Photogravure
Encyclopedia
Photogravure is an intaglio
Intaglio (printmaking)
Intaglio is a family of printmaking techniques in which the image is incised into a surface, known as the matrix or plate, and the incised line or area holds the ink. Normally, copper or zinc plates are used as a surface, and the incisions are created by etching, engraving, drypoint, aquatint or...

 printmaking
Printmaking
Printmaking is the process of making artworks by printing, normally on paper. Printmaking normally covers only the process of creating prints with an element of originality, rather than just being a photographic reproduction of a painting. Except in the case of monotyping, the process is capable...

 or photo-mechanical process whereby a copper plate is coated with a light-sensitive gelatin tissue which had been exposed to a film positive, and then etched, resulting in a high quality intaglio print that can reproduce the detail and continuous tones of a photograph.

History

The earliest forms of photogravure were developed in the 1830s by the original pioneers of photography itself, Henry Fox Talbot in England and Nicéphore Niépce
Nicéphore Niépce
Nicéphore Niépce March 7, 1765 – July 5, 1833) was a French inventor, most noted as one of the inventors of photography and a pioneer in the field.He is most noted for producing the world's first known photograph in 1825...

 in France. They were seeking a means to make prints that would not fade, by creating photographic images on plates that could then be etched. The etched plates could then be printed using a traditional printing press. These early images were among the first photograph
Photograph
A photograph is an image created by light falling on a light-sensitive surface, usually photographic film or an electronic imager such as a CCD or a CMOS chip. Most photographs are created using a camera, which uses a lens to focus the scene's visible wavelengths of light into a reproduction of...

s, pre-dating daguerreotype
Daguerreotype
The daguerreotype was the first commercially successful photographic process. The image is a direct positive made in the camera on a silvered copper plate....

s and the later wet-collodion photographic processes. Fox Talbot worked on extending the process in the 1850s and patented it in 1852 ('photographic engraving') and 1858 ('photoglyphic engraving').

Photogravure in its mature form was developed in 1878 by Czech painter Karel Klíč
Karel Klíc
Karel Václav Klíč was a Czech painter, photographer and illustrator. He appears to be known as one of the inventors of photogravure ....

, who built on Talbot's research. This process, the one still in use today, is called the Talbot-Klič process.
Because of its high quality and richness, photogravure was used for both original fine art
Fine art
Fine art or the fine arts encompass art forms developed primarily for aesthetics and/or concept rather than practical application. Art is often a synonym for fine art, as employed in the term "art gallery"....

 prints and for photo-reproduction of works from other media such as paintings. Photogravure is distinguished from rotogravure
Rotogravure
Rotogravure is a type of intaglio printing process; that is, it involves engraving the image onto an image carrier...

 in that photogravure uses a flat copper plate etched rather deeply and printed by hand, while in rotogravure, as the name implies, a rotary cylinder is only lightly etched, and it is a factory printing process for newspaper
Newspaper
A newspaper is a scheduled publication containing news of current events, informative articles, diverse features and advertising. It usually is printed on relatively inexpensive, low-grade paper such as newsprint. By 2007, there were 6580 daily newspapers in the world selling 395 million copies a...

s, magazine
Magazine
Magazines, periodicals, glossies or serials are publications, generally published on a regular schedule, containing a variety of articles. They are generally financed by advertising, by a purchase price, by pre-paid magazine subscriptions, or all three...

s, and packaging. In France the correct term for photogravure is héliogravure, while the French term photogravure refers to any photo-based etching technique.

Qualities

Photogravure registers a wide variety of tones, through the transfer of etching ink from an etched copper plate to special dampened paper run through an etching press. The unique tonal range comes from photogravure's variable depth of etch, that is, the shadows are etched many times deeper than the highlights. Unlike half-tone processes which merely vary the size of dots, the actual quantity and depth of ink wells are varied in a photogravure plate and are often blended into a smooth tone by the printing process. Photogravure practitioners such as Peter Henry Emerson
Peter Henry Emerson
Peter Henry Emerson was a British writer and photographer. His photographs are early examples of promoting photography as an art form...

 and others brought the art to a high standard in the late 19th century. This continued with the work of Alfred Stieglitz
Alfred Stieglitz
Alfred Stieglitz was an American photographer and modern art promoter who was instrumental over his fifty-year career in making photography an accepted art form...

 in the early 20th century, especially in relation to his publication Camera Work
Camera Work
Camera Work was a quarterly photographic journal published by Alfred Stieglitz from 1903 to 1917. It is known for its many high-quality photogravures by some of the most important photographers in the world and its editorial purpose to establish photography as a fine art...

