When you use a built-in microphone, get as close to your subject as possible. Don’t forget that the distance between subject and mic changes as you walk away. If you stand 25 feet away from your subject and zoom in, you’re still 25 feet from the sound source. If you need to stay far away from your subject, consider other options.
If your camcorder has an external mic input or “active” accessory shoe, your audio options definitely increase.
There are three microphone traits that are commonly discussed:
1. How is the microphone mounted?The usual options are handheld, camera-mounted and lapel-mounted.
2. What is the coverage or directionality of the microphone?This refers to how the mic picks up sound coming from different directions. Some terms used are omnidirectional, bidirectional and shotgun.
3. Does the mic require power, either from a battery or from the camera?At first, the options may seem overwhelming; in reality, unless you purchase an expensive professional microphone, the first two traits are combined. For example, a camera-mounted microphone usually has a shotgun style of pickup; a handheld microphone has something closer to omnidirectional.
It might be easier to consider your microphone choices in the same way you’d select lenses for a camera. A shotgun microphone is like a telephoto lens. It has a narrow pickup pattern and is useful for recording more distant sounds.
A lapel or lavaliere microphone is like a macro lens, getting close to your subject and minimizing distracting background noise. Lastly, a handheld mic is similar to a standard lens, useful in many situations as long as you place the microphone close to the subject. But to carry the lens analogy a little further, recognize that with a few exceptions, none of these microphones is a zoom—the pickup pattern doesn’t change.
Next, consider how a microphone is powered. Unless your camcorder is capable of powering a microphone (check your manual), you’ll need to stick with battery-powered mics or “dynamic” mics that don’t require power.