Canon EOS 1D Software Instruction Manual page 79

Enables the electronic dial's function to be used in the reverse
direction
The electronic dial's rotational function can be reversed for selecting the AF point and
setting the shutter speed and aperture.
By matching the dial's rotation direction to the particular operation, the operation can feel
more intuitive.
When the main dial's rotational function is reversed, the horizontal AF point selection
direction does not change.
Prevents exposure compensation with the Quick Control Dial
The Quick Control Dial cannot be used to set exposure compensation.
This prevents exposure compensation from being set accidentally while the AF point is
being selected.
Enables Quick Control Dial switch to turn on/off Main Dial too
Setting the Quick Control Dial switch to <OFF> disables the Main and Quick Control Dials.
Personal Function Settings
W-73
W
4