Collotype — Process

Collotype came into existence sixteen years after photography was invented in 1839. Early on, it served as a photographic medium as well as a print medium, due to the fact that the carbon ink it used, unlike silver printing at the time, resisted fading. Since that time, collotype printing has evolved in such a way that it can open up to photographers new avenues of creative exploration. The color collotype introduces new tonal subtlety and variety. Its ability to print on handmade paper and silk extends the creative potential of photographic images beyond the limits of conventional photographic paper. Most important, perhaps, exposed film can be used directly for plate making, bringing the collotype image a step closer to the artist's original vision. Digital technology is incorporated into the collotype process, the studio's elite printers are taking advantage of the new choices it opens up to develop new techniques and push the limits of creative expression even further.

Throughout the history of photography, creating images has meant making choices: black and white film or color, gelatin silver print or alternative photo processing. Now, artists are experiencing a new level of freedom as they weigh the possibilities of digital technology against those of traditional film and chemical processes.

As artistic vehicles, technology and tradition are by no means mutually exclusive, nor are they constrained to conform to any set value hierarchy. On the most fundamental level, the technological and the traditional serve to dimensionalize each other. The speed and precision of digital techniques exist not only as values in themselves and as avenues of exploration, but as a backdrop against which we can appreciate all the more the warmth and ineffable uniqueness of handmade prints.

Photographing

• A large format camera is utilized to produce negatives that most faithfully regenerate the original in full scale. The maximum size allowance for the original is 50.8cm x 61.0cm (20"x24"). All black and white films are specially ordered.
• The original colors are decomposed to make single color negatives using one of the 4 filters (purple, green, red, yellow) from the 3 primary colors,
• Plate making technicians check color decompositions against a color compostite swatch book.

Negative Adjustment

• The single color negatives go through a retouching process. The technicians adjust each negative according to the original masking, coating, pressing, ect. Upon completion, the negatives are ready to be made into individual color plates. This hand made process requires exceptional workmanship.
• In extremely complex color situations, over 10 negatives are produced for printing.

Plate Making

• After coating a sheet of 10mm round glass with a solution of dichromated gelatin, the negative is sealed on top of it for exposure. During which the dichromated gelatin reacts to the amount of UV light passing through the negative, causing it to harden in proportion to the tones of the image. The hardening reaction makes the gelatin the least absorbent in the tones receiving the most light, and the most absorbent in those receiving little or no light.
• The most valuable strenght of color collotype printing is its ability to produce admirable color images without the use of screens - in continuous tones. Depending on the exposing circumstances, the tone of the negative will reflect accordingly on the hardening gelatin. Thus, giving it a sculpted like uneven surface that is responsible for the registration of continuous tone.

Color Correction

• Prior to actual printing, tests are printed with respect to the original image. Where color strenght, tone and ambience are all carefully checked and amended. Based on the test results, it sometimes goes back to the plate making process for additional touch ups.

Printing

• To make prints, the plate is dampened with a solution of glycerin and water.
• This solution is absorbed by the gelatin in proportion to the tones in the image. The darkest tones absorb little or no moisture while the lighter tones and non-image areas absorb the most.
• When greasy collotype ink is rolled over a fully dampened plate the non-image areas holding the most moisture repel the ink, while the hardened image areas attract the ink. Subtle highlights holding the most moisture attract the least ink while the deep shadows holding the least moisture attract the most ink. Consequently, a full continuous tone image is formed.
• During printing, paper is hand fed into the printer one sheet at a time.
• Hand printing is done while monitoring the color printing process. When one is done the next color plate gets exchanged for printing.

Color Layering

• The separated colors are printed back together in layers one after another. To avoid contortion, printing papers are left hanging at room temperature for over a month for acclimation. Since all ink colors are results of specific mixtures of various pigments, the relative color combination and proportion of the anticipated composition under go careful analysis for layer printing. It is a meticulous process that demands perception and experience. The plate makers judge and predict on every color print at every stage and adjust for the subtleties accordingly. Upon which necessary additional colorings are sometimes performed prior to completion.