Section 1 The Basics
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Copyright Goodheart-Willcox Co., Inc.
On cameras using autofocus, pressing the
shutter button also activates the focusing system.
The camera focuses, and then opens the shutter
to take the picture. One advantage of this two-
step process is the ability to select a focus point
that may not be in the center of your picture and
lock the focus by pressing the button halfway
down. You can then recompose your scene and
capture it by pressing the button the rest of the
way down. A second advantage is the ability to
minimize shutter lag. In some digital cameras—
especially compacts and older models—there is
a noticeable delay between pressing the shutter
button and the actual opening of the shutter.
This is caused by the slow operation of many
autofocus systems. With the two-step method,
the already-focused camera opens the shutter
more quickly when you press the button all the
way down. This is a definite advantage when
capturing action subjects.
Shutter Release
The shutter release on modern 35 mm and
digital cameras is a button located on the top right
side of the body. To avoid moving the camera when
pressing the shutter button or lever, a shutter release
device is often used, Figure 2-10. For older cameras,
the device is a stiff wire called a cable release, or a
piece of tubing with a squeeze bulb. The wire or
air pressure physically presses the shutter release
without causing camera movement. Newer cameras
with electronic controls use a wired connection or a
radio signal to release the shutter.
If a shutter release device is not available,
the camera’s self-timer can be used to operate the
shutter without vibration. When the shutter button
is pressed, the timer performs a countdown for
a set number of seconds, and then operates the
shutter. The delay permits any vibration from
pressing the shutter release to die out.
A
B
C
Jack Klasey/Goodheart-Willcox Publisher; Courtesy of Nikon Inc., Melville, New York
Figure 2-10. A shutter release device operates the camera’s shutter without causing vibration. A—Cable releases for
older film cameras frequently offer a locking feature that holds the shutter open for time exposures. B—Wired electronic
releases connect to the camera with a cord several feet in length. C—Wireless releases using radio signals can operate
the shutter from a number of feet away.