There are four types of lenses for CCTV use: Fixed Aperture, Manual Iris, Auto Iris, and Zoom. If the area you wish to observe experiences infrequent changes in light, use a manual iris lens, which can be adjusted for light only by hand. If the area the security camera will be observing experiences frequent changes in light, use an auto-iris lens. These lenses adjust to light changes automatically. Auto-iris lenses come in Video or DC, and cameras generally support one format or the other. Be sure your lens matches the camera. To perform close-ups, get a zoom lens, manual and motorized zoom lenses are easily available from most retailers.

The resolution of CCTV system is usually measured by TV lines in the field. The vertical TV lines has maximum 350 TV lines in 525-line NTSC system and is not variable. But the horizontal TV lines, which is used as the parameter of picture quality, vary depending on the quality of camera, lens, transmission and monitor.

Our security cameras have a female BNC connection. All of our Video & Power cables have two male BNC ends which connect a camera to a DVR.

CCTV has many industrial and scientific applications outside of the world of surveillance. Electron microscopy, medical imaging and robotics are all common uses of CCTV, however, the term "Closed Circuit TV" does in fact most often refer to security and surveillance camera systems. Other common forms of CCTV include live on-site video displays for special events such as various conventions, arena sports and concerts as well as pay-per-view telecasts of sporting events such as boxing and pro wrestling. Also a common user of CCTV is "in-house" television channels that broadcast to very small and specific receivers such as in hospitals, airports, racetracks, schools, malls, grocery stores, and municipal buildings.