Thanks to the ever-changing social and law and order scenario all over the world, installation of CCTV is not just restricted to commercial complexes and public places. Even households are installing state of the art CCTV, surveillance cameras to keep an eye on their premises, even when they are away from home.
The presence of CCTV setup in homes is not regarded as an act of vanity anymore. It is a necessity these days. However, before opting for a CCTV, surveillance system, it is imperative that people look for certain factors. This is needed to make sure that people do not end up purchasing a setup that falls short of the requirement, or something too expensive and sensitive, which is not needed at all. Let us look into some of these factors.
Choosing the right lens
Lens, needless to say is the most crucial component of a camera. It is the ‘eye’ of the camera, which ‘sees’ everything. Technically speaking, it is the lens, which gathers the light for its sensor. Whatever the users see or record on any DVR or other recording device, ‘comes’ via the lens. Hence, while selecting the CCTV, surveillance camera, one should put emphasis on the quality of the lens. The lens need to be powerful enough to see the faces of people clearly, and even the most minute details of objects, ranging from the number of a car to, say the mark of a cut or bruise on one’s face, irrespective of whether it is day or a dark, moonless night. Better quality lenses are more helpful than the higher output resolution. This is because the output gets restricted by the input, not matter how high it might be. On the other hand lens determines the quality of input.
Looking for the right sensor
This is another factor that needs to be taken into account. Digital sensors are not all equal. The vary mainly on two aspects, and these two aspects need to be considered while evaluating the technical specifications of a CCTV, surveillance camera. The first of them is the type of sensor, while the second one of the size of the sensor. Most of the sensors of CCTV cameras are either Complementary metal–oxide–semiconductor or CMOS or charge-coupled device or CCD. CMOS is cheaper than CCD, and it also uses lesser power than the CCD. However, the hindrance is that the CMOS are not a sensitive as the CCD cameras, and are not able to produce as clear an image as the ones with CMOS do. This can pose a serious threat when it comes to detecting minute details like identifying a face, or a number plate of a car.
The other factor that needs to be considered is the size of the sensor. The larger is the sensor, more is the amount of light than it will be able to process, and more is the amount of light the better will be the quality of the image produced. A larger sensor of a CCTV, surveillance camera not only can gather more light, in the process it gives more data to the Digital Signal Processing or DSP to work with. This is particularly helpful when less capable and weaker processors are used in low cost cameras.
Opting for the right output resolution
One of the most widespread specifications of the cameras is the number of horizontal TV resolution lines that is can deliver in its output. Or in other words, it is simply the output resolution and this needs to be considered. While it is always nice to have a camera with high output resolution, the output ultimately depends upon the DSP. Hence, the lens and the sensor must match the output resolution. Otherwise the resolution is clearly wasted.
Last but not the least, the type of CCTV, surveillance cameras also need to be taken into account, though it is a separate story altogether.