Video surveillance has become a need in most business and many private facilities. Here are some facts, about the basic characteristics of the video surveillance cameras.
The starting point for the planning of each video surveillance system is camera, and the rest of the system is projected according to the number of cameras and their features.
Type of housing
This feature refers to the physical appearance of the camera and to the housing in which they come, we can divide them into two types – box and dome cameras. Box cameras are usually elongated, and more compact box cameras.
Unlike box cameras, dome cameras use a dome casing (half-shaped ball). These cameras are more compact and less noticeable than box cameras and are also often more resistant than box cameras due to their shape.
According to the system of operation, we distinguish three types of cameras – analogue, HD-CVI / HD-TVI and network cameras.
Analog cameras are the oldest and most widespread form of video surveillance, characterized by simplicity and a very affordable price. The lack of these cameras are technical limitations in the transmission of signals that often can not meet contemporary needs.
Network cameras (IP cameras) represent the most advanced camera view. These cameras use existing computer networks, which considerably facilitate the design of installations of any length, they can work completely independently (without recorder) and what is most important to them is that they have no restrictions on the maximum resolution of the recording.
HD-CVI and HD-TVI cameras have almost the same mode of operation and represent a combination of good sides of analog and network cameras. They are designed to bring analogue video surveillance to modern needs and network surveillance, but to retain an affordable price.
The resolution of the recording is the most important feature of each camera and depends on the level of detail on the recording. The higher the resolution, the video will be clearer and have more details.
For basic video surveillance whose purpose is just insight into what is happening inside a room or in front of an object, it is often enough for a lower resolution camera, however, if it is a publicly available place, higher resolution cameras are recommended. The advantage of the higher resolution is in the level of detail, so with HD cameras it is possible to easily recognize the face, and with Full HD cameras, even reading the registration numbers from the car’s tables.
Video surveillance cameras can have different lenses, and with these lenses the focal range expressed in millimeters is the most important feature – for example, 2.8mm, 3.6mm and 6mm in fixed lenses, or 2.8 ~ 12mm in varifocal lenses.
The focal range determines the angle that the camera can cover and the magnification level (zoom), so depending on the size of the space to be covered, the corresponding lens is used.
Auto Gain Control is a technology that, in low light conditions, increases the sensitivity of the sensor to light, resulting in a brighter image.