From Digital to Cyanotype

Alternative processes for photography are most often UV light sensitive only. Because UV enlargers do not exist, you need a negative the same size as the final print for contact printing. In the past this has mostly been done with either in camera original negatives (using large format view cameras to produce the negative) or enlarged negatives using copy film. Tillman Crane, an accomplished photographer and platinum printer, has an extensive description on how to produce an enlarged negative in a traditional darkroom.

The resurgence of interest in alternative photographic printing in relative terms just preceded the emergence of widespread digital photography. William Crawford's The Keepers of Light published in 1980 was a guidepost for many early re-practitioners of  these processes.

Photography exists primarily for the masses and for commercial use to communicate, influence and store memories. Insofar as widespread commercial use overlaps the needs of the artist, materials are available for the artist's use. As digital photography began replacing traditional photography across a broad spectrum of the photographic business (event and sport photography, photojournalism, consumer) sources of materials for traditional film-based photography - including material for making enlarged negatives for contact printing - began disappearing.

I think it is this ability to blend the old alternative processes with new digital methods for making negatives that will rapidly emerge as the standard approach to making traditional photographic prints. 

At the top of this article is a (transmission) scan of the digital negative I created to produce the cyanotype print below. Using Mark Nelson's Precision Digital Negative system. I calibrated the traditional cyanotype process using step tablets to determine an ink combination to produce a negative on Mitsubishi Ultra Premium Pictorico film on an Epson 3800 with full tonal range and densities calibrated to the process, chemistry, paper and light source. Digital negatives are created on transparent film using dye or pigment based inks. It is obvious that the negative is not black and white as is a silver negative. Exploiting the different UV blocking capabilities of the different colors of ink in a printer is key to producing high quality digital negatives.

The second image above shows the coated sheet of Arches Platine paper with the cyanotype emulsion before exposure. The digital negative is sandwiched ("emulsion" to emulsion) and placed in my built-in vacuum frame in my custom UV exposure unit from Edwards Engineered Products.

My exposure time is 3 minutes and 32 seconds, which is quite a short exposure for cyanotypes. As the image just above shows, cyanotype is a printing out process, which means the image is fully created during exposure. Traditional silver gelatin printing is a developing out process which shows no image whatsoever until the exposed print is subjected to chemical action by the developer. Some processes like palladium printing are partial printing out process where the developer completes the visible changes started during exposure. For the exposed cyanotype, the paper is cleared of unexposed emulsion by placing it inverted in a tray of water, ensuring there are no trapped air bubbles under the paper, and letting it stand for 8 - 10 minutes. The goal is to remove all of the yellow emulsion stain from the image. Depending on your paper, your wash time may be longer. Following clearing, a 30 second dip in a tray of water to which a splash of hydrogen peroxide solution has been added will bring the image to full intensity immediately. The step is unnecessary if one has patience as the image color will strengthen to the same end result in 24 hours or more. I let the print drip free holding it by a corner, and then lay it flat on a paper towel. I take a roll of blue shop paper towels and roll it over the print to remove any surface water remaining and then allow the print to dry. Alternately you can simply hang dry the print. The print may be flattened in a press for final mounting and presentation.

I have a lot more to cover about digital negatives and alternative processes!