the photographic single-lens reflex camera (slr) was invented in 1861 by thomas sutton, a photography author and camera inventor who ran a photography related company together with louis désiré blanquart-evrard on jersey. only a few of his slr's were made. the first production slr with a brand name was calvin rae smith's monocular duplex (usa, 1884). other early slr cameras were constructed for example by louis van neck (belgium, 1889), thomas rudolphus dallmeyer (england, 1894) and max steckelmann (germany, 1896), and graflex of the united states and konishi in japan produced slr cameras as early as 1898 and 1907 respectively. these first slrs were large format cameras. while slr cameras were not very popular at the time, they proved useful for some work. these cameras were used at waist level; the ground glass screen was viewed directly, using a large hood to keep out extraneous light. in most cases, the mirror had to be raised manually as a separate operation before the shutter could be operated.