what is fov

Field of view (FOV) is the extent of the observable world that is seen at any given moment through an optical instrument or sensors. FOV is the open, observable area a person can see through their eyes or via an optical device, such as a camera. In photography and filmmaking, the FOV refers to what is visible through the camera lens or optical viewfinder. Changing the lens changes the FOV. To increase FOV and capture more of a scene, a wide-angle lens is used. Similarly, to decrease the FOV, a zoom lens can be used. In general, a smaller focal length lens increases the angle and the FOV. FOV is also used in remote sensing to describe the solid angle through which a detector element is sensitive to electromagnetic radiation at any one time, called instantaneous field of view or IFOV. FOV is related to two things: the focal length of the lens and the sensor size. FOV is often expressed in degrees, and it determines how big the imaged area is.