Comparison Reolink Video Doorbell WiFi vs IMILAB Smart Wireless Video Doorbell

A method for connecting the calling panel to an intercom or other similar device.

All modern connection types can be divided into three main categories: wired analog(2, 3 or 4 wires), wired digital(network - LAN) and wireless(Wi-Fi). Moreover, the last two formats can be combined in one device. Here is a more detailed description of each of these options:

— 2-wire. The simplest type of wired analog connection; used in select low-cost audio panels (see "Type").

— 3-wire. A very rare option: in simple analog devices, manufacturers often provide 2 wires, and in advanced ones - 4.

— 4-wire. The most functional and, as a result, the most popular type of analog wired connection. Suitable even for high-end video panels, although in fact it is found in all categories of devices - from budget to high-end.

— RJ-45. Connection via an RJ-45 connector via an Ethernet network cable (“twisted pair”). This option is convenient because the calling panel can be connected to a local computer network, which provides several advantages. Firstly, the ability to access the panel can be configured on any computer or gadget within the network. Secondly, many similar models can work without intercoms and other special equipment - through an application on a computer/gadget. Thirdly, laying a network cable from the panel to the router/switch i...s often simpler than organizing an analog connection (for example, 4 wires - see above). Fourthly, the number of panels and other special equipment within the local area can be almost any - it is quite possible to combine, for example, all the calling panels of an apartment building or a large office center into one network. And if you wish, you can even set up access to the calling panel via the Internet, which will make it possible to communicate with visitors and control access to the premises, even when you are not on site.

- Wi-Fi. Connection via Wi-Fi wireless standard. This option provides almost all the same capabilities as the RJ-45 described above, but has certain differences. The most noticeable of them is the absence of a wire, which greatly simplifies installation and connection. At the same time, even relatively limited Wi-Fi devices have the power to operate reliably at a distance of a couple of tens of meters or through 1 - 2 medium-thick walls. The second nuance is the possibility of direct communication with a smartphone, tablet, etc., without using computer networks; This possibility should be clarified separately, but it is in this format, for example, that video calls work (see “Type”).

— RJ-45 / Wi-Fi. Supports the two connection methods described above at once. Such panels turn out to be as universal as possible, however, in practice, the ability to freely choose between LAN and Wi-Fi is extremely rarely required, and it significantly affects the cost. Therefore, this option was not particularly widespread.

Diagonal size of the surveillance camera matrix. This parameter is traditionally indicated in inches and fractions of an inch.

With the same type (see above) and the number of megapixels (see below), larger sensors are considered more advanced. This is due to the fact that a large sensor size means a larger area of each individual pixel — and this, in turn, increases the amount of light falling on each pixel, has a positive effect on light sensitivity and reduces noise. Large sensors are especially important for working in low light conditions, including with IR illumination (see "Design and capabilities"). However, for calling panels, matrices are mainly limited to 1/4" and 1/3" sizes. Other options are much less common.

The number of megapixels in the camera sensor, in other words, its resolution. A megapixel is one million light-sensitive dots (pixels) that make up an image; the resolution of modern matrices is very high, so it is more convenient to use just this method of designation. However, for call panels, the values are 1 MP, 1.3 MP and 2 MP. More advanced options are extremely rare.

The higher the resolution of the matrix, the higher the video resolution can be (see below), the more detailed the image can be provided by the door panel 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).

The maximum video resolution that the call panel camera can provide.

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 fast communication channels, and this indicator significantly affects the cost of the device.

Video compression format (codec) used by the door panel camera.

In practice, this information is important mainly for assessing compatibility with other special equipment, as well as when viewing captured video on household media players. This point is not important for interaction with a computer: most modern operating systems have extensive sets of built-in codecs, and if necessary, additional codecs can be installed separately. However, different video compression formats also have some specific features, here they are:

- H.263. The oldest of the codecs widely used in digital cameras of calling panels. It was created back in the mid-1990s for efficient video transmission over low-bandwidth channels; nowadays it is considered obsolete and is found extremely rarely in calling panels, and exclusively as an addition to the more advanced H.264 (see below).

- H.264. A codec widely used in modern video equipment, including for transmitting high-definition video. It provides a good compression ratio while maintaining quality, and is not particularly demanding on computing power, which is why it is extremely popular in our time.

- H.265. The newest and most advanced of the formats found in calling panels. It provides even higher efficiency than H.264, supports resolutions up to 8K, but has quite serious hardware requirements. As a result, support for this standard is...rarely found in calling panels.

Horizontal size of the video panel covered by the camera (see "Type"); this size is most conveniently indicated by the angle between the lines connecting the camera lens with the left and right edges of the scene being viewed.

Theoretically, the wider the viewing angle, the more space the camera is able to cover and the less likely it is that some details will remain out of the frame. At the same time, taking into account the specifics of the use of outdoor panels, it is usually not necessary to equip them with wide-angle cameras; moreover, such optics would be inconvenient due to distortion and reduction effect. Therefore, most models have horizontal viewing angles in the range of 60 – 80 ° — this is quite enough for the intended use.

The vertical size of the video panel covered by the camera (see "Type"), in other words, the angle between two lines connecting the lens with the top and bottom edges of the scene being viewed. The value of the viewing angles is described in detail above in paragraph "Viewing angles horizontally"; we only note that they are usually smaller vertically than horizontally, and in many models this parameter is not indicated at all because of its secondary importance.

This value characterizes the angle of coverage of the image diagonally, this figure is usually slightly larger than the horizontal angle, this is due to the fact that the frame that we see is already in a rectangular form, usually with an aspect ratio of 3 to 4 or 16 to 9, and part of the frame can be circumcised. This indicator, along with the horizontal and vertical viewing angles, allows you to estimate from what distance the visibility of the interlocutor will be acceptable.

The focal length is such a distance from the lens to the matrix, at which a clear image is obtained on the matrix (when the lens is focused to infinity). The viewing angles of the lens primarily depend on this indicator (see above): the smaller it is, the wider the viewing angles and the smaller the objects in the frame (and vice versa). At the same time, it should be noted that the actual viewing angle is determined not only by the focal length, but also by the size of the matrix (see above). In fact, this means that with different sizes of matrices, lenses with the same focal length will have different working angles.