V1.02
Thom Hogan’s Complete Guide to the Nikon D300
Page 272
picture, and a histogram for each of the Red, Blue, and Green
channels is placed along the right side.
This example shows why the channel histograms are important. Look at the
red histogram. Note the spike up the right side? That means that the red
channel is fully saturated and blowing out (probably that red roof). Yet the
luminance histogram (white) doesn’t show any blowout! Here’s the same
image properly exposed: