Focusing your Digital Camera on Moving
Objects
By: Ziv Haparnas
Focusing
is an important part of shooting a good photo
alongside with composition and lighting. Focusing on
static objects is relatively easy either by manually
focusing or by using the camera auto focus feature.
Focusing is much harder when the objects are
constantly moving.
There are many techniques used by photographers in
order to take in focus sharp photos of moving
objects. Here are a few of them:
Infinite focus: When the objects are far
enough from the camera focus can be set either
manually or automatically to infinite. As long as
the moving objects stay within the infinite focus
range the photo will be sharp and clear. Although
this is applicable in some scenarios it is not
useful in many others such as shooting sport events
or air shows.
Manually correcting the focus: Using this
method the digital camera is put into manual focus
mode. Focus corrections are done manually by moving
a focus ring n the lens or pressing focus in and out
buttons. When the objects move and change their
distance from the camera the photographer manually
corrects the focus as needed. This is good in some
scenarios where the objects are moving relatively
slow and their movement is predictable. Manually
correcting the focus for objects that move very fast
or move unpredictably is not practical.
Single focus mode: When using this method the
digital camera is put into single focus mode. The
camera will automatically focus on the object when
the shutter button is pressed. This method can be
combined with the manual focus method. The
photographer manually focuses on the object and the
camera is executing the final focus fixes when the
shutter is pressed and the photo is taken. This
method is limited to either slow moving objects or
high end fast focusing cameras. Focusing is a
mechanical process and takes time. If the camera
takes too long to focus by the time it is focused on
a fast moving object the object will move and the
photo will not be in focus anymore.
Continuous
auto focus: In this method the camera is put
into continuous focus mode. Once the shutter button
is pressed and as long as it is held half way down
the camera continuously focuses on the objects in
the photo. In this method the camera continuously
corrects the focus as the objects distance from the
camera changes. This method is very useful. Even if
the object is moving fast the camera can track its
movement and continuously correct the focus. By
holding the shutter button half way down and
continuously moving the camera to follow the moving
object the camera will continuously keep the object
in focus. When you are ready to shoot the photo
simply press the shutter button all the way down.
One drawback of this method is high power
consumption as the camera continuously corrects the
focus it uses the power hungry motors in the lens in
order to move the optical components.
Taking good photos of moving objects is not easy.
It requires practice and experience. In addition
to making sure that the objects are in focus you
have to continuously consider the composition, the
changing lighting conditions, shutter speed to
freeze or capture movement, the changing zoon and
more. Go and practice shooting a lot of moving
objects photos. By shooting a lot of photos in
different situations you will grow the instincts
that will make all these processes and
considerations an unconscious automatic process.
Ziv Haparnas is a technology veteran and writes
about practical technology and science issues. This
article can be reprinted and used as long as the
resource box including the backlink is included. You
can find more information about photo album printing
and photography in general on
http://www.printrates.com - a site dedicated to
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