Deep-sky cameras are designed for long exposures on large deep-sky objects such as star clusters, nebulas or galaxies.
Typical deep-sky cameras have larger sensors to handle the wide fields of view required. They may also have larger pixel sizes for additional sensitivity as well as allowing for a greater field of view.
Because they are intended for long exposures, deep sky cameras have cooling systems incorporated in them. This decreases the amount of noise resulting from the electronic circuitry inside the camera.