This chart represents the angle and field of view calculations for cameras with 1/3′” lenses. Note that many online lens calculators produce inaccurate angle measures for these focal lengths. Also, most 1/4″ cameras produce a significantly narrower field of view with the same focal length lens. Due to the physical nature of lens optics, the numbers listed below should be considered accurate to within + / – 3º and therefore a few feet / meters as well. They are intended as approximate guidelines to help select the appropriate lens, while each camera in fact has its own unique field of view with each specific lens. In addition, C- and CS-mount lenses typically deliver a slightly narrower field of view than our comparable board lenses. Lenses wider than roughly 5mm produce “artificially” wider fields of view than more telephoto lenses. In order to do so, the video image is slightly curved at the edges of the screen. While this artificial distortion is nominal for focal lengths between 4.3 and 3.6mm, curvature increases with wider angle lenses.