This varies with application. For a stationary camera setup, the Core, Bridge and motor(s) are placed on the camera. In a moving camera setup, you’ll also need to mount a Pack and Sensor to the camera UNLESS an Ambit is mounted on the camera. The Core and Bridge could also be placed in a pouch on the camera op when doing a mobile shoot, to eliminate weight from the camera, so long as the motor cable can reach the motor.