THE TECHNIQUE OF TRADITIONAL HÉLIOGRAVURE
Héliogravure is the oldest procedure for reproducing photographic images. It was first invented in the early 19th century by Joseph Nicéphore Niepce, of France, and later perfected by Talbot, Niepce de Saint-Victor, Baldus and Klic.
The process involves two distinct steps. First, in a complex photochemical procedure that creates the intaglio surface, the photographic image is fixed and etched upon a specially prepared copper plate. The finished plate is then placed on a hand-turned press, and the image is printed onto dampened etching paper using special inks.
This traditional method of héliogravure is variously called héliogravure au grain or héliogravure à plat. Before receiving the photochemical transfer of the image, the flat copper plate is first carefully dusted with rosin powder; it is then heated, so that the microscopic grains of rosin melt into fine droplets and fuse to the metal. It is this that accounts for héliogravure’s exceptional tonal range, for when the plate is subsequently etched, the acid only reaches the copper through the fine interstices existing between these grains. The transitions from light to dark are thus modulated with extreme precision and subtle nuance. Even when examined under a magnifying glass, a héliogravure betrays no screen pattern, unlike images printed using industrial methods such as offset, letterpress or rotogravure.
Héliogravure belongs to the same family of intaglio printing techniques as engraving, etching and aquatint. As such, it requires an especially good quality of thick paper, one that can draw out the ink from the furthest recesses of the etched copper. In like manner, the plate embosses the finished prints, for its form is impressed into the dampened paper as they pass together through the rollers. Printed by hand in limited quantities, each héliogravure is considered an original, and its value is accordingly assured.
HÉLIOGRAVURE TODAY
Héliogravure is praised by specialists the world over, who marvel at its incomparably rich palette of blacks and shades of gray, its breadth of tonal range, its exquisite expressiveness. Yet despite such inimitable qualities, it has all but disappeared in the course of the last fifty years: the costly and time-consuming technique of traditional héliogravure has been abandoned in favor of cheaper, faster modern industrial printing methods, such as offset and rotogravure.
As a result, worldwide there are today perhaps only a dozen individuals — editors, printers and héliographers combined — who specialize in this domain.
In the early part of the 20th century, héliogravure was the method of choice for reproductions appearing in high quality books and for artistic photography. Further renown was secured when American photographer Alfred Stieglitz (1864-1946) employed the technique for reproducing the photographs appearing in his celebrated quarterly Camera Work, which was published from 1903 to 1917. In this golden era, many came to consider héliogravure as an artistic medium in its own right.
[Source: pagesperso-orange.fr]