Spot or area in the frame marking the position where the autofocusAutofocus (AF) is an optical system that uses a sensor, a control system and a motor to focus on an automatically or manually selected point or area. The process of autofocusing generally works as follows: • An autofocus processor (AFP) makes a small change in the focusing distance.
• AFP reads the AF sensor to assess whether and by how much focus has improved.
• Using the information from (2), the AFP sets the lens to a new focusing distance.
Autofocus systems can be found on film and digital cameras. system takes readings to set the focus.