Nikon D300 - Manual (Page 123)

97
S
A
Auto ISO Sensitivity Control
Noise is more likely at higher sensitivities. Use the [High ISO NR] option in
the shooting menu to reduce noise (see page 263). When a flash is used,
the value selected for [Minimum shutter speed] is ignored in favor of the
option selected for Custom Setting e1 ([Flash sync speed], pg. 288).
Foreground subjects may be underexposed in photos taken with the flash
at slow shutter speeds, in daylight, or against a bright background.
Choose a flash mode other than slow sync or select exposure mode
g or h
and choose a larger aperture.