Nikon D300 Complete Manual page 331

6. Navigate to Select image and press the > key on the
Direction pad to select it.
7. Navigate to the image you want to use and press the
center of the Direction pad to select it.
8. At this point you can continue and name this white
balance by pressing the center of the Direction pad
and selecting Edit comment or you can just press the
OK button to complete the setting.
Note: You can only copy white balance from an image taken with
a D300. Curiously, the D300 will sometimes show you
images from other cameras, but you'll get an error message
(Can only use photo taken with D300) if you select one.
You may wonder why you'd want to copy white balance from
an existing picture on the card. Let me give you an example
of when this is handy. Let's say you were assigned to shoot a
wedding. During a relatively short period of time you need to
take pictures in the wings of the church, at the altar during the
ceremony, out on the steps of church, and in several different
rooms at the reception. Let's assume further that all these
locations have tricky lighting conditions (any wedding
Thom Hogan's Complete Guide to the Nikon D300
V1.02
Page 331