Comparison SJCAM SJDASH vs AutoExpert DVR-817

Glass mount provided in the model with the corresponding type of installation (see above).

Note that in many models, not the recorder itself is attached to the glass, but the bracket, on which, in turn, the device is installed. To learn how to fix the recorder on the bracket, see "Mounting the recorder". And the options for attaching to glass can be as follows:

— Sucker. The traditional suction cup, which works due to the reduced pressure between the mount and the glass — as a result, the force of the pressure of the outside air and holds the structure in place. One of the main advantages of this option is “reusability”: the suction cup can be repeatedly stuck and detached at the request of the user, and after removal it leaves practically no traces. However this type of fastening is considered somewhat less reliable than stickers; however, the suction cups used in video recorders are usually of a special design that provides sufficient reliability for practical use. Therefore, this type of mount is extremely popular in modern registrars.

— Sticker. A plate with a layer of special glue, due to which the entire structure is held on the glass. Such mounts are considered more reliable than suction cups, they are less prone to wear and do not lose effectiveness even with minor damage such as cracks and chips. On the other hand, the sticker is usually installed "once and for all..." and does not provide the ability to quickly remove the bracket. And although dismantling by itself is possible, however, it will not work to reuse the sticker, and the glass will most likely have to be cleaned from traces of glue. So installing a recorder with such a mount requires special care and attention.

Note that some models of DVRs are supplied immediately with both types of mounts described above in the kit. This allows the user to choose the option of their choice — including changing the suction cup to a sticker, if the need arises.

A method of fixing the recorder on a device that plays the role of a mount - a bracket for the windshield, a helmet platform, a clamp for the steering wheel or another similar structure.

— