The meter and focus function of the camera can be held in position continuously with the Quantum 2-Step Motor Drive Cord.With this Quantum FW-41 Motor Drive Cord, you can keep the camera in the instant shutter release positionThe Quantum Freewire allows you to instruct your camera to “wake up”, focus, and meter by selecting the motor drive “delay”The shutter of the camera can be released after commanding the cameraThe Quantum 2-Step Motor Drive Cord is compatible with the Contax 645 camera