ABSTRACT
Most cameras have an autofocus setting, which may be easily relied upon for most everything that the average user needs. Most smart-phone cameras or point & shoot cameras are used for taking pictures of friends and family, selfies, or travel destinations. Despite the various challenges, though, the autofocus function has effectively done its job. Autofocus is further divided into active and passive systems, each of which has some limitations in the theatre. When using the active autofocus system in photographer’s camera, there is a special light separate from the flash unit, often found on the right side of the camera near the base of the lens and the viewfinder. The concept is that photographer’s camera sends out a beam of light, and measures that beam upon its return to camera, enabling the camera to derive the distance to the subject.