. This publication also featured the photogravures of Alvin Langdon Coburn
Alvin Langdon Coburn
Alvin Langdon Coburn was an early 20th century photographer who became a key figure in the development of American pictorialism...

 who was a fine gravure printer and envisioned his photographic work as gravures rather than other photo-based processes. The speed and convenience of silver-gelatin photography eventually displaced photogravure which fell into disuse after the Edward S. Curtis
Edward S. Curtis
Edward Sheriff Curtis was a photographer of the American West and of Native American peoples.-Early life:...

 gravures in the 1920s. One of the last major portfolios of fine art photogravures was Paul Strand
Paul Strand
Paul Strand was an American photographer and filmmaker who, along with fellow modernist photographers like Alfred Stieglitz and Edward Weston, helped establish photography as an art form in the 20th century...

's Photographs from Mexico from 1940, reissued as The Mexican Portfolio in 1967 by DeCapo Press. Many years later, photogravure has experienced a revival in the hands of Aperture and Jon Goodman, who studied it in Europe. Photogravure is now actively practiced in only several dozen workshops around the world.

Technique

Photogravure plates go through several distinct stages.
  • First, a continuous tone film positive is made from the original photographic negative. A smaller negative can be enlarged onto a sheet of film, which is then processed to a range of continuous tones with specific densities.
  • The second stage is to sensitize a sheet of pigmented gelatin tissue by immersion into a 3.5% solution of potassium dichromate for 3 minutes. Once dried against a Plexiglas (Perspex) surface, it is ready for the next stage.
  • The third stage (usually the next day) is to expose the film positive to the sensitized gravure tissue. The positive is placed on top of the sensitized sheet of pigmented gelatin tissue. The sandwich is then exposed to ultraviolet
    Ultraviolet
    Ultraviolet light is electromagnetic radiation with a wavelength shorter than that of visible light, but longer than X-rays, in the range 10 nm to 400 nm, and energies from 3 eV to 124 eV...

     (UV) light. A separate exposure to a very fine stochastic or hard-dot mezzotint screen is made, or alternatively an aquatint grain of asphaltum or rosin is applied and fused to the copperplate usually before the exposed gelatin tissue is adhered to the plate. The UV light travels through the positive and screen (if used) in succession, each time hardening the gelatin in proportion to the degree of light exposed to it.
  • The fourth stage is to adhere the exposed tissue to the copper plate. The gelatin tissue is adhered or "laid down" onto the highly polished copper plate under a layer of cool water. It is squeezed into place and the excess water is wiped clear.
  • Once adhered, the fifth stage is to use a hot water bath to remove the paper backing and to wash away the softer, unexposed gelatin. The remaining depth of hardened gelatin is relative to the exposure. This layer of hardened gelatin forms a contoured resist on the copper plate. The resist is dried, and the edges and back of the copper are stopped out (staged).
  • The sixth stage is to etch the plate in a series of ferric chloride baths, from the densest to slightly more dilute, in steps. The density of these baths is measured in degrees Baumé
    Baumé scale
    The Baumé scale is a pair of hydrometer scales developed by French pharmacist Antoine Baumé in 1768 to measure density of various liquids. The unit of the Baumé scale has been notated variously as degrees Baumé, B°, Bé° and simply Baumé . One scale measures the density of liquids heavier than water...

    . The ferric chloride migrates through the gelatin, etching the shadows and blacks under the thinnest areas first. The etching progresses through the tonal scale from dark to light as the plate is moved to successively more dilute baths of ferric chloride. The image is etched onto the copperplate by the ferric chloride, creating a gravure plate with tiny "wells" of varying depth to hold ink. The pattern formed by the aquatint grain or the screen exposure creates minute "lands" around which the etching occurs, giving the copperplate the tooth to hold ink. The "wells" which hold the ink vary in depth, a unique aspect of photogravure.
  • The final stage is to print the cleaned plate.


Printing the plate

Printing a photogravure is similar to printing any other intaglio
Intaglio (printmaking)
Intaglio is a family of printmaking techniques in which the image is incised into a surface, known as the matrix or plate, and the incised line or area holds the ink. Normally, copper or zinc plates are used as a surface, and the incisions are created by etching, engraving, drypoint, aquatint or...

 plate, especially a finely etched aquatint
Aquatint
Aquatint is an intaglio printmaking technique, a variant of etching.Intaglio printmaking makes marks on the matrix that are capable of holding ink. The inked plate is passed through a printing press together with a sheet of paper, resulting in a transfer of the ink to the paper...

