Aperture-priority AE with high-precision light metering The camera uses a precision silicon photodiode (SPD) aperture-priority exposure system for highly accurate center-weighted metering. The diagram shows the metering pattern for an 80mm f/4 lens. Changing to a wider-angle lens automatically shifts the system to spot metering, while a telephoto lens initiates an averaging system that also take surrounding light into consideration. In the AE Mode, priority goes to the most accurate exposure for the lens in use. The result is highly accurate AE Mode settings under virtually any type of conditions imaginable, from standard lighting to condition where there is a wide range of illumination. Of course, AE lock is also provided to give the photographer the versatility needed when faced with backlit subjects and other conditions where there is strong contrast between subject and background lighting.