Nikon D300 User Manual page 166

Copying White Balance from a Photograph (d-1–d-4 Only)
Follow the steps below to copy a value for white balance from a
photograph on the memory card to a selected preset (d-1–d-4
only). Existing white balance values can not be copied to preset
d-0.
1
Select L ([Preset
manual]).
Highlight [Preset manual] in
the white balance menu
(pg. 126) and press 2.
2
Select a destination.
Highlight the destination
preset (d-1 to d-4) and press
the center of the multi selector.
r
3
Choose [Select image].
Highlight [Select image] and
press 2.
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