B4: Center-Weighted Area; B5: Fine-Tune Optimal Exposure; C: Timers/Ae Lock; C1: Shutter-Release Button Ae-L - Nikon D7100 User Manual

b4: Center-Weighted Area

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 6, 8, 10, or 13 mm or to
the average of the entire frame.
Note that the diameter is fixed at 8 mm when a non-CPU lens is used, regardless of
the setting selected for Non-CPU lens data in the setup menu (
Average is selected, the average of the entire frame will be used for CPU lenses.

b5: Fine-tune Optimal Exposure

Use this option to fine-tune the exposure value selected by the
camera. Exposure can be fine-tuned separately for each
metering method by from +1 to –1 EV in steps of
D
Fine-Tuning Exposure
Exposure fine-tuning is not affected by two-button resets. Note that as the exposure
compensation (E) icon is not displayed, the only way to determine how much exposure has
been altered is to view the amount in the fine-tuning menu. Exposure compensation (0 86)
is preferred in most situations.

c: Timers/AE Lock

c1: Shutter-Release Button AE-L

If On is selected, exposure will lock when the shutter-release
button is pressed halfway.
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236
G button A Custom Settings menu
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G button A Custom Settings menu
1
/ EV.
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G button A Custom Settings menu
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