Nikon D3300 - Manual (Page 151)

131 P, S, A, and M Modes
5
Measure white balance.
Before the indicators stop flashing,
frame the reference object so that it
fills the viewfinder and press the
shutter-release button all the way down. No photograph will
be recorded; white balance can be measured accurately even
when the camera is not in focus.
6
Check the results.
If the camera was able to measure a
value for white balance, the message
shown at right will be displayed and
a will flash in the viewfinder for
about eight seconds before the
camera returns to shooting mode. To
return to shooting mode immediately,
press the shutter-release button
halfway.
If lighting is too dark or too bright, the
camera may be unable to measure
white balance. A message will appear
in the information display and a
flashing
b a will appear in the
viewfinder for about eight seconds.
Return to Step 5 and measure white
balance again.