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.

Camera Resolution

The industry of CCD video camera sensor uses pixels (picture elements) as its quality parameter. Medium resolution of B/W camera in EIA system is 510 horizontal pixels by 492 vertical pixels and is equivalent to 380 TV lines. High resolution is 768(H) x 492(V) pixels and equivalent to 570 TV lines. Color camera's medium resolution means 330TV lines and high resolution needs more than 460 TV lines.

Monitor Resolution

The monitors in NTSC system have 525 vertical scanning lines regardless of their size. The horizontal 700 TV lines of B/W monitors represents medium level and more than 900 TV lines means high resolution in EIA system. The color monitor's horizontal resolution of 300 TV lines means medium quality and that of more than 450 TV lines means high resolution.

To maximize the system's resolution, it is recommended to choose a monitor which has better resolution than that of the camera.