Lighting for Photographing Coins and Small Objects

Abstract

Common techniques for direct photography of coins and small objects are surveyed and an alternative method of illumination, called axial is described and illustrated. In the past, direct photographic illustration of ancient coins has often been avoided, particularly in the construction of catalogue plates, because of the unevenness in tone and color from one specimen to the next. Coins eroded by wear are especially difficult to illustrate when the surviving details are obscured by differential toning. For that reason plaster casts, rather than the coins themselves, have often been photographed for illustration. The results make for both a more uniform plate and a clearer reading of many individual pieces. Today the objections to the illustration of a copy rather than an original, the expense of creating numbers of casts, and the more frequent publication of excavation coins have combined to cause a return to direct photography. On site there is seldom the need, or the opportunity, for any but direct photography of the artifact itself; and photography is essential when site materials cannot be removed from the country of origin for study or for comparison with the excavation records. Coins randomly lost (as against hoards) are the most commonly recovered in excavations, and are the most likely to have suffered through wear and corrosion. They present the greatest difficulties for the photographer in reproducing details of type and legend for later study when the coins themselves are no longer available. Since the variable quality of coin surfaces now requires a more careful approach to their reproduction, this article surveys briefly and illustrates common techniques as well as a new method of illuminating the object. The quality of coin reproductions depends on 1) the type of lighting, 2) the orientation of the coin in respect to the light, 3) the film type, and 4) the contrast of the print. Lighting is, of course, the most important factor to be considered in photographing small objects. For a particular coin one type of is usually preferable over another, but it is seldom possible to photograph a series of coins with a single type of lighting. No one type of technique will yield the best result with coins that are bright or dark, well worn or in high relief; and results can vary with the type of metal of the coins. The photographer must consider both the nature of the coin and the purpose of its illustration. The same holds true for other small objects. No one type of is good for all types of objects. The best type of depends on what one wants to show. Basic lighting (pl. 5, figs. 1-2; pl. 6, figs. 6-8) involves a main light, either a flood or a spot, pointing to the object, usually at a 450 angle. A fill light, or killshadow, usually a flood, is placed on the opposite side of the object and at a greater distance from the object than the main light. With worn coins basic usually does not bring out sufficient detail. A better method is called raking light (pl. 5, fig. 3; pl. 6, fig. 9). The source can be a flood, but a baby spot is more efficient. The light is usually no more than 150 above the horizontal. An angle much greater than this would make it basic lighting. Raking light produces intense shadows, which can serve the purpose of bringing out minute details. Usually, however, it is necessary to subdue the shadows a bit. This is easily done by introducing some sort of reflective surface into the light path on the side of the object away from the light source (pl. 5, fig. 4). This surface may be a white cardboard, a silver-painted board, a piece of aluminized Mylar glued on a board, or whatever is at hand. The amount of shadow reduction is easily controlled by varying the angle and/or position of the reflective surface. When using a surface with a fairly high degree of reflection, the photographer can introduce helpful highlights into some of the shadows. My preferred reflector is a small piece of aluminized Mylar glued to a cardboard just large enough to lean on the lens. It gives an ample amount of reflected light, yet it is soft, diffused, and not too harsh. * I wish to thank Theodore V. Buttrey for his valuable advice and assistance. 89 American Journal of Archaeology 90 (1986) This content downloaded from 157.55.39.217 on Mon, 18 Apr 2016 06:46:57 UTC All use subject to http://about.jstor.org/terms 90 FRED ANDEREGG [AJA 90