SIGMA DP3 Merrill - Manual (Page 80)

79
WARNING !!

When the new setting is saved, the previous stored setting will be
overwritten.
LOAD THE CUSTOM MODE SETTING
Press the Mode button and set to
C1,
C2 or C3.
In custom mode, it is possible to change the above settings temporarily
(except Exposure Mode).
If the setting is changed, ★ mark will appear in
Function Display.
Return to original registered setting by doing the following.

Turn the camera off (this includes the camera turning off
automatically with the Auto Power Off function)

Press the Mode button and set to another position.