Nikon Z 7 Reference Manual page 309

The following options are available:
Option
t
Power aperture
(open)
q
Power aperture
(close)
i
Exposure
compensation +
h
Exposure
compensation –
b
Framing grid
display
g
Protect
K
Select center
focus point
A
AF-ON
Aperture widens while the control is pressed.
Use in combination with Custom Setting g2
(Custom control assignment) > Fn2 button >
Power aperture (close) for button-controlled
aperture adjustment.
Aperture narrows while the control is pressed.
Use in combination with Custom Setting g2
(Custom control assignment) > Fn1 button >
Power aperture (open) for button-controlled
aperture adjustment.
Exposure compensation increases while the
control is pressed. Use in combination with
Custom Setting g2 (Custom control
assignment) > Fn2 button > Exposure
compensation − for button-controlled
exposure compensation.
Exposure compensation decreases while the
control is pressed. Use in combination with
Custom Setting g2 (Custom control
assignment) > Fn1 button > Exposure
compensation + for button-controlled
exposure compensation.
Press the control to turn the framing grid display
on or off.
Press the control during playback to protect the
current picture.
Pressing the control selects the center focus
point.
Pressing the control initiates autofocus.
Description
Menu Guide > A Custom Settings
285