44
Exploring Photography
• Aperture scale. This indicates the f-stop at
which the aperture is set.
Proper use of the scales is explained in
greater detail in the chapter Using a Camera. A
typical lens scale system is displayed on the
lens barrel shown in Figure 3-31.
Lens Selection
A 50 mm lens is standard or normal for
most 35 mm fi lm cameras. This lens usually
has a large aperture for low light conditions
or fast shutter speeds. The nifty fi fty, as it is
sometimes called, is an all-purpose lens when
only one lens is available. See Figure 3-32.
As discussed earlier, the 50 mm lens on a
35 mm camera creates pictures with an angle
of view close to the human eye.
Wide-Angle Lens
A wide-angle lens has a shorter focal
length than a normal lens. See Figure 3-33. At
any distance it will take in a larger area than
a normal lens.
A short focal length gives a greater angle
of view. Depth of fi eld also increases with a
shorter focal length. Wide-angle lenses are
used to photograph landscapes, buildings,
and groups of people. See Figure 3-34.
Distance
scale
Aperture scale
Depth of
field scale
Figure 3-31. Several scales are printed on the
barrels of adjustable lenses. They help the operator
in judging distance, fi nding the aperture, and
determining which objects will be in focus. The
distance scale also aids the operator using a fl ash
unit in determining fl ash-to-subject distance for
properly exposed photos.
Figure 3-32. The 50 mm lens is a great all-purpose
lens that typically has a large aperture.
Figure 3-33. A wide-angle lens has a short focal length.
A lens with a focal length of 35 mm or less is considered
a wide-angle on a 35 mm fi lm camera. (Zeiss)
17 mm
50 mm
Focal length
Focal point Sensor
Focal length
Sensor
Focal point
Normal lens (50 mm)
Wide-angle lens (17 mm)