21 METERING SENSITIVITY AREAS21 Metering Sensitivity AreasWith the New Canon F-1, a special optical element in each focusing screen de-termines the metering sensitivity area. Thus the metering area can be changed,according to the sub ect you are shooting and the lens in use, simply by replacingthe focusing screen.There are three different light measuring areau available, each designed to suit par-ticular metering requirements.1. Center-weighted Average MeteringWith this system, the meter reads the entire viewing area with special emphasis onthe central portion where the subject is most likely to be. It can be used for generalphotography, and is recommended especially for AE photography.2. Selective-area MeteringThe selective-area system, with its 12% coverage, allows you to meter a certainportion of a scene. It, too, is suited for all-around use, and is particularly effectivefor metering highcontrast scenes, such as landscapes with a bright sky and backlitsubjects. Manual exposure is recommended for optimum results. This system canbe used for AE photography, but special attention must be paid to ensure that thesubject is within the 12% metering area.42