Virtually all modern camcorders include automatic-exposure and -focus controls. Automation is really handy most of the time, but it's not perfect. If you always rely on auto focus, you will inevitably see the lens "hunting" for the right setting during some shots. This can happen a lot if you shoot moving subjects. Likewise, if you are shooting over a crowd or past other objects, the camera may focus on the closer objects instead of the desired subject. If your camera has a manual-focus mode, you can avoid focus hunting by turning off auto focus.
Manual focus is pretty difficult to control if you're using a small dial or slider switch on the side of a camcorder. Try to get a camera with a focus ring around the lens; this makes manual focus much easier to control.
Know how to use the manual-exposure control (also called the iris). Exposure determines how much light is allowed to pass through the lens. The lens dilates and contracts much like the iris in a human eye. Manual exposure control allows you to fine-tune exposure if the automatic control or camcorder presets aren't providing the desired light levels. Some higher-end digital camcorders have a helpful feature called a zebra pattern. As you adjust the exposure, a striped pattern appears in the overexposed portions of the image. Overexposed areas appear as washed-out, colorless white blobs in your video image.
Although every camera is different, most camcorders have an infinite setting on the manual-focus control. In most cases, anything that is more than about ten feet away will be in focus when the lens is set to infinite. Ten feet isn't a long distance, so you may be able to resolve many focus problems by simply using the infinite setting.
Like a still camera, shutter speed for a camcorder is measured in fractions, suggesting the percentage of a second each frame is exposed. A video camera's shutter speed can affect the perception of motion for your audience.
Standard shutter speed is 1/60, which means that each frame is exposed for 1/60 of a second. Under normal, good light conditions, this is the right setting. If you'll be shooting fast motion, you may want to increase the shutter speed slightly (to 1/250 or so) to keep the action from blurring. In lower-light situations or when you want to blur fast motion (for a streaking effect that's great for filming a lighted highway at night), select a slower shutter speed if your camera supports it.
