Photogravure
Photogravure is as old as photography itself. Two of the key innovators of photography - Nicéphore Niépce in France and Henry Fox Talbot in England - were experimenting with photomechanical platemaking even around the time of the first fixed photograph in 1839.
Fixing silver halides on paper was one thing, but being able to rapidly reproduce the image durably and inexpensively for potential worldwide circulation was considered equally important from the start. Accordingly, the 19th Century reached back to the 15th-Century to borrow its old etching press, creating a new way to rapid-copy photographic impressions in ink.
(Daniel Hopfer’s and Albrecht Dürer’s copper etchings from the late 1400s are the best examples of early intaglio HAND-artistry that would have recommended intaglio printing to the thoughts of the 19th-Century photo-innovators.)
Fox Talbot’s method of producing intaglio plates by etching through a bichromated gelatin film and Niépce’s wax paper “transparency” technique registered the initial possibilities. But then, by the 1840s and 1850s, Daguerreotype and wet plate collodion had ascended as the de facto photographic standards.
Only in 1879, did Karl Klič in Czechoslovakia introduce cylindrical plates the first efficient and reliable method of producing photogravures which ushered in their wider popularity.
(Artists working in photogravure in the late-19th and early-20th Century include: Peter Henry Emerson, Alfred Stieglitz, Alvin Langdon Coburn, Edward Curtis, Paul Strand and of course many others.)
Klič’s influence is palpable today in the Rotogravure systems that newspapers and duo- and tri-tone offset printers used until quite recently to reproduce images in mass quantities, for example for book publication. These rotogravure rigs have largely been replaced now by digital systems in the offset printing house and by inkjet printers on the computer desktop.
So it goes.
The irony of Photogravure’s art-studio revival today is striking: mastery of the digital inkjet printer supplies the post post-modern gravurist with a tone scale more sublime than ever in history.
“Of all photoengraving methods there is none which produces such rich and satisfying results as photogravure. The reason for this is to be found in the method of printing. It is an intaglio process and, therefore, the quantity of ink which is transferred to the paper can be considerable, and it shares with mezzotint among hand engraving processes the resulting richness of tones.”- Captain Herbert Mills Cartwirght, 1930
The Process in Brief
1. A film positive is created from a photographic negative, digital file, or artist’s marks on transparent material.
2. A sheet of gelatin tissue is sensitized in a bath of chilled potassium dichromate. The sensitized gelatin tissue is squeegeed, gelatin side down to a sheet of Plexiglass and allowed to dry.
3. The dried gelatin tissue is exposed to the positive. During exposure the gelatin is hardened in proportion to the amount of light the gelatin receives through the positive. The action of light on the sensitized gelatin renders the more exposed areas of gelatin harder than the less exposed areas.
4. The exposed gelatin tissue is placed in a bath of chilled water or a mix of alcohol and water upon a sheet of mirror-finished copper. The tissue and plate are removed from the water and the tissue is squeegeed firmly on to the copper sheet.
5. The sandwich of exposed gelatin tissue and copper is allowed to dry from 5 to 45 minutes. During the drying period the gelatin contracts, creating a firm bond with the copper.
6. The dried gelatin on copper is submerged in a tray of hot water. The hot water dissolves the lesser-exposed gelatin and the image is revealed in relief in gelatin. Once development is complete the image is clearly visible in densities of gelatin on the plate.
7. The plate with the image in gelatin is dried.
8. A windvane in a large box containing very fine acid resistant particles is revolved creating a cloud of the particles. The plate is placed in the box and the particles settle on the plate. The plate is removed when approximately 50% of the plate is covered. The plate is heated and the particles are fused to the plate.
9. The back of the plate and any other areas of the copper not to be etched are protected with an acid resistant paint.
10. The plate is etched in a series of ferric chloride acid baths. The acid penetrates the gelatin tissue and around the aquatint particles leaving tiny pits in the plate. The darkest areas of the image are the most deeply etched. The highlights receive the least etching.
11. The plate is rolled with etching ink, wiped by hand with a starched cloth and run through an etching press with a sheet of art paper. The ink is transferred from the plate to the paper. Gravures are printed in much the same manner in which Rembrandt’s or Goya’s etchings were printed.