Canon EOS-1D X Mark III Advanced User's Manual page 836

Set shutter speed range
You can set the shutter speed range. In <
speed manually within your specified range. In <
set automatically within your specified range (except for movie recording). Select [OK] to
register the setting.
Lowest speed
Can be set in a range of 30 sec.–1/4000 sec.
Highest speed
Can be set in a range of 1/8000 sec.–15 sec.
Set aperture range
You can set the aperture value range. In <
aperture value manually within your specified range. In <
value is set automatically within your specified range. Select [OK] to register the setting.
Max. aperture
Can be set in a range of f/1.0–f/64.
Min. aperture
Can be set in a range of f/91–f/1.4.
Note
The available aperture value range varies depending on the lens's minimum and
maximum aperture value.
> or < > mode, you can set the shutter
> or < > mode, the shutter speed is
>, < >, or <
> or <
836
> mode, you can set the
> mode, the aperture