Mammoth camera, a huge camera custom designed by the Chicago photographer and inventor George R. Lawrence in 1900 in order to photograph a complete train owned by the Chicago & Alton Railway. It was 6.1 m (20 ft) long when fully extended and, with its 227 kg (500 lb) plate holder, weighed 633 kg (1, 400 lb). The plate itself measured 2.44 × 1.37 m (8 × 4 1/2 ft). A single, 2 1/2-minute exposure of the train was made, and three contact prints sent to the Exposition Universelle in Paris, where the picture won the ‘Grand Prize of the World for Photographic Excellence’.