Camera model
A model of pointed cameras supplied with a video surveillance kit. Knowing this data, you can find detailed information on the cameras and clarify their characteristics. Also, if you buy additional cameras of the same model, you don't have to worry about compatibility.
Martix type
The type of matrices used in pointed cameras.
— CMOS. Also known as CMOS. Matrices of this type have good speed, small size, low power consumption and lower cost than CCD. On the other hand, the image quality of CMOS matrices is somewhat worse, and the noise is noticeably higher. However, these shortcomings can be corrected with the help of constructive tricks, and the technology itself is constantly being improved. Therefore, today CMOS matrices can be found both in inexpensive and in fairly advanced cameras; the actual quality of the sensor usually depends on the price category of the camera.
— CCD. Another well-known name is CCD. Compared to CMOS, such matrices are much more expensive and thicker, but they have lower noise levels and noticeably improve image quality. Of the practical disadvantages of CCD, it is worth noting that it is difficult to properly process point light sources; however, in many cameras, this moment is compensated to one degree or another by special technologies. Matrices of this type are typical for cameras of the middle and top levels.
— DIS. The main feature of DIS matrices is the presence of a built-in image processor in the sensor itself. This allows you to achieve good image quality with small dimensions and low cost of the cameras themselves. In addition, DIS matrices are resistant to low temperatures, which makes them especially suitable for outdoor applications.
Matrix size
The physical size of the sensor in the pointed cameras is diagonally, in inches (fractions of an inch).
The larger the sensor, the less prone it is to noise, the better image quality it can provide, and the better it is suited to low light conditions. This is due to the fact that each individual pixel gets more light, because. on a large matrix and individual dots are larger. On the other hand, large matrices are more expensive.
Resolution
Resolution of the analogue video output from the included pointed cameras. In the most popular modern analogue video formats — PAL and NTSC — the vertical frame size (number of lines) is standard. Therefore, the resolution of such a video is indicated by only one digit — the number of TV lines (TVL), corresponding to the horizontal size.
Higher resolution improves the visibility of fine details; however, it is worth remembering that in order to fully view such a video, you will also need a screen with the appropriate characteristics. And this parameter also significantly affects the cost of the camera.
Horizontal viewing angle
The viewing angle of the directional cameras supplied as standard is horizontal.
Wide viewing angles allow you to cover a large area; this is especially important given that directional cameras are often made stationary. On the other hand, all other things being equal, a larger viewing angle will mean a lower degree of magnification - objects will look smaller, detail will be worse. Therefore, when choosing according to this parameter, you should proceed from what is more important - a wide field of view or “range”.
RCA audio input
The number of
RCA audio inputs provided in the design of the complete recorder.
The presence of such connectors allows the recorder to receive an analogue audio signal from cameras that have the ability to capture sound, or from separately made microphones. It is worth looking for a set with such capabilities in cases where it is critical to record not only the picture, but also the sound during observation. Note that the number of RCA inputs may correspond to the number of BNC connectors (see above), but may be less.
Recording resolution
The maximum frame resolution in which the complete recorder can record video if all video channels are involved in operation. In fact, we are talking about the highest resolution in maximum load mode; if some channels are idle, some models allow higher resolutions. However, it is customary to indicate this parameter in the specifications - it most accurately characterizes the capabilities of the device.
As for the resolution itself, the higher it is, the more detailed the image is; on the other hand, such video requires significant processing power and capacious storage drives, which affects the final cost of the equipment.
Popular maximum frame resolutions in which modern recorders record:
HD (720),
Full HD (1080),
Quad HD,
Ultra HD (4K).
Frame rate
The highest frame rate at which the complete recorder can record at full load when all video channels are used. In other words, this is the guaranteed maximum frame rate that can be achieved at any load level (with some channels idle, the number of frames per second may be higher, but not necessarily).
The higher the frame rate, the better fast movement will be captured, the less blurry objects in such scenes will turn out. On the other hand, this indicator directly affects the cost of equipment and the amount of memory occupied by the footage. For video surveillance systems, an indicator of 24 fps is currently considered the minimum necessary, 50 – 60 fps is not bad, and in the most advanced registrars this number can reach 120 fps.
Video compression format
The format in which the kit recorder records digital video.
This setting determines the codecs required to view content on external devices. When viewing on a computer with codecs, there are usually no problems: their set in modern operating systems is quite extensive, and the missing modules, usually, are easily found and installed via the Internet. But if you plan to view video materials through a media centre, a TV with direct playback via USB, etc. — It is worth making sure that this device supports the appropriate compression formats.
Technical details on different standards can be found in special sources.
