Camera Lens Angle
Please do not assume a human eyes view angle from a CCTV camera, the real coverage might be totally different than what you think it should be. Please do not tell us that this or that is not acceptable, check the following lens and angle diagram to understand the limitation of current CCTV camera technologies first please.
They cover an angle of 69.9′ in 0-6 meters effective distance. We use 4mm cameras under eave or on the way to cover a small area like an entrance, a back door, a corner of your yard or deck.
They cover and angel of 50.0′ in 5-10 meters effective distance. We use 6mm cameras for entrance and drive way.
If you prefer a wider range, use 2.8mm lens cameras. We do not have 3.6mm lens and 8mm and beyond. We focus on residential home security camera installations, we only have 2.8mm, 4mm and 6mm lens camers. The quotation is for 4mm and 6mm only. If you choose a 2.8mm camera, it cost extra $50 for each camera. The widest .25mm lens only covers a right-angle 96.4°. Human eyes are basically 180”, this is why you always think that the camera is not covering as wide as you expected.
Bullet 4mm/6mm: 1/2.5” CCD
Dome 4mm/6mm: 1/3” CCD
Lens Caculator, Field of View Calculator
Calculate Lens millimeter selection according to area size. The Field of View Calculator (or FOV) is used to help predetermine proper lens selection prior to installation. This Calculator will help with a preview to area size that is visible through the lens with entered value. Theia caculator is the one I use most, it’s quite easy to understand the calculation. Use small office as example, it’s simulation. If you are more into the numbers, use Misumi
PELCO / JVSG / Theia / Misumi / Sweeting