Platinum printmaking was first devised in the 1870’s and quickly became the premier photographic printing process. It offered very fine detail reproduction; a long, smooth tonal range; and archival permanence. In addition, images rendered in platinum have an almost three-dimensional quality and a delicate luminosity that cannot be matched by other printing methods. Unfortunately, rapidly rising platinum prices during and after World War I and the advent of handheld cameras and photographic enlargement of small negatives were virtual death knells for platinum printing. However, the process has been resurrected over the last 30 years and regained its place in the repertoire of modern artisans.
Making a platinum print requires a large photographic negative. That’s because platinum printing is a contact printing process. To make a platinum print, the sensitized printing paper is placed in contact with the negative and exposed, so the printed image is the same size as the negative image. Platinum prints can’t be made by enlargement, like “normal” silver prints are. To make that large negative, I use a wood and brass field camera of the type that has been around for more than a century. It takes sheets of film roughly eight inches by ten inches that are loaded into the camera with (appropriately enough) sheet film holders.
The large format camera is much more complicated than it might at first appear. On it’s front standard is mounted a lens, aperture, and shutter assembly, which may be turned left and right (swing movement); moved straight up, down, left, and right (rise, fall, and shift); and tilted up and down (tilt). On the rear standard is mounted a translucent sheet of glass (the ground glass, which is approximately the same size as the film being used) onto which light from the lens is focused. Between the two standards is a bellows, which allows the front and rear standards to be moved closer together or farther apart when focusing the image. To further complicate things, all these parts fold neatly into the rear standard for transport and storage. The camera’s movements are used to compose the image and selectively focus on the subject being photographed.
Operating a large format camera begins with mounting it on a tripod to support its substantial weight (mine more than 20 pounds with a lens and film holder installed). Then, the camera is unfolded, the lens is mounted, and the camera’s movements are adjusted to compose and focus the subject’s image on the ground glass. While adjusting the camera, the photographer hides away under a darkcloth to shield the ground glass from ambient light, making it easier to see the image.
Once all the controls are set and locked, a film holder is inserted into the camera between the ground glass frame and the camers’s back. The darkslide is then removed from the film holder to uncover the film, the aperture and shutter speed are set, and the shutter is cocked. After the shutter has been released, the darkslide is reinserted into the film holder, and the film holder is removed from the camera. To say the least, this isn’t exactly a “point-and-shoot” operation.
When we arrive back at our studio, the exposed film is removed from the film holders and processed. Because each sheet if film only has one image captured on it, we can develop each sheet differently to accommodate for each image’s particular needs. Roll film (like that used in 35mm cameras), on the other hand, is usually developed as a multi-image strip, which doesn't allow the development flexibility we have with sheet film. Specific development allows us to control the film’s apparent sensitivity to light, graininess, contrast, and tonal gradation.
Now that we have a large negative, we can begin making a platinum print. As a base for the print, we use very high quality, heavyweight artist's paper specifically designed for platinum printing. This paper has a relatively smooth finish, which makes coating easier and ensures the image’s fine details will be reproduced. The light sensitive coating, a liquid compound of platinum salts and other chemicals, is applied with a brush or glass rod on one side of the paper and allowed to dry. By modifying the coating chemistry, we can control the tone of the printed image from warm, red/brown-blacks to cool blue-blacks, as well as set the image’s contrast range.
To expose the print, the negative is pressed against the coated side of the paper, and high-intensity UV light is shone through the negative. Exposure usually takes from four to eight minutes, compared to less than one minute for modern silver enlarging paper. After exposure, the image is developed in an acidic bath, which causes metallic platinum to deposit in and on the paper where the coating was exposed to UV light. (Different developing agents and different development temperatures can also be used to change the print’s appearance in much the same way as altering the coating chemistry.) The print is then run through a series of chemical baths to remove any unexposed coating and washed to remove any traces of development and clearing chemistries.
After drying, the now curled print is cold pressed to flatten it. Some platinum printers coat their finished prints with conservator’s wax to deepen blacks and produce a semi-gloss sheen, and others hand color or use other printing processes on top of the platinum image to further “enhance” their prints. Currently, I do neither, but I am always experimenting to find new ways of expressing myself.
Making a single platinum print can easily require several hours of work, between loading, shooting, and processing the film and coating, exposing, processing, and finishing the print. Compare that with the digital photographer’s almost instant gratification or the modern film photographer’s less than an hour to go from loading film in the camera to an enlarged print. But a finished platinum print is worth the extra effort. It has a unique, almost glowing appearance, captures even the most delicate details of the subject, and withstands the ravages of time, a combination not found in any other photographic printing method.