Video surveillance is an integral part of modern security systems. The feasibility of using cameras at production facilities, shopping centers, and warehouses is not even discussed today. But as for home video surveillance, those who want to install it, as a rule, have a large number of questions: Which CCTV camera to choose? What to prefer: analogue or digital equipment? How to connect an additional video camera to an existing system? And so on. A properly equipped video surveillance system will provide: 24-hour control over the protected perimeter; workplace safety; timely response to unauthorized entry into the territory of the property; control over the work of personnel. Home surveillance cameras are not a luxury, but a price for peace of mind and security. Moreover, if you choose one equipped for specific purposes, you can fit into a very “modest” budget.
Modern video cameras are different: the principle of work; signal processing method; technical features; design as says in RIDGID manual. Traditionally, cameras are divided into analog and IT. Analog video equipment is considered obsolete, although the quality of the image obtained from cameras of this type is not inferior to the “picture” from digital devices. Despite the fact that the design of analog video cameras differs significantly from their first prototypes, their operating principle remains the same. First, the light flux enters the lens of the device, then it is amplified by the lens and transmitted to the matrix, where it is converted into an electrical signal.
For subsequent transmission of the image, it is again converted by the processor into an analog signal. Next, the “picture” appears on the monitor or is saved to the recorder. The peculiarity of an analog video signal is that it can be read from any device - the transmission principle is essentially no different from a TV signal. In digital cameras, the received signal is converted into a binary code. For further broadcasting, it does not change any more - the signal arrives at the recorder or monitor in digitized form (it can be encoded or compressed). Video signal transmission from IP cameras is carried out via a standard (so-called twisted pair) cable, fiber optic can be used.
These video cameras are worthy competitors to their digital counterparts. Camcorders with outdated specifications Video cameras of VGA, D1, CIF and 960H standards are called analog. Their disadvantages are low resolution and short data transmission distance. Otherwise, such models work the same as the new ones: broadcasting is carried out using a coaxial cable, video is saved to a hybrid or DVR recorder as says in Ricoh manual. Previously, the standard analog camera format was 625 TVL (stands for "television vertical lines") or in other words the PAL standard, which corresponds to 720x576 pixels. Today there are also models on sale: VGA – 380 TVL (approx. 640x480); D1 – 420 TVL (corresponding to 720x480); 960H – about 700 TVL (960x582). But the following types of cameras are considered completely obsolete: QCIF – used for network monitoring, the quality can be described as “there is movement”; CIF – used for observation with limited channel capacity; 2CIF - used to provide a panoramic view.
In fact, devices of this type are in no way inferior to the HD-TVI format and have the same characteristics as says in Netgear manual. The difference is that there are varieties with a resolution exceeding 1080p. What are the features of hybrid models? Hybrid (or multi-format) models are compatible with different data transmission technologies.