The benefit to such time intensive techniques is the ability to then make multiple prints with negligible variation, at full production speed.Ĭontact printing was also once used in photolithography, and in printed circuit manufacturing. Dodging can be accomplished by placing fine tissue paper on the intermediate glass stages between the light source and the negative/paper sandwich to modify the exposure locally.
They typically combine in a box the light source, intermediate glass stages, and a final glass stage for the negative and paper to be placed upon, as well as an elastic pressure plate to keep the negative and the paper in tight contact. Images from smaller formats may be transferred to a larger format negative for this purpose.Ĭontact printing machines are more elaborate devices than the more familiar and widely available contact printing frames. Medium or large format negatives are almost always used for these types of printing. Some alternative processes or non-silver processes, such as van Dyke and cyanotype printing, must be contact printed. "Burning" and "dodging" (either increasing the amount of light that one area of the print receives, or decreasing the amount of light in order to achieve the ideal tonal range in a particular area) require painstaking work with photographic masks, or the use of a production contact printing machine (Arkay, Morse, Burke and James are manufacturers who make contact printing machines). When large format film is contact printed to create finished work, it is possible, but not easy, to use local controls to interpret the image on the negative. However, the exposure value (EV) range, the variation from darkest to lightest regions, is inherently greater in negatives than in prints. A disadvantage to using contact prints in the fine-arts is the laboriousness of modifying exposure selectively, when the use of an enlarger can achieve the same purpose.īecause light does not pass any significant distance through the air or through lenses in going from the negative to the print, the contact process ideally preserves all the detail that is present in the negative. In medium and large format photography, contact prints are prized for their extreme fidelity to the negative, with exquisite detail that can be seen with the use of a magnifying glass. For 120 roll film (once a common negative size for popular cameras) and larger film, contact prints are often used to determine the final print size. Contact prints are used to produce proof sheets from entire rolls of 35 mm negative (from 135 film cassettes) and 120 (2 1⁄ 4 film rolls) in order to aid in the selection of images for further enlargement, and for cataloging and identification purposes. Since this process produces neither enlargements nor reductions, the image on the print is exactly the same size as the image on the negative. Īnsel Adams describes procedures for making contact prints using ordinary lighting in his book, The Print. Failure to adhere precisely to this process will result in a poor-quality final image with a variety of issues. The paper must be placed in a film developer bath, a stop bath, fixer, and finally the hypo-eliminator bath, in that order. The paper is then developed and the result is called a contact print.Īfter exposure, the paper is processed using chemicals in the darkroom to produce the final print. A hinged top-cover presses the negatives in close contact with the paper and keeps them in place.
The negative and the photographic paper are placed on the glass plate of the exposure box. Accurate timing of the light comes with experience, but only a little experimenting leads to positive results. The light may come from a low wattage frosted bulb hanging above an easel which holds them together, or contained in an exposure box with a plate of frosted glass on top. One or more negatives are placed on a sheet of photographic paper which is briefly exposed to a light source. Its simplicity avails itself to those who may want to try darkroom processing without buying an enlarger. Photo by Paolo Monti, 1975.Ĭontact printing is a simple and inexpensive process. Contact print of a photo film cut in pieces, used for reviewing and selecting images for the final print.
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