Nikon D200 D200 User's Manual - Page 80

Reference-Exposure Autoexposure Lock When center-weighted metering is used, an area in the center of the frame is assigned the greatest weight when determining exposure. Similarly, when spot metering is used, exposure is based upon lighting conditions in the selected focus area. If the subject is not in the metered area when the picture is taken, exposure will be based on lighting conditions in the background, and the main subject may be under- or over-exposed. To prevent this, use autoexposure lock: 1 Select exposure mode P, S, or A and choose center-weighted or spot metering (exposure lock has no effect in exposure mode M). If using center-weighted metering, select the center focus area with the multi selector ( 53). 2 Position the subject in the selected focus area and press the shutter-release button halfway. With the shutter-release button pressed halfway and the subject positioned in the focus area, press the AE-L/AF-L button to lock exposure (and focus, except in manual focus mode). Confirm that the infocus indicator (●) appears in the viewfinder. While exposure lock is in effect, an AE-L indicator will appear in the viewfinder. 3 Keeping the AE-L/AF-L button pressed, recompose the photograph and shoot. 70