off the plate when drying. Because of the unprecedented reproduction accuracy of photogravure, it was widely accepted and used largely to print high quality book illustrations. Photographers and artists also were attracted to its high quality prints, and they used it as a print medium for their own works.
Peter Henry Emerson's Marsh Leaves (1895) is regarded as perhaps some of the finest examples of photogravures in a printed book.
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A Winter's Sunrise
Emerson, Peter Henry
Marsh Leaves, 1890
6.9 x 12.8 cm
Photogravure
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The first prominent publication of the 20th century to feature photogravure was the periodical Camera Work (1903-1917) by Alfred Stieglitz, which published a total of 416 copperplate illustrations during its run.
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The Terminal
Stieglitz, Alfred
Camera Work XXXVI, 1892
12.1 x 15.9 cm
Photogravure
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Step by step:
A Treatise on Photogravure in Intaglio by the Talbot-Klic Process (1890) is a detailed guide and overview of the photogravure process. It provides in-depth instruction on how to successfully create a print, as done in the 19th century.
- The copper plate is cleaned and coated with an acid resist of resin or bitumen, then heated to bond the resist to the plate.
- A carbon tissue is soaked in potassium bichromate solution, then dried. This causes the gelatin film on the tissue to become light sensitive.
- For the image, a positive transparency is made from a negative. The positive print is then contact printed under ultraviolet light to the sensitized carbon tissue.
- The tissue now is bonded to the plate by being submerged in a cold bath. The plate and tissue are then moved to a warm bath so the tissue can separate from the gelatin. The parts of the gelatin that were exposed the least to light now begin to dissolve in the water, leaving a resist of the image on the plate.
- The plate then goes through a series of etching baths, made from ferric chloride. The bath penetrates the gelatin and the plate, and the depths of the resulting pits depend on the thickness of the gelatin.
- The plate is then washed and is coated with ink. The ink is rubbed into the pits forming the image. Then the plate is wiped evenly, leaving only the recessed areas filled with ink.
- A piece of damp paper is place on top of the plate, and it is run through a press, forcing the image onto the paper. The process can then be repeated if necessary.
Videos demonstrating the process:
Adhering the tissue to the plate: https://www.youtube.com/watch?v=ljT3eyCpIns
Dissolving the gelatin to form the image: https://www.youtube.com/watch?v=xqbhx-vPFy0
Printing from the finished plate: https://www.youtube.com/watch?v=0ZhMhgZwSts
References:
Ritzenthaler, Mary L, Diane Vogt-O'Connor, and Mary L. Ritzenthaler. Photographs: Archival Care and Management. Chicago: Society of American Archivists, 2006.
Morrish, David, and Marlene MacCallum. Copper Plate Photogravure: Demystifying the Process. Amsterdam: Focal Press, 2003.
Hannavy, John. Encyclopedia of Nineteenth-Century Photography. New York: Routledge, 2008.
Denison, Herbert. A Treatise on Photogravure in Intaglio by the Talbot-Klic Process. London: Iliffe, 1890.
Art of the Photogravure (2013).
Image Permanence Institute (2013). Graphics Atlas: Identification.
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