Nikon D6 Reference Manual page 890

e2: Flash Shutter Speed
Choose the slowest shutter speed available with a flash in
modes P and A.
Regardless of the setting chosen for 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
[Entire
Y E
frame]
[Background
E
only]
838 A Custom Settings: Fine-Tuning Camera Settings
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.
Description