Academic journal article Transactions of the American Philosophical Society

The Collodion Gallery

Academic journal article Transactions of the American Philosophical Society

The Collodion Gallery

Article excerpt

The simplicity of the collodion process made it easy to become a ferrotype operator, but innovation and the ability to adjust to the demands of a costconscious public kept the operator in business. It was simple and, compared to earlier processes, inexpensive. Little additional assistance was needed to prepare, expose, or develop a plate, and photographic stock houses provided all the necessary supplies: camera boxes and lenses, trays and pans, posing chairs and headrests, iron plates in various sizes, chemicals, colors, varnishes, frames, cases, albums, card mounts, and envelopes. Although a few ferrotype operators experimented with alternative black surfaces, most did not.

In 1860 Simon Wing's multiplying camera gave operators the tool by which they could make many images on a single prepared plate. This innovation meant more ferrotypes could be made faster and cheaper. In addition, new plate manufacturers vied for their share of the photographic market, which made japanned plates cheaper and the ferrotype portraits made on them correspondingly less expensive.

Except in big cities, the large, elegant photographic establishment gave way to the much less resplendent skylight gallery, the traveling car, and the portable house and tent. Even with such creative responses to the market, making ends meet was not always easy. Competition was fierce and profit margins were thin.


Although chemical formulas for making collodion positives on japanned iron plates varied during the nineteenth century, the process itself was quite simple.1 The iron plate was coated with collodion containing iodide and bromide, which was then allowed to congeal. First collodion was poured onto the surface of the plate, which was tilted until it was covered, then the excess was allowed to drain from one corner back into the bottle. Sometimes the collodion on that corner was pinched off by the operator, leaving a fingerprint behind. Since this part of the process had to be done quickly and the operator knew that all corners would be hidden under a brass mat, the remaining three corners of a standard-size plate were often deliberately missed. Less time was thus spent in preparing the plate, and less collodion was used (fig. 35). In the dark closet, the plate was then sensitized in a bath of silver nitrate solution for one to two minutes, removed, drained, and placed in a plate holder while still wet. The surface at this point had a creamy, opaque appearance. The plate was then slipped into the camera, ready for exposure.

Length of exposure time could vary, depending upon the formula and age of the collodion, the strength and color of the light, the focal length of the lens, and the color of the subject's clothing.2 According to Albion K. P. Trask in 1872, a ferrotype required twice as much light as a collodion negative. Exposure time was eight seconds when the light was sufficient. More time was required on a cloudy day.3 After the plate was exposed, it was removed from the holder in the dark closet and then developed by pouring a solution of sulfate of iron over the plate until it covered the surface. The plate was then gently rocked in the operator's hand until the development was completed, washed in water, and then immersed in a solution of cyanide of potassium for three to five seconds to fix it. After a second washing, the plate was taken to the drying stove or spirit lamp. Caution was necessary when drying the plate, as extreme heat could cause the japanned surface to blister.

Tinting, if desired, was added next. Dry colors were applied with a soft camel hair pencil brush. Surplus color was brushed off with a wide brush, also called a blender. Too much color could also be removed by using a brush that had first touched the skin; moisture from the skin would cause the pigment to adhere to the brush. Although James Newman, a London manufacturer, offered sets of thirty-six dry colors in glass tubes, most American photographers were satisfied with a more limited palette. …

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