CCTV cameras are the surveillance system designed to monitor the surrounding environment and related activities.
Closed circuit television (CCTV) has gained a huge popularity in deterring any illegitimate or unwanted movement of an individual at a certain site.
These cameras have been used as crime deterrent by inducing a psychological fear upon the individuals. These camera lenses have become so popular that we often seem to neglect them in our common view.
Let it be market, shoping complex, hospitals, buildings, parks, traffics etc. , these CCTV camera dot each such sites where a discrepancy in security may lead to disasters.
These CCTV have been aiding the crime specialists to solve most of the mysterious cases and terrorists attack. In this article, we shall indulge ourselves in a broad analysis regarding CCTV camera lens.
Type of lenses used in CCTV cameras
The efficiency of a CCTV lens camera depends upon the type of lens used in the camera. Basically, there are two types of lens used in CCTV camera. These are:
- Fixed CCTV camera lens: These cameras have fixed viewing angle and cannot be zoomed or adjusted. The CCTV camera having such a lens is cheaper.
- Vari-focal CCTV camera lens: These lenses can be adjusted by the technician according to the area where the user wants to focus more.
The lens used in CCTV camera can be alternatively classified into two types:
Auto Iris: These lenses are receptive to the surrounding light of the area. Thus, in situation where the light seems to be inadequate, these lenses automatically enlarge their iris so as to accommodate more light and consequently the images taken are neither too bright nor too dark to see.
Similarly, in case of bright light, the iris reverses its function. These cameras are more often used for outdoor purposes.
Manual iris: these lenses do not have the features like that of the auto iris. It means that the size of the iris remains fixed irrespective of the intensity of the light impinging upon the area.
Thus, these lenses are mostly used in places which have stable light conditions (such as residence).
Use of CCTV cameras
The CCTV cameras are used at a variety of places. Some of these are enlisted below:
1) CCTV camera lenses can be used to identify the forgery done with an I-card which allows a person access to a building. These days industrial espionage, terrorism related activities and workers dishonesty have increased due to unchecked entry into the building.
This illegal entry is possible only through altering the secret code of i-d card. CCTV camera can be used to identify such entry.
2) CCTV cameras can be used to ensure security measures at both public and private sites. It creates a psychological deterring effect over the individuals.
3) CCTV cameras can be used to obtain quantitative sound pressure measurement from the sound field imaged in schlieren system. Schlieren are the optical inhomogeneity present in transparent material which are invisible to normal eyes. Study of schlieren helps in making lens free of such effects.
Benefits and Limitations of a CCTV Camera
There are numerous benefits of using a CCTV camera. Some of them are as under:
- CCTV cameras can be used to influence the employees productivity in a corporate office.
- It reduces the need for manual security like security guards who can miss to notice certain unwanted movement.
- Infrared CCTV cameras use LED technology to generate good quality images even during night.
- It saves a lot expenses incurred on the security issues of a company.
Despite of having several merits, the CCTV camera possess certain limitations. These are as under:
- The size of the camera lens and distance between the place under surveillance and CCTV mount affects the quality of image obtained by the camera.
- The installation of CCTV cameras is seen by many as a threat on one’s privacy.
How to buy a good CCTV camera
There are a large variety of camera products available in the market. Thus, before spending a single dollar, one must consider some of the features of a good CCTV camera:
- One should first of all decide the need and area where a cctv camera is to be installed.
- The buyer should consider the sensor type and size of the sensor installed in the CCTV camera. Sesnors generally come in two types-CCD and CMOS. CMOS are less expensive and less sensitive as well. On the contrary, the CCDs are more sensitive.
- Another factor to be considered is the size of the sensor. The quality of the image generated depends directly up on the size of the sensor i.e., -larger the sensor size, better is the quality of image captured.
- The camera should have a perspective corrective lens with automated diaphragm feature which allows it full brilliance view and permits the diaphragm to adjust according to the photo-electric exposure measurements performed at the body of the camera.
- It should cover a wide range and wide angle.
- The buyer must decide whether he wishes to buy the camera for day or night surveillance.
- While purchasing a CCTV camera, a buyer must check the size of the CCD chips available as it acts as a determining factor in deciding the view angle of the camera. The view angle is directly proportional to the size of the CCD (charge couple device) chip installed in the camera.
Popular CCTV camera brands
Here an attempt has been made to enlist some of the finest brands known for manufacturing quality CCTV cameras. The ones aspiring to buy a new CCTV system shall find this list very useful.
- videoSecu: It is a leading manufacturer of high quality, cost effective TV brackets and CCTV cameras. The products can also be purchased online.
- LaView: The company has several branches in US, china, Canada and philippines. The company is famous for manufacturing good security appliances.
- Foscam: The china based company is popular enough in the country known for its high quality, cost effective and comprehensive
- Zmodo: The china based company is known for manufacturing quality home safety products ranging from CCTV camera to smart home appliances. The products are highly innovative and intricately designed.
CCTV cameras have become the lifeline of any security concerns of a firm. It is due to the smartness with which the camera monitors a given site.
Thus, one must pay a lot of attention to the various buying guidelines available for purchasing a good product. This shall surely add to the safety and security parameters of a house.