The following is an introduction to the process of photogravure, written by this month’s solo artist, Jenny Freestone. Several examples of her photogravures are here, and there are more in the current show. Also read Jenny’s introduction to Lithography, another technique represented in her solo show.
The Photogravure print contains the detailed tonalities of a photograph combined with the surface texture of an etching and the rich depths of an aquatint, giving the best traits of both intaglio and photography on one archival support. The potential for use of different papers and inks adds endless opportunities for experimentation. The copper plate itself can be reworked, added to or altered after the photogravure process has taken place. The plate will print a large edition.
The image to be used for the process can be a photographic positive or slide (re-sized in the darkroom), a digital photograph or digitally made image printed onto transparent film, or an image drawn/made on a translucent surface such as mylar.
The image is transferred to the copper plate as follows. The image is exposed via UV light source to photosensitized gelatin tissue. The gelatin tissue holding the image is adhered to a copper plate and developed. The plate is then ready for etching. At this point the image is held in a layer of gelatin on the surface of the copper plate. The dark areas of the image hold a very thin coating of gelatin, and highlight areas a thick coating – with a wide tonal gradation in between. During the etching process, the water content of the acid will dissolve the gelatin and allow the acid to start biting the metal underneath. The action of the etch will begin in areas with a thin coating of gelatin (black areas), and proceed through baths of acid with higher water content, etching through the mid tones and ultimately the highlight areas of the image. The plate is then ready for proofing. After proofing, the plate has to be cut to the image size, as safe areas have been kept around the image throughout the process. The plate is then ready for printing and editioning.