The Peter and Paul Fortress
A silhouette (English: /ˌsɪluˈɛt/, French: [silwɛt]) is the image of a person, animal, object or scene represented as a solid shape of a single colour, usually black, with its edges matching the outline of the subject. The interior of a silhouette is featureless, and the silhouette is usually presented on a light background, usually white, or none at all. The silhouette differs from an outline, which depicts the edge of an object in a linear form, while a silhouette appears as a solid shape. Silhouette images may be created in any visual artistic medium, but were first used to describe pieces of cut paper, which were then stuck to a backing in a contrasting colour, and often framed.
Many photographers use the technique of photographing people, objects or landscape elements against the light, to achieve an image in silhouette. The background light might be natural, such as a cloudy or open sky, mist or fog, sunset or an open doorway (a technique known as contre-jour), or it might be contrived in a studio; see low-key lighting. Silhouetting requires that the exposure be adjusted so that there is no detail (underexposure) within the desired silhouette element, and overexposure for the background to render it bright; so, a lighting ratio of 16:1 or greater is the ideal. The Zone System was an aid to film photographers in achieving the required exposure ratios. High contrast film, adjustment of film development, and/or high contrast photographic paper may be used in chemical-based photography to enhance the effect in the darkroom. With digital processing the contrast may be enhanced through the manipulation of the contrast curve for the image.