Monsieur Merlen, 1861. A small photograph mounted on card stock, called a carte-de-visite, was patented by Disd?ri in 1854. Used for images of both ordinary and famous people, it gave birth to the craze of collecting celebrity portraits. By 1862 Disd?ri had 90 employees producing over 2,000 prints a day, making him reputedly the world?s richest photographer. In contrast with the daguerreotype medallion portrait, carte-de-visite prints were economical and inexpensive. A camera with four lenses and a sliding plate holder produced eight sequential exposures on a single glass negative. The resulting paper print was cut up and the individual images were mounted. This uncut sheet was probably a proof produced for the sitter?s approval.