The shutter speed controls how quickly or how slowly the
shutter opens and closes and affects the exposure of a picture and the clarity.
Setting a slow shutter speed is essential when taking certain types of
photographs, such as the night sky whereby you need to expose the picture long
enough to capture any image beyond just blackness. It can also be used to
demonstrate a blurred effect when something is in motion. This can be effective
for some sports photography when you can to create an impression of speed and
do not want to freeze the action. Imagine also a helicopter in flight … a
slower shutter speed will blur the rotor blades and create the impression of
movement. A fast shutter will freeze the action and might suggest the rotors
have stopped turning!
I took some photographs of motorway traffic to demonstrate
the effect of controlling the shutter speed. The shutter speed setting on my
camera is TV (time value); on some cameras it is designated by an S. For the
first picture, I set a slow shutter speed which resulted in the photograph
below. It was important that I held the camera steady to take the picture and
although I didn’t have a tripod, there was a guard rail across the bridge which
I leant on. You can see in the picture that the background image, such as the
road and trees, is sharp. The traffic meanwhile was moving while the shutter
remained open and this has created the sense of motion in the photograph. The
settings for this picture were shutter speed of 1/4 second with an aperture of
f/32 and an ISO of 400.
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I then increased the shutter speed to produce an image of
traffic frozen into place. Looking at the picture, you would assume the
vehicles are moving but there is no blur effect to confirm that this is the
case. The settings for this photograph were shutter speed of 1/500 second with
an aperture of f/5.6 and an ISO of 2000.
%2B(c).jpg)
