The field of view (FOV) is based on the camera & lens. Wide angle lenses are suitable for most applications due to their ability to view a large area. A 4mm wide angle lens will be able to view an area 20’ high x 26’ wide at 21’ away. As an example, a 15’ x 15’ room is shown in the diagram below. Observe that the 4mm lens (green arrows) allows better wide angle viewing coverage than the 12mm lens (red arrows). In applications where a closer view is needed (such as above a cash register or over a greater distance), an 8 or 12mm may be desired. The same camera (above) at 21’ away with a 8mm lens will have a 10’ vertical x 13’ horizontal FOV. At 21’ with a 12mm lens, the FOV will be approx 6’ vertical x 9’ horizontal. Increasing the focal length of the lens decreases the perceived distance to the viewing area. See the FOV diagram below for approximate views with different focal length lenses. |
