Silhouette

A silhouette is the image of a person, animal, object or scene represented as a solid shape of a single color, usually black, with its edges matching the outline of the subject. The interior of a silhouette is featureless, and the whole is typically 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 media, but were first used to describe pieces of cut paper, which were then stuck to a backing in a contrasting colour, and often framed.

Cutting portraits, generally in profile, from black card became popular in the mid-18th century, though the term silhouette was seldom used until the early decades of the 19th century, and the tradition has continued under this name into the 21st century. They represented a cheap but effective alternative to the portrait miniature, and skilled specialist artists could cut a high-quality bust portrait, by far the most common style, in a matter of minutes, working purely by eye. Other artists, especially from about 1790, drew an outline on paper, then painted it in, which could be equally quick.

From its original graphic meaning, the term silhouette has been extended to describe the sight or representation of a person, object or scene that is backlit, and appears dark against a lighter background. Anything that appears this way, for example, a figure standing backlit in a doorway, may be described as "in silhouette". Because a silhouette emphasises the outline, the word has also been used in the fields of fashion and fitness to describe the shape of a person's body or the shape created by wearing clothing of a particular style or period.

Photography
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.
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