Before revision: For a normal lens , the diagonal (or horizontal or vertical) field of view can be calculated as: where is the focal length, here the sensor size and are in the same unit of length, FOV is in radians.
After revision: focused at infinityFor a normal lens , the diagonal (or horizontal or vertical) field of view can be calculated as: where is the focal length, here the sensor size and are in the same unit of length, FOV is in radians.