How to choose a proper CCTV Lens for a given angle?
Different CCTV lens sizes can change the viewing angle of a security camera. Typically angle of view or CCTV lens angle can be expressed in Horizontal (HFOV), Vertical, or Diagonal. Angle of view at a given distance depends upon the focal-length of the lens and CCD Sensor size (1/6″, 1/4″, 1/3″, 1/2″ or 1″). Smaller focal lengths give a wider angle of view.In the past you would use a tables like this:
|Focal Length||1/4″, Lens Angle
||1/3″ Lens Angle
||1/3″, Width at 10m
Nowadays there is an easy way to find proper CCTV lens and proper camera locations. You can use our CCTV design tools to visualize CCTV lens angles and see how modification of any parameter affects the whole design.
When choosing the lens focal length you need to consider the purpose of the video surveillance system, general observation to detect activity/movement, or the ability of facial identification. Also dependent on the purpose is the resolution of the security camera.