. A stiff, oily intaglio printing ink is applied to the whole surface of the plate with a rubber brayer, or a small, stiff squeegee, or a rolled tamper. The plate is then gently wiped with tarlatans to remove the excess ink and drive it into the recesses (wells). It is finally wiped with the fatty part of the palm of the hand in quick glancing strokes. This removes all remaining ink from the polished highlights and high points and leaves ink only in the etched recesses. After the edges are cleaned, the plate is placed on the printing bed of an intaglio press. It is covered with a sheet of dampened rag paper and then two to three layers of thin wool blankets. It is then run through the press at high pressure. The high pressure pushes the fibers of the dampened paper into the wells of the plate which then transfers the ink onto the paper thereby creating the impression. The paper is carefully peeled off the plate and placed between blotters and weighted so it will dry flat. The plate can now be re-inked for another impression or it can be cleaned for storage.

Macdermid Autotype, the last manufacturer of the gelatin pigment paper (tissue) needed to make traditional copper plate photogravure, announced the end of their production in August 2009. Since then, other manufacturers, including Bostick & Sullivan, Phoenix Gravure, and others in India, Taiwan, and Japan have begun supplying gelatin pigment paper (resist tissue) to the market. These products are used by practitioners of traditional photogravure etching and by commercial printers.

Digital direct-to-plate photogravure

Donald Farnsworth at the art workshop Magnolia Editions
Magnolia Editions
Magnolia Editions is a fine art studio in Oakland, California. Founded in 1981, Magnolia Editions publishes fine art projects, including unique and editioned works on paper, artist books, and public art...

 developed a digital direct-to-plate photogravure process that does not use gelatin. Instead, a series of 'masks' (layers of resist) are printed onto a copper plate using a flatbed UV cured acrylic printer: “The flatbed printer allows us to etch a stochastic [random] dot pattern into the plate in a completely controlled, precise way... This process is an inversion of the traditional photogravure method, where you’re etching through a sheet of gelatin, and gradually the gelatin is getting thinner and more acid reaches the plate, so the last thing that’s etched are the light tones.”"Direct to Plate Photogravure: Catching Up With the Past." Stone, Nick. Retrieved 2009-04-13. Instead, the digital direct-to-plate method requires that the light values be etched first; then the printer is used to lay down a new layer of ink onto the plate between acid baths, masking out the lighter values to protect them from subsequent etches. The initial mask looks like it has barely been printed; the masks grow in density until the plate eventually appears almost completely black.

In another variation of the traditional process, where the acid baths are increasingly watered down as the process unfolds, the direct-to-plate process begins with a weak bath and is gradually etched in baths which are increasingly acidic.

Photo-polymergravure / Polymer Photogravure

Photopolymer plates, usually used for relief and letterpress printing, can be used to make photogravure plates. These polymer
Polymer
A polymer is a large molecule composed of repeating structural units. These subunits are typically connected by covalent chemical bonds...

 plates, when developed, are like a hard plastic, which allows for fewer impressions to be made. Some feel that they rival the quality of traditional copper plate photogravure, while others find that the lack of differential depth in the polymer coating compromises quality.

The process involves a series of exposures of the polymer plate. First, it is exposed under strong light with a random dot screen placed above it (called an aquatint screen in fine art printing and a stochastic screen in commercial printing). Next, the plate is exposed with a positive transparency of an image. This transparency can be a continuous tone positive on film, but is most often made as a digital 'positive' (made in the same way as a digital negative
Digital negative (transparency)
The digital negative is a new technology which allows photographers to use digital files to create negatives on transparency film. These negatives can be used to contact print, or in some cases if the negative is made large enough they can be enlarged...

]) printed with an inkjet printer. The plate is then developed; for many types and brands of plates, this is done in water.

After proper drying and curing, the plate can be inked and printed. The dual exposures produce an "etched" polymer plate with many thousands of indentations of varying depth which hold ink, which in turn are transferred as a continuous tone image to a sheet of paper. Depending on the quality, the resulting image may look similar to or the same as those produced with the traditional photogravure process, though without their three-dimensional depth.

Two polymer plates commonly in use are Printight plates made by the Toyobo
Toyobo
is one of Japan's top makers of fibers and textiles, including synthetic fibers and natural fibers, such as cotton and wool. The company's textiles are designed for clothing, home furnishings, and for industrial uses. Its textiles include spandex yarn for apparel, polyurethane fiber for pantyhose,...

Corporation and Solarplates.

External links

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