Contrast is a major consideration when setting
exposure. It’s also a powerful composition tool.
There are two types of contrast in photography. Tonal contrast is the term used to refer to the
range of grayscale tones between the darkest
black and whitest white in an image. A highcontrast
scene has mostly black and white with
few (sometimes no) shades in between.
A black
and white checkerboard is an excellent example.
A low-contrast scene is comprised mostly of
middle tones. Normal-contrast pictures are
in between the two extremes.
A normal-contrast
scene usually contains some elements that are
very light or white, some that are very dark or
black, and many tones or colors in between. Color contrast, the second type of contrast, refers
to the way colors interact visually in the scene.
Colors with opposite characteristics contrast
strongly when placed together.
Each color accentuates
the qualities of the other and makes the
color elements stand out dramatically. Both types of contrast are tools we can use in
our photographs to set a mood, pull the viewer
into our work, and draw the eye to the main
point of interest. They are related to exposure,
since exposure affects the way a tone or color is
recorded.
Consider how the TriCoast Photography image
in this image uses both types.
The dark setting
has generally low contrast with warm tones. The
woman’s face and her light-colored scarf and
jacket have much more contrast. Her expression,
facing directly toward the viewer, accentuates
the film noir air of mystery.
Cold colors (bluish) and warm colors (reddish)
almost always contrast. Light and dark colors
contrast against each other, as do very saturated
colors against muted shades. Harsh lighting
conditions (like bright sun or a spotlight) tend
to increase tonal contrast and color intensity,
while soft or indirect lighting reduces contrast
and increases color saturation.
Setting the exposure for this picture required
carefully arranging things so that enough light
illuminated the woman without making the
floor and background too bright. (This image
used carefully controlled lighting.) The lower
contrast in the center of the composition
increases the color saturation in the brown floor.
The exposure was 1/25th of a second at f/2.8
and an ISO of 1250. That means the scene was
10 stops darker than bright sun. The photographer
indexed the exposure on the woman. Indexing
refers to setting the Exposure Value used to ensure that
detail is held in the most important element of
the composition. Her face has more contrast
than the rest of the composition.
Normal tonal contrast and the interplay of
light and shadow can be combined with color
contrast to produce pleasing compositions. The
classical painting masters used all three to add
depth and visual texture to their works. Terrence
Karney used the same elements in this study of a
wharf in this picture:
The effect requires careful
attention to exposure, and adjusting it to control
the way highlights and shadows are recorded.
To improve your skills even more, try working
with light in the shade and even shadows.
Experiment with placing subjects next to bright
surfaces, in partial shade, and try working with
different levels of both tonal and color contrast. Another neat trick is to subtly shift the white
balance to add a little warmth (more reddishyellow)
or cooler (shift toward the blue) to the
colors in the picture. Most DSLRs have a fine tuning
control. Check the white-balance section
of the manual.
Keep the increments small, so
that the whites still look white. If you shoot
RAW files, the white balance can be changed at
any time with editing software. | 
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