CCTV stands for closed circuit television, In Closed Circuit TV (CCTV), the picture is viewed or recorded, but not broadcast, and it is a visual surveillance technology designed for monitoring a variety of environments and activities. CCTV systems typically involve a fixed (or “dedicated”) communications link between cameras and monitors. It was initially developed as a means of security for banks however, today it has been developed to the point where it is simple and inexpensive enough to be used with Home Security Systems, and for everyday surveillance. CCTV has many industrial and scientific applications, including electron microscopy, medical imaging and robotics, but the term “closed circuit TV” refers most often to security and surveillance camera systems.
Uses of CCTV:
1. Detecting crimes or solving a crime that’s already occurred.
The use of CCTV cameras in crime prevention is well known. The security of banks and other government establishments in the present day and age is incomplete without the installation of CCTV camera systems. They can be used to keep a record of things and in instances when there is a crime, the sequence of events can be studied later on. Quite naturally, these cameras are put in place in city centers, shopping malls, and gas stations where there are more chances of such untoward incidents happening. Although CCTV is used in crime prevention but no evidence to really back that up, for instance about 20 percent of the world’s CCTV cameras are implanted in the UK and about 78 percent of the governments crime prevention budget was spent on CCTV cameras during the 1990’s which is a huge amount of money on something where there’s no proof that it has actually been effective.
CCTV is most commonly used for surveillance, CCTV networks can be used in hospitals to allow nurses to keep an eye on multiple patients at the same time, and they can also be used to monitor traffic at busy intersections.
3. Improving the safety of public transportation systems.
The installation of these cameras on strategic positions helps authorities to be doubly sure that nobody is near the doors when a train is starting, for instance.
4. Recording events.
To be used as an evidence and to inform investigations. For instance, on the boundaries of the Parliamentary estate, police on patrol alert CCTV operators of incidents via radio links. CCTV operators then record incidents as they unfold.
5. Other common forms of CCTV.
These forms 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. The latest use of CCTV cameras is in cars and vehicles to assist drivers in parking and reversing.
What are the different types of CCTV lenses, and how does one choose which lens to use?
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.
A drawback of CCTV;
The widespread availability and use of CCTV cameras has a draw back in that they may be used by criminals to gather vital data about other innocent victims. Secretly installed cameras around ATM machines can track the pin number of an unsuspecting user and transmit the data wirelessly to the criminal. There is also the possibility that hidden cameras might be used by perverts to pry on their victims remotely or record them in compromising positions and use this data to black mail or extort money.
Your class now is over and now all of your questions are answered. CCTV has many advantages and a few disadvantages because of that, it is commonly used all over the world, I believe CCTV 101 tells you why.