Nikon D800 - Manual (Page 313)

En_03
289
U
When calculating exposure, center-weighted
metering assigns the greatest weight to a
circle in the center of the frame. The
diameter (
φ) of this circle can be set to 8, 12,
15, or 20 mm or to the average of the entire
frame.
Note that unless Average is selected, the diameter is fixed at
12 mm when a non-CPU lens is used, regardless of the setting
selected for Non-CPU lens data in the setup menu (
0 212). When
Average is selected, the average of the entire frame will be used for
both CPU and non-CPU lenses.
A
Show ISO/Easy ISO
Custom Setting b4 (Easy exposure compensation) can not be used
with Custom Setting d7 (ISO display and adjustment) > Show ISO/
Easy ISO (
0 295). Adjustments to either of these items reset the
remaining item; a message is displayed when the item is reset.
b5: Center-Weighted Area
G button ➜ A Custom Settings menu