E2: Flash Shutter Speed; E3: Exposure Comp. For Flash - Nikon Z 9 Reference Manual

e2: Flash Shutter Speed

Choose the slowest shutter speed available with a flash in mode P or A.
Regardless of the setting chosen for Custom Setting e2 [Flash shutter
speed], shutter speeds can be as slow as 30 s in modes S and M or at
flash settings of slow sync, slow rear-curtain sync, or red-eye reduction
with slow sync.

e3: Exposure Comp. for Flash

Choose how the camera adjusts flash level when exposure
compensation is used.
Option
YE [Entire frame]
[Background
E
only]
G button U A Custom Settings menu
G button U A Custom Settings menu
The camera adjusts both the flash level and
exposure. This changes the exposure for the entire
frame.
Exposure compensation is adjusted for the
background only.
A Custom Settings: Fine-Tuning Camera Settings
Description
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