Figure 5-23.–Atmospheric perspective.
ground helps you to perceive the overall depth of the
scene.
Atmospheric Perspective
For all practical purposes, air is transparent. For
most photography, this is fundamentally true; however,
when pictures are made of subjects at great distances,
the air is actually less than fully transparent. This is
because air contains very fine particles of water vapor,
dust, smoke, and so on. These particles scatter light and
change its direction. The presence of scattering shows
distant subjects in pictures as having a veil or haze. The
appearance or effect of this scattering is proportional to
the distance of the objects from the viewpoint. The
greater the distance, the greater the amount of veiling or
haze (fig. 5-23). The effects of this scattering of light are
additive, but vary with atmospheric conditions.
302.305
In atmospheric perspective several factors must be
considered:
Contrast–The luminance of each object in a scene
is a direct result of the objects reflective quality and the
amount of light falling on it. When objects are far away,
light from highly reflective objects is scattered;
therefore, when viewed from a distance (or imaged on
a print), the darker portions of these distant objects do
not appear as dark and the contrast is reduced. When
there are objects both near and far from the camera, the
difference in contrast provides a perception of distance.
Brightness–The particles in air that scatter light
are also illuminated by the sun. This causes an increase
in the overall brightness of the objects seen. This
increase in luminance, coupled with a loss of contrast,
causes objects in the distance to be seen and
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