CCTV (Closed-circuit television) systems, which are also known as video surveillance, offer surveillance roles to ensure the security of people, property, and systems. These are the watchdog systems to monitor the actions and activities of people. Formerly, these were used in big buildings and firms, but nowadays they have become a significant tool for home security. Therefore, you will find so many CCTV systems for sale in the market and online.
How Does A CCTV Really Work?
The CCTV system works differently from the broadcast TV system. A direct transmission system is used to connect the camera to a screen- a monitor. In Broadcast TV system works on the electromagnetic waves, the signal is transmitted through the air and can be viewed on the TV.
In order to thoroughly understand the video surveillance specifications let’s know the key elements that combine to make a CCTV system.
The elements of a CCTV system include:
A camera
Lenses
A Monitor
Video recorders
Switchers
Camera:
A camera is the foremost and the most basic element of the CCTV system. There are two types of cameras, Analogue and IP (Internet Protocol) camera. A camera is a conventional camera used with a CCTV system. Its role is to simply transfer the data(video) through the transmission system to the monitor. On the other hand, the IP camera is an advance and digital camera that can transmit the signal over the wire to be stored in the network. IP is more preferable in current times because only watching is not enough a retention must be qualified for this system. If you have already a digital recording system you can get an analog. However, people are currently using hybrid cameras, an amalgamation of Analogue, and the IP camera.
The CCTV camera has further three main elements which complete its functionality:
1- Image Sensor
2- Lens
3- Image processing circuit.
The aperture of the lenses is responsible to capture the light waves through the lens. The circuit in the camera processes the image to transfer it via a wire.
It is important to consider the quality of the CCTV cameras; for extremely good results a camera should generate at least 1080p to 4k resolution. They should have good night vision to capture clear video even in low-intensity light.
Lenses:
The lens is the basic pioneer of a camera. It is responsible to focus light onto the imaging sensor. A CCTV camera must have a good quality lens to ensure a greater quality video. The shorter the focal length of the lens, the greater is the field of view(FoV). Field of view is the horizontal and the vertical length that the lens covers at a particular distance. lenses have three basic types, Fixed lens, Varifocal lens, and Zoom lens. A fixed lens has a set focal length, which means it has a fixed FoV. It allows the manual adjustment of the vertical length of the lens. A zoom lens is generally similar to a varifocal lens but it has a larger range of adjustments and this can be done through video management software.
Monitor:
A screen is the third and the last component of the CCTV framework. The screen makes the video, caught by the camera and communicated through the wire, to see through the unaided eyes.