All images on the website are handmade monoprints either by contact printing processes (gum, cyanotype, platinum/palladium, and combinations thereof) or by wet darkroom processes (hand colored gelatin silver, gelatin silver mordançage, chromoskedasic sabattier, etc.). Instructions on how to do the processes are in the books for purchase on the Books page. Below is a description of several of the processes used.
Gum prints are essentially photographically controlled watercolors. The prints are made in a 19th Century process called gum bichromate or dichromate, or gum printing for simplification. Even though the image resembles a color photograph, it is only a fabrication of pigment and hardened gum arabic. Gum arabic is mixed with watercolor paint and a photosensitive substance called ammonium dichromate, and painted onto watercolor paper. When exposed to sunlight in contact with an enlarged negative, the gum hardens into an image that is “developed” in plain water. Where the light hits the most, the gum hardens the most and creates the shadow areas of the image. Where the light hits the least, the gum and pigment wash away proportionately, leaving the highlights of the image. For each print, this exposing and development process is done three or more times, layer upon layer—first blue, then yellow, and finally magenta for tricolor gum. Each print takes several days to complete. The prints, when finished, are completely archival.
Casein prints are the same as gum prints except the colloid used is casein or milk protein. The casein is precipitated from cottage cheese or milk by using an acid, and then mixed with ammonia to liquify it. At time of use this is mixed with watercolor pigment and dichromate, brushed onto watercolor paper, exposed under UVBL light and processed in hot water until an image surfaces. This, then, is done 4-6 times per print over a period of days to achieve a colored image.
The mordançage process was originally called the "bleach-etch" process until Jean Pierre Sudre coined the term "mordançage" (pronounced more-dan-sahhhj). Since my work usually centers on social deconstruction, it is fitting that I use a photographic process to physically deconstruct the photograph itself and, along with it, the sanctity of the pristine black and white print. In the mordançage process, a caustic, acidified copper bleaching solution is used to bleach and dissolve away the silver image. It leaves the print in a reverse relief—in other words, the dissolution occurs proportionately to the darks. With a little rubbing, the solubilized silver gelatin layer lifts off of the print and leaves behind whites in reverse relief where the darks once were. Complete rubbing produces a reversed or more negative image, but more often than not, some positive remains because the original highlights and midtones in the print are not as affected. If there are large areas of darks in the print, these areas can be left attached as veils. The print can be redeveloped, toned, or dyed after the bleaching and rubbing to produce colorful and uniquely altered prints.
In chromoskedasic sabattier, which is actually a photo+chemigram, a freshly developed but not yet fixed black and white print is subjected to two mild photographic solutions, an activator and a stabilizer, in the darkroom and out under room light. The activator is a dilute potassium hydroxide; the stabilizer is an acetate buffered thiocyanate. Colors appear where there is white in the print: orange, brown, yellow, pink, purple, green, and blue, as well as silver on normally monochrome black and white paper. All of these colors are the result of the “Mie” effect. To explain the Mie effect, a black and white print is normally monochromatic because the silver particles that remain in the print after fixing absorb all color and reflect black. In chromoskedasic printing, the silver particles are carefully managed with different chemicals with or without exposure to light, to become different sizes. These different sized silver particles scatter light in different ways to produce the different colors. Smaller particles will look yellow; larger particles will look red.
Salted paper is as old as the invention of photography, which by art history standards is a comparatively young art of a mere 180 years. It was the first photography-on-paper process invented and it became the basis of black & white photography as we know it today. A piece of paper is soaked in salted water, dried, and then coated with silver nitrate, exposed in the sun, toned with gold and other precious metals, and what results is a monochrome print of various colors: yellow-browns, peachy-browns, red-browns, lavender-taupes, purple-reds, dramatic aubergines to neutral dusky blue-blacks. The process can be printed on any kind of paper, not to mention fabric, leather, wood, glass, and ivory. Salt has the longest exposure scale of any photographic process. From highest delicate highlights to deepest shadows, all detail is preserved. It is the process to use when wanting to connect to photography’s historical roots.
|© 2018 Christina Z. Anderson. All Rights Reserved.
Powered by VisualServer™|