340UIf Off is selected, the control panel and button backlights(illuminators) will only light while the power switch is rotatedtoward D. If On is selected, the backlights will remain on while thestandby timer is active (0 41). Regardless of the option selected,the backlights turn off when the shutter-release button is pressed;if On is selected, they will come back on when you lift your fingerfrom the shutter-release button. Select Off for increased batterylife.d9: LCD Illumination G button ➜ A Custom Settings menuA Button BacklightsI buttonBKT buttonRelease mode dial pointerO (Q) buttonK buttonG buttonL (Z/Q) buttonX buttonW (M) buttonJ buttonFn3 buttonS buttonT buttona buttonR buttonU buttonY button