Triggering
Remote cameras can be fired via hand triggers, radio transmitters, or the self-timer built into the camera.
For remotes that are in close proximity to the photographer, hand triggers can be used. A hand trigger consists of a button or switch that is connected to the camera via a wire that is set to fire the camera's shutter.
For remotes that are placed away from the photographer, radio triggering systems such as Pocket Wizards or Flash Wizards are used. A radio trigger consists of a button or switch that is connected to a radio triggering transmitter or transceiver which is set to fire a radio triggering receiver or transceiver that is connected to the camera via a wire that is set to fire the camera's shutter.
For rocket launches, including the Space Shuttle, remote cameras are triggered by the sound of the launch.
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