Silhouettes could be cut from black paper and stuck to a background; painted on the inside of a glass plate or painted on paper or other material such as ivory or plaster. Gold or white details were sometimes added and military personnel were often depicted in coloured uniforms. Subjects were mostly portraits or full-length studies, groups were less common. Some silhouettes were finely executed by skilled artists others quickly produced at fairgrounds and the like. They are precursors to photography in satisfying the desire for cheap portraits, later to be fulfilled by the carte de visite. They also anticipated tintype (and similar) images in being produced at fairgrounds and resorts.

Physionotraces were produced by tracing the contours of the sitter using a pantograph-type of device, the miniature portrait was drawn or engraved on a copper plate.

The process was invented by Gilles-Louis Chrétien in 1784, Bouchardy was his successor. Like the silhouette the Physionotrace can be considered a precursor of the photographic portrait; its semi-mechanical means of production meant that the artist did not have to be highly skilled and the portrait could be produced in a short time at a reasonable cost.