Max. memory card size
The largest capacity of a memory card with which a video surveillance camera can work correctly.
High-capacity drives require fairly high processing power and may use special technologies that are not supported by all cameras. This is the reason for the limitation on the volume of supported media.
Active protection
Active protection methods implemented in the camera.
By itself, this function is intended to cause discomfort to the attacker and scare him away, as well as draw attention to the situation. It can be activated both manually and automatically (for example, by a motion sensor or a signal to the alarm input of the camera). There are two main types of active protection:
— Light (strobe). A bright light source that flashes at a rate of several flashes per second. Immediately after turning on, the strobe is capable of disorienting a person for several seconds, and even after that, the flashing light makes it difficult to coordinate and move quickly; all this can give security officers additional time to react to the situation. In addition, flashes are clearly visible not only with a direct look, but also with peripheral vision, and in the form of reflections.
— Sound (siren). A loud beep that is almost guaranteed to attract the attention of people nearby. In some models, the volume of the siren reaches 110 dB — this is comparable to the engine of an old tractor and only slightly below the pain threshold of a person.
Each of these options has its own advantages, and it is not difficult to combine them in one device. Therefore, most modern cameras with active protection use both methods described above at once.
Number of LEDs
The number of backlight LEDs (see "Design and capabilities") provided in the camera design.
Theoretically, more LEDs provide more power and, accordingly, range (see below) and efficiency
of IR illumination or LED illumination. However, in fact, such light sources can vary markedly in performance; in addition, a lot also depends on the features of the camera itself. Therefore, in fact, this indicator is a reference, and when choosing, it makes sense to pay attention to parameters that are closer to practice — in particular, the same backlight range (see below).
Illumination range
Operating range of the backlight (see "Design and capabilities") installed in the surveillance camera. This term usually means the maximum distance from the camera to the observed object, at which it is able to provide a relatively high-quality and legible image in the complete absence of other light sources. Of course, the actual backlight range may differ from the claimed one, and these differences are most often in the direction of increase (for example, due to the presence of the same additional light sources). However, if the possibility of shooting with backlight is important for you, you should focus on the claimed range.
Smart home system integration
Smart home systems that the camera is compatible with.
The general principle of all such systems is to combine various home electronics and household electrical appliances into a single complex so that all these devices can interact with each other and jointly respond to various events. As for surveillance cameras specifically, their functions in a “smart home” are mainly related to reacting to movement in the frame and broadcasting video. For example, a compatible camera can send a notification to the user’s smartphone when a motion sensor is triggered, or transmit video to a TV integrated into the home network.
Nowadays you can find different smart home platforms, the most popular are Apple HomeKit, Google Home, Amazon Alexa. However, there are other options for branded systems - as a rule, they are sold by manufacturers for their smart home and video surveillance devices. To fully work in a particular system, it is worth using cameras that have expressly stated appropriate compatibility. Also, when purchasing a compatible model, it would not hurt to clarify its specific functionality related to the “smart home”.
Number of megapixels
Camera sensor resolution in megapixels (millions of pixels).
The higher the resolution of the matrix, the higher the video resolution can be (see below), the more detailed the image is capable of providing the camera. At the same time, note that as the number of megapixels increases (without changing the size of the matrix), the size of each individual pixel decreases, which increases the likelihood of noise and deterioration in the overall image quality. Therefore, high resolution in itself is not necessarily a sign of high quality — a lot depends on other things, for example, on the size of the matrix (see above).
As for specific values, in the most modest matrices it does not exceed 1.3 MP, which corresponds to the maximum
HD resolution.
2 MP sensors allow for already Full HD resolution (usually 1920x1080 or 1600x1200),
3 MP,
4 MP,
5 MP and
6 MP are capable of better resolution, but still do not reach
4K, which is typical for 8 MP.
Video resolution
The maximum video resolution that the camera can capture.
The higher the resolution of the video, the more details you can see on it, the less details will be blurry. On the other hand, high resolution means large volumes of video materials, which, accordingly, requires capacious media for their storage and fast communication channels for broadcasting video in real time. Yes, and this indicator significantly affects the cost of the camera.
Frame rate
The maximum frame rate in the video captured by the camera.
The higher the frame rate, the clearer the image, the less noticeable blurring when moving in the frame (especially fast). On the other hand, this indicator affects the amount of information recorded during shooting, as well as the cost of the camera itself. Therefore, it makes sense to specifically look for
a video surveillance camera with high-speed shooting(45 fps and higher) only if a clear recording of fast moving objects is important to you.
Aperture
Aperture of the lens installed in the camera.
Aperture characterizes the degree of attenuation of the light flux when passing from the front lens of the lens to the matrix. It is denoted as the ratio of the diameter of the active aperture of the lens to the focal length, while the size of the active aperture is designated as f and is taken as a unit — for example, f / 1.4 or f / 2.0. Moreover, the smaller the number in the designation, the higher the aperture (in our example, the second lens will be darker than the first). And for lenses with a variable focal length (see "Focal"), the actual aperture, usually, changes with a change in focal length; for such models, either the range of aperture values, or its maximum value, can be indicated.
By itself, this parameter characterizes, first of all, how light the image taken through the lens turns out, all other things being equal. High values are important, first of all, when shooting in low light conditions: a fast lens allows you to get a fairly high-quality image without increasing the sensitivity of the matrix, which is fraught with noise and “blurring” of the picture. On the other hand, the actual quality of camera operation (including in dark conditions) also depends on many other factors — the type and size of the matrix, signal processing features, etc. Therefore, aperture in most cases is more of a reference than a practically significant parameter.
