What is FOV (Field of View) for Surveillance Cameras?

The field of view (FOV, also called angle of view) is the width of the scene that a camera detects on its sensor. It is determined by the focal length of the lens in relation to the sensor size. Longer lenses or smaller sensors produce narrower fields of view, while shorter lenses or larger sensors produce wider fields of view. A smaller field of view means that a camera is more “zoomed in” (to use a term that most people are familiar with). For example, a camera with a 90° horizontal field of view (HFOV) will see a 1000m wide section of a wall that is 500m in front of it. If you then adjust that camera’s HFOV to only 1°, it will fill the screen with an 8.7m wide portion of that same wall. This second “zoomed in” field of view is what customers are looking for when they want a camera that can see a long distance. They want a narrow field of view.