Olympus IS-1 manual Autofocus AF

Autofocus (AF)

The Autofocus (AF) mechanism automatically

adjusts focus by measuring the distance-to-subject. Focusing is accomplished by a TTL (through-the-

lens) phase-difference detection system. More simply, an AF sensor catches the light reflected

off of the subject, calculates the distance, and activates the lens to focus. The IS-1 AF system is particularly advanced, because it even works in the dark by using an infrared beam of light.

Autofocus is designed to focus on whatever appears in the center of the viewfinder. If you wish to position your subject outside the center of the frame you can use the focus lock (see p. 21). This will also lock the proper exposure (AE lock).

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