Nikon Z fc N2016 Reference Manual page 134

Shutter speed extension
A
If Custom Setting d5 [Extended shutter speeds (M)] is set to [On], you can
select a shutter speed of up to 900 s (15 min) in mode M when the shutter-
speed dial is set to [1/3STEP].
･ If you extend the shutter speed, the exposure indicator will not be
displayed.
Auto ISO sensitivity control (mode M)
A
If auto ISO sensitivity control (0245, 0331) is enabled, ISO sensitivity will
automatically be adjusted for optimal exposure at the selected shutter speed
and aperture.
❚ ❚
Long time-exposures
The camera offers two options for long time-exposures: "Bulb" and
"Time". Long time-exposures can be used for pictures of fireworks, night
scenery, the stars, or moving lights.
A 35-second exposure
shot at a shutter speed of
"Bulb" and an aperture of
f/25
Shutter
speed
Bulb
The mode selector
The shutter remains open while the shutter-release button is
held down.
Description
134