Canon EOS-1D X Mark III Advanced User's Manual page 844

Multi function lock
With the power switch set to <
changed by accidentally touching <
panel.
Select the camera controls to lock by setting the switch to <
add a checkmark [ ]. Select [OK] to register the setting.
: Main Dial
The Main dial and vertical-grip Main dial will be locked.
: Quick Control Dial
The Quick control dial will be locked.
: Multi-controllers
The Multi-controller and vertical-grip Multi-controller will be locked.
: Touch control
Touch operations will be locked.
: Smart controller
The Smart controller will be locked.
Note
Attempting to use any locked camera controls (except [ Touch control]) causes
< > to appear in the viewfinder and top LCD panel and [
the Quick Control screen (
By default, the <
Custom Controls
You can assign frequently used functions to camera buttons or dials according to your
preferences for easy operations. For details, see
>, this function can prevent settings from being
>, <
) and Custom Quick Control screen (
> dial is locked when the power switch is set to <
844
>, < >, < >, or the touch-screen
Custom Controls.
>, then press < > to
] to appear on
).
>.