Nikon D6 Reference Manual page 920

Reverse Rotation
Reverse the direction of rotation of the command dials for
exposure compensation and shutter speed/aperture selection.
•
Highlight [Exposure compensation] or [Shutter speed/
aperture] and press 2 to select ( M ) or deselect ( U ).
• Press J to save changes and exit.
•
The changes apply also to the command dials for vertical
shooting.
Change Main/Sub
Reverse the roles of the main- and sub-command dials. The
changes apply also to the command dials for vertical shooting.
Option
[Exposure
setting]
[Autofocus
setting]
868 A Custom Settings: Fine-Tuning Camera Settings
If [On] is selected, the main command dial will control
aperture and the sub-command dial shutter speed. If [On
(Mode A)] is selected, the main command dial will be used
to set aperture in mode A only.
If [On] is selected, AF-area mode can be selected by
holding the AF-mode button and rotating the main
command dial, autofocus mode by holding the AF-mode
button and rotating the sub-command dial.
Description