A method for switching focus between objects found simultaneously in an image area from a main camera where the focus of the main camera and a switch between different focus distances is controlled by a remote follow focus unit. A secondary system and a computer system are used to measure the distance to the first and second object simultaneously and continuously. Distance information from the secondary system regarding distance to the first object is used by the follow focus unit as a focus distance to set the focus of the main camera on the first object. Distance information from the secondary system regarding distance to the second object is used by the follow focus unit as a focus distance to switch the focus of the main camera from the first object to the second object. The secondary system and the computer system obtain distance information using a secondary camera system.