CURRENT HD DSLRS lack the professional XLR audio input of dedicated video camcorders, but most video-capable still cameras do include a 3.5mm stereo jack (also called an 1/8-inch mini-jack). Although most high-end mics feature XLR plugs, you can find plenty of microphones with stereo jacks and, by plugging in, you'll gain far more control over incoming audio. (You also might look for XLR-to-mini-jack connectors.) Here, we classify microphone types by their pickup patterns. Seen in diagram form, the various patterns show how the mic will capture sound from different directions. To choose the appropriate microphone for your shoot, first consider what you're going to record.
Omnidirectional microphones, as the name implies, pick up sounds from all directions equally. For filmmaking, omnidirectionals normally aren't a good choice because they pick up too much unwanted sound. Of the directional types, cardioid mics are popular for capturing dialogue and doing interviews. Their distinctive pickup pattern is roughly heart-shaped—hence, the name—which indicates that they're most sensitive to sound that's on-axis in front, becoming progressively less sensitive to peripheral sound and, ultimately, least sensitive to sound that comes from directly behind.
Hypercardioid, or shotgun, micro-phones have a pickup pattern that looks like an exaggerated, forward-facing cardioid shape; these models are among the most popular for HD DSLR shooters. Shotguns capture audio in a relatively narrow angle of view that's directly on-axis. An inexpensive shotgun mic represents a good choice for most people who are starting to experiment with filmmaking or just recording motion clips.
You may have heard that lavalier mics are a necessity for capturing motion shots that involve people talking. Lavaliers are distinguished by their miniature size, not necessarily their pickup pattern. The most popular lavaliers are omnidirectional and are frequently hidden within folds of a garment, such as behind a tie, scarf or suit-coat lapel. You need to be aware of rustling noises and keeping wires and wireless transmitters out of the shot. Lavs are also available with other sound patterns.