NEW - Ken Gilbert

fiMT. MORAN, GRAND TETON NATIONAL PARK, WY Composed mostly of
midtones, this scene required a histogram curve in the middle of the graph. Canon EOS
5D with 24–105mm f/4L Canon EF lens on tripod; 4 sec at f/16, ISO 100.
dark areas are underexposed. On
the right, you’ve lost highlight detail
due to overexposure. Adjust your
settings accordingly and keep checking
the histogram until both sides are
contained on the scale.
Your camera’s sensor, though, can
detect only a limited range of tones
between pure black and pure white.
This dynamic range is around 6 to 8
stops of light for most DSLRs, enough
to capture both the shadow and
highlight detail in most scenes. But if
the contrast range of the scene you’re
shooting exceeds the sensor’s dynamic
range, you may get clipping in both
the dark and bright areas—adjusting
exposure may help bring one tail of the
histogram into range, but not both.
How do you fi x this? One way is to
sacrifi ce detail in either the shadows
or the highlights. (Keep in mind that
most viewers will generally be more
tolerant of blocked-up shadows than
blown-out highlights.) Another is to
reduce the contrast range by using a
hard-edge or graduated split neutraldensity
fi lter to mask off the brightest
portion of the scene, such as sky above
a shadowed foreground.
If you don’t have a fi lter, or if the
scene has no straight dividing line,
you can blend multiple exposures,
commonly called high dynamic
range (HDR) imaging. Blend them
together using software such as Adobe
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