Sometimes it pays to be a control freak
Automation is nice. Heat sensing microwaves that can tell how long to heat leftovers, say, are very convenient. But sometimes you need to override the automatic settings to cook things just the way you like them.
The same holds true for camcorders. While most camcorders automatically adjust the focus, audio levels, shutter speed and iris to ambient conditions, your videos might look better if you override some of your unit's features and take control of your shots.
But with everything set automatically, why bother? Well, you may encounter situations where your camcorder, for all its technological wizardry, just can't make heads or tails of what's going on. Or you may want to create a visual effect that goes against the grain of your camcorder's automatic sensibilities.
In any case, taking control of your camcorder's functions is simple enough.
Generally speaking, your camcorder determines focus by finding a well-defined object in your frame--typically whatever is in the center of your shot--and using that as a reference point for deciding how to focus.
Regardless of how handy autofocus can be, there are situations when your camcorder finds it difficult to locate the subject of your shot. When there's not enough light, perhaps at night or in a dimly lit room, objects tend to blend into one gray mass as far as the camcorder can tell.
Your camcorder, desperately trying to locate the subject of the shot, goes in and out of focus rapidly. With manual control, you can use your eye, which is infinitely more sensitive to light than your camcorder, to focus the shot instead.
Manual focus allows you to add certain effects to your video. For example, there is a manual focus technique called rack focus that camera operators use to bring the foreground and background alternatively in and out of focus. Racking focus allows you to direct the viewers' attention within a given shot by focusing on different objects successively, each time blurring the other parts of the shot.
You've probably seen this technique in a movie or television program: a close-up shot of the telephone, sitting on the edge of the desk, ringing off the hook. The background is blurred just enough to obscure it. The camera operator then slowly shifts focus from the telephone to the background where a man sits in an easy chair. As the man comes into focus, the phone blurs.
You may want to blur your shot as a segue from one segment to another. You can create a unique transition from shot to shot by ending and beginning each shot out of focus. One gray blur looks pretty much like another; by blurring your shots this way, you can cut from shot to shot creating an interesting in-camera transition effect.
How do you switch from auto to manual focus? Most units have a button somewhere on the camcorder that will toggle autofocus on and off. You'll have to consult your manual for the specifics regarding your camcorder.
The convenient thing about autofocus is that when you turn it back on, your shot will automatically focus itself. This is useful if, as I described above, you want to begin your shot blurry and rapidly bring it back into focus. Use manual focus to blur your subject first, then after a few seconds of recording the blurred image, turn the autofocus back on again. Your subject will come into sharp focus as your camcorder takes over for you.
Many camcorders allow you to adjust the shutter speed and iris control. In conventional photography, shutter speed refers to the increment of time it takes for the camera's shutter to open and close, effectively "taking a picture." This usually takes only a fraction of a second, perhaps 1/60 of a second.
When photographing objects that are stationary or relatively slow moving, 1/60 of a second is more than fast enough for the shutter to open and close. For really fast moving action, though--the kind that happens faster than 1/60 of a second--you run the risk of getting "motion blur." Simply put, motion blur is a blurring of your subject that occurs when your subject moves during the time the shutter of your camera is open. To avoid motion blur, your camera's shutter must open and close faster than your subject can move.
For the videographer, shutter speed is simply a concept; there isn't a shutter inside of your camcorder per se. Instead, shutter speed refers to the length of time the CCD is allowed to gather light. Because a camcorder is gathering light a minimum of 60 times a second, 1/60th of a second is the slowest shutter speed most camcorders can use. Many camcorders allow the CCD to be open for less time though, with shutter speeds as fast as 1/10,000th of a second.
But what if you want to capture some of your video as a still image? Maybe your son's a sprint car driver and you want to post pictures of his latest race on your Web site. When you play back your recording of the race, all those cars whizzing by you may look just fine. Try to capture a still of your son at the checkered flag, however, and you may only be able to get a blur. Adapting your motion pictures to the world of still imagery makes shutter speed more important.
Many of today's camcorders have a high-speed shutter option. This option effectively overrides your camcorder's automatic shutter settings, which are usually somewhere in the 1/60 to 1/250 of a second range, and allows you to increase the shutter speed.
On most camcorders, you will find a button to press or menu option to access to increase your camcorder's shutter speed. These increments vary by unit, but usually your shutter speed will double with each push of the button until your camcorder reaches its fastest shutter speed. As always, consult your manual for the specifics concerning your particular unit.
Before you start manually adjusting your shutter, though, you should know that by increasing shutter speed you also limit the amount of light you let into the camcorder. The faster the shutter setting, the less time there is for light to enter. As such, when using a high shutter speed, make sure you are shooting with plenty of light, either outdoors on a bright day or with some kind of auxiliarly light source. If you don't, you'll avoid motion blur, but you'll also have a shot too dark to see. For more detail on this topic, see "The Ins and Outs of High-speed Shutters" by Joe McCleskey in the January, 1999 issue of Videomaker.
The subject of light entering the camera leads to a discussion of iris control. You know about the iris in your eyeball; it's the colored muscle that controls the amount of light entering the eye.
The iris in your eye is always in automatic mode. It constantly regulates the amount of light flowing in, allowing you to see properly. While your camcorder's iris control mimics this function fairly well, there are times when you'll want to manually let more light into the unit.
Suppose you are shooting a subject that is considerably darker than its surroundings. Under ambient light conditions, the subject may be difficult to see. You might be shooting an object against a very bright background--perhaps someone standing indoors in front of a window. This would make your subject appear to be little more than a silhouette. By opening the iris manually, however, you can counter the effects of the overly-bright background and make the subject visible again.
What about shooting at a high shutter speed? The higher the shutter speed, the darker the shot. Opening the iris may compensate for the decreased brightness of your shot.
When it's simply too dark to see clearly you can try opening the iris to maximize the amount of light entering the camcorder.
But Wait, There's More
Manual control of your camcorder doesn't stop with the aforementioned items. Some high-end camcorders allow you to zoom manually--without the assistance of the unit's servo motors. This capability allows you to vary the speed of your zoom dramatically. Audio levels can even be adjusted in some units, so that you can "pump up the volume" on the fly, if necessary. Many units allow you to color calibrate them manually by pointing the camcorder at a white object and using the manual white balance button.
The most important thing to remember about manual controls, however, is that they are available to you when you need them. In most home video scenarios, you'll find your camcorder's automatic settings work just fine. For those times when you must jump into the captain's chair, though, don't be afraid to take the controls.