Making a Carbon Transfer Print
There are 10 main steps in making a carbon transfer print. Here is a quick version of what goes into making a single photograph.
1. Sizing the paper
2. Making the photographic emulsion
3. Making the temporary support
4. Printing the negatives
5. Exposing the negatives
6. Transferring the emulsion to a temporary support
7. Developing the carbon print
8. Transferring the image to a temporary paper support
9. Transferring the image to a final paper support
10. Clearing the carbon print
The Paper: When it takes hours or days to make a single carbon transfer print it’s best to work with the highest quality papers available. Fabriano Artistico, Arches Aquarelle, and Hahnemühle Platinum Rag are all great papers for carbon printing. In order for the image to stick to the paper, it is necessary to size it with gelatin. Gloss of the paper is controlled by applying a thin layer of gelatin to create matte prints or a thick layer to create glossy prints.
The Emulsion: This is a thin layer of gelatin and carbon pigment from which the image will be made. It’s made by mixing water, gelatin, sugar, pigment, and a diazidostilbene sensitizer. This mix is then poured in an even layer over a plastic film and dried in a lightproof room.
The Temporary Support: Single transfer carbon prints are produced by transferring the emulsion directly to the final paper support. This method does not allow for color printing because paper expands and contracts. The solution is to transfer and develop all layers onto a plastic sheet, then transfer the completed image onto paper.
The Negatives: I use between 4-14 imagesetter negatives. This system allows total control over the tonality of the final carbon print, and allows for beautifully smooth tones. Imagesetter negative are much more expensive than inkjet negatives, but the quality in incomparable.
Exposing: The negatives are exposed one by one in contact with their respective emulsions. Light passing through the negative hardens the gelatin, making it insoluble in hot water.
Transferring: The emulsion is soaked in water and sandwiched with a plastic temporary support.
Developing: The sandwich is submerged in hot water and the emulsion is peeled off leaving the image stuck to the temporary support. Now it’s a mess of pigmented gelatin and nothing can be seen, but as the unhardened gelatin washes away the image appears.
The Second Transfer: The plastic sheet is joined with the gelatin sized paper under water and hung to dry. When dry, the plastic sheet is peeled away leaving the image on the paper. Stopping at this step results in a double transfer carbon print.
The Third Transfer: To get a matte print, the image from the second transfer step in sandwiched under water with a final paper support. This sandwiched is then developed just as before. This is called a triple transfer carbon print.
Clearing: There is still a small amount of diazidostilbene sensitizer trapped in the pigmented gelatin. The sensitizer is removed by soaking the print in a bath of potassium permanganate then sodium bisulfite.
Qualities of a Carbon Transfer Print
Collectors and demanding artists prefer handmade prints over machine made prints. Carbon transfer prints have the following characteristics:
Archival Stability: Since the prints are made of pure carbon pigment, they will never fade. The Long Now Foundation chose carbon prints for the gallery that accompanies their 10,000 year clock.
Exclusivity: Even more so than a platinum print, carbon prints are enormously difficult, time consuming and expensive to make.
Paper: Since the photo will never fade, the paper must last as long as possible. I print on the highest quality and heaviest pure cotton watercolor papers available.
Smooth Highlights: A shortfall in most carbon prints. With my method, I can create highlights that transition delicately from paper white without visible grain.
Clarity and Dimension: Tonality in a carbon transfer printing is achieved through thick and thin layers of pigmented gelatin. The dark areas are raised up like relief on a topographical map giving the print an incredible sense of dimension and clarity.
Durability: I have 150 year old carbon prints in the studio that look like they were printed yesterday.
Pigments: Any pigment can be used to create any effect. The possibilities here are endless. For example, look at the print to the right, which was made from natural earth pigments.
Luxurious Texture: The texture of a carbon print is an extraordinary thing. The pigment and gelatin perfectly follow the contour of the fibers of the paper resulting in an image rich in dimension and quality.
One of a Kind: Handmade prints are works of art, not copies of it. Like snowflakes, no two are exactly the same. One can print hundreds of copies of a photo on an inkjet printer, but they are just copies and not original works of art.
