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Capturing images...
CAPturing imAgeS
Henri Cartier-Bresson is famous for his photographs that capture that “deci-
sive moment” when unrelated actions intersect in a single instant that makes
an arresting photograph. His eye-hand coordination was unrivaled, and he
was able to get the results he did because he was always ready. There was
never any fumbling with controls or lost opportunities. Most digital cameras
have automatic exposure and focus systems that free you from the worry
about controls. However, these cameras have other problems that make deci-
sive moments hard to capture. Many of these problems have been eliminated
on expensive cameras, but remain on less expensive ones.
One of the things that has driven many photographers to distraction is the
delay between pressing the shutter button and the camera actually taking the
picture. This and other delays built into digital cameras affect your ability to
capture fleeting expressions or respond to fast action when taking pictures.- The startup time is how long it takes for you to take a photo after turning
on the camera. Cameras used to take a long time to do this, but now many
start up almost instantly. - The shutter-lag time is the delay you experience between pressing the
shutter button and actually capturing an image. This delay occurs because it
takes the camera time to clear the image sensor, set white balance to correct
for color, set the exposure, and focus the image before it fires the flash (if it’s
needed) and take the picture. The best cameras now have almost no lag. - The processing delay occurs as an image is processed and stored, espe-
cially when using noise reduction. This delay has been dramatically reduced
by the addition of internal memory, called a “buffer.” Images are temporar-
ily stored in the buffer while awaiting processing because they can be stored
there faster then they can be stored on a memory card. You can continue
shooting until the buffer fills, and then resume when some images have been
transferred from it to the memory card. - A flash recycle delay occurs after taking a series of flash photos one after
another. While the flash is recharging you often can’t take a picture, or if you
can, it comes out dark. In either case you need to wait for the flash to re-
charge and try again. - Viewfinder blackout. When you take a picture with an SLR, its mirror
swings up so light can strike the image sensor. While it’s up, you can’t see
through the viewfinder. This viewfinder blackout should be as short as pos-
sible.
All of these delays affect how quickly you can get off the first shot or capture
a series of photos one after another (often referred to as shot-to-shot time). If
the delays are too long, you may miss a picture.
To reduce delays when capturing action shots, compose the image and press
the shutter button halfway down to lock focus and exposure. Continue to hold
it down until the action you anticipated happens and then press it rest of the
way down to take the picture. (This does drain batteries faster.) The camera
shoots immediately because focus and exposure have already been calculated.
On some cameras you can also press the shutter button all the way down in
one action, but there will be a delay before the photo is taken and it may be
out of focus.
Responsiveness is
most important when
photographing moving
subjects.
When anticipating
action, compose the
scene and focus the
camera. When the
action happens you
can then capture it
instantly.