Nikon Z 8 Reference Manual page 860

D
Metering Areas for FV Lock
The areas metered when FV lock is used with optional flash units are as follows:
Stand-Alone
Flash control mode
i‑TTL
Auto aperture (qA)
Remote
Flash control mode
i-TTL
Auto aperture (qA)
Non-TTL auto (A)
D
Flash Compensation for Optional Flash Units
In i‑TTL and auto aperture (qA) flash control modes, the flash compensation selected with the
optional flash unit or with [Flash control] in the camera photo shooting menu is added to the flash
compensation selected with the [Flash compensation] item in the photo shooting menu.
Metered area
6-mm circle in center of frame
Area metered by flash exposure meter
Metered area
Entire frame
Area metered by flash exposure meter
860
Compatible Flash Units