Nikon D300 Complete Manual page 487

V1.02
Page 2: (Only appears if you've set RGB histogram to
appear using Display mode). The folder number and file
number appear just below the minimized image (100-25 in
this example), while overall (white) and individual channel
histograms (red, green, and blue) appear to the right and
below it. Here's another wrinkle: the RGB, R, G, and B
indicators in the lower left blink to indicate which channel (or
channels) are being shown as overexposed, just like in
Highlights (if none are highlighted, then Highlights aren't
being shown). To show the Highlight indicator and move it
between channels on this page, hold the Thumbnail/Zoom
Out (h±) button and press the < or > key on the Direction
pad. The next time you pull up an image and look at this page
of information for it, the highlights setting will be
remembered.
Page 3: (Only appears if you've set Data to appear using
Display mode). Metering method, shutter speed, aperture,
exposure mode, ISO, exposure compensation, focal length,
lens, autofocus method, VR, and flash mode are displayed
over the image.
Thom Hogan's Complete Guide to the Nikon D300 Page 487