Primary Color Correction: Tonal Range Primer - The Art and Technique of Digital Color Correction - page 3

Fig. 1.2 Note that the luminance curve is curved because a point at the midtone was pulled down. The red, green, and blue curves are all
straight lines from a black point at the bottom left to a white point at the top right.

creating a curve between the white point and the black point instead of a
simple straight line ( Figure 1.2 ).

gamma: Technically
gamma is a curve, but in
some software programs,
gamma is the label for
the midtone adjustment
slider. For all intents and
purposes, gamma and
midtone are synonymous in
color correction.

Great colorists know tricks that can enhance the perception of an
image's tonal range.

The second problem is that the image may not require an expanded
tonal range ( Figure 1.5 ) . Most shots should have a pretty wide tonal lat-
itude (range) with rich blacks and sparkling whites, but there are those
images that should not take advantage of the full tonal range. Some
examples: an igloo in a snow storm; a dark, moonlit close-up of a Navy
SEAL creeping through the underbrush; a foggy, early morning rowboat
ride; a long lens shot of a smoggy city at dusk. Each of these may only
have a partial tonal range, lacking either a deep black or bright high-
lights. However, these examples are usually the exceptions to the rules.
But they do require the colorist to consider the clues in the image itself
to determine whether anything in the image deserves to be completely
black or bright white.

The colorist must consider the clues in the image itself to determine
whether anything in the image deserves to be completely black or bright
white.