Nikon D500 - Manual (Page 200)

174
Live View (Spot White Balance)
During live view ( 0 43, 58), white balance can be measured in a
selected area of the frame, eliminating the need to prepare a
reference object or change lenses during telephoto
photography.
1
Press the a button.
The mirror will be raised and the view through the lens will be
displayed in the camera monitor.
2
Set white balance to L (Preset manual).
Press the U button and rotate the main command dial until
L is displayed in the monitor.
U button Main command
dial
Monitor