A shotgun microphone is a type of directional microphone commonly used in television and movie production; it is used to process or amplify sounds directly in front of the microphone rather than sounds from the sides or ambient sounds in a room. The narrow shape of a shotgun microphone, and its orientation when mounted on a camera, makes it appear shotgun-like, hence the name. The microphone can pick up some sound to the left, right, and rear of the mic, but it is specifically designed to pick up the most sound from the front of the microphone.
The category in which a shotgun microphone falls is the directional microphone, meaning the mic is best used to pick up sounds from a certain direction. Omnidirectional microphones, such as condenser microphones, are better used for picking up sounds from many directions and condensing them into smaller signals for processing. Condenser microphones are most useful in controlled environments such as studio spaces, while a shotgun microphone is best used on assignment in different locations, particularly in noisy locations. A person standing in front of the microphone will still be able to be heard despite a significant amount of ambient noise.
A condenser microphone can be designed to act as a shotgun microphone as well. Condenser microphones are useful for picking up quieter sounds easily by using a certain type of diaphragm that vibrates when sound waves strike it. This method can be used in a shotgun microphone, and that microphone can be used to pick up sounds at a longer distance. The microphone may still be directional, but it will be able to pick up more sounds as well as sounds from a greater distance with better clarity.
Like many other types of microphones, a shotgun microphone is often used in conjunction with a windscreen or pop filter. These devices are made of thin materials that hang over or in front of the microphone to prevent air from striking the diaphragm, causing a popping sound or loud wind sound. Shotgun mics are often mounted on television cameras that are taken out on assignment, so windscreens help prevent the microphone from being inundated with loud, annoying sounds caused by wind or the cameraman's movement. The mic can be taken off the camera itself, though it is usually mounted to the camera for ease of use. A cable must be used to connect the microphone to the camera so the sounds can be recorded.