Feature: Capturing Action With Your Digital Camera
Everybody likes motion--even our vocabulary makes that clear. We love "movers and shakers," for instance. We describe fun friends as having "animated personalities;" the good stuff is always "up and coming." Slowpokes, like sloths and snails, have a somewhat less glowing reputation. So if motion is such a good thing, perhaps we should put a little into our photographs.
There are any number of ways to infuse your pictures with activity. For the next few weeks, let's talk about how to capture motion with your digital camera, and even how to infuse some faux motion into a picture on your PC.
Prefocusing Is Essential
If digital cameras have one characteristic that's disappointing to folks coming from film, it's the fact that they have a short delay--sometimes called a "lag"--between when you press the shutter release and when the picture is taken. People complain to me about this all the time, and unfortunately there's not a lot you can do to eliminate it entirely. But there are a few things you can do to minimize it.
It helps to know what causes shutter lag to begin with. When you press the shutter release, your camera has to do a lot of things, like focus, measure and set the exposure, adjust the white balance, and a handful of other less-interesting housecleaning tasks. You can shorten the delay by doing some of those things in advance. For example, if you can, take your digital camera out of auto-white balance mode and use an appropriate preset for the lighting you're in.
Most importantly, when you sense a picture opportunity coming up, you should press the shutter down halfway to lock in the focus, then wait for the right moment to take the shot. Then press the shutter the rest of the way to catch the action with a much shorter delay.
A side note: Are you shopping for a new digital camera? Try it out to see exactly how good (or bad) the shutter lag is. In my opinion, shutter lag is one of the most important specs, but it's rarely mentioned on the box. Try taking some pictures in the store to see whether the lag is short, like a tenth of a second, or long, like a half second or more.
Dial "A" for Action
Now that you know how to reduce shutter lag, it helps to know what camera mode is right to capture the action. Sometimes it's obvious: If your camera has a mode called action or sports, that's probably a good choice. Cameras usually indicate action mode with a descriptive icon, such as a running figure. This mode configures your camera to use the fastest available shutter speed, which accomplishes two things: a fast shutter stops action better than a slow shutter (which might allow the subject to blur) and it tends to make the depth of field short, which means the background will be out of focus so the subject comes to the fore.
Action mode isn't always the best choice, though. And depending upon the camera, it may not even be available. Shutter priority mode is a slightly more advanced alternative. When you switch to shutter priority, you dial in the shutter speed while the camera automatically picks the aperture setting to give you the right exposure.
Since you'll often be taking one-chance shots that can't be repeated, however, you need to be careful when using this mode. Some digital cameras will not let you choose a shutter speed that will under- or overexpose the scene--but many others will allow it, displaying a subtle warning in the viewfinder. If you pick a shutter speed that will create a bad exposure, usually the shutter speed or the aperture value will flash, telling you that something is wrong.
To get a good exposure, you need to find out how your camera works and keep an eye on the display. Want to test your camera? Set it on shutter priority and try to take a picture indoors. You should have no trouble setting a slow shutter speed like 1/2 second. Slowly change the shutter speed to 1/15, 1/30, and faster, keeping an eye on the display. When the numbers start to flash, you've gone too far and need to back off to a slower speed.
Here's a handy tip: Since you'll need to shoot action with a very high shutter speed, the tendency when using shutter priority mode is to underexpose the picture. The good news is that you can safely underexpose most digital pictures a little bit without noticeably degrading image quality.
Next week, we'll continue our look at action photo techniques.