How does the camera assistant decide the zooming ratio of laparoscopic images? Analysis and implementation.

An important factor for defining a good image during laparoscopic surgery is the zooming ratio, which corresponds to the depth of insertion of the laparoscope along its longitudinal axis. However, it is not clear how surgeons (camera assistants) decide the zooming ratio of laparoscopic images during surgery. Conventional automatic camera positioning systems define the zooming ratio "uniformly" based on simple heuristics.