Scientist-Astronaut Edward G. Gibson, Skylab 4 science pilot, turns on a switch on the control box of the S190B camera, one of the components of the Earth Resources Experiments Package (EREP). The single lens Earth Terrain Camera takes five-inch photographs. Behind Gibson is the stowed suits of Astronaut Gerald P. Carr, commander for the third manned mission. The exercise took place in the Orbital Workshop one-G trainer at JSC.
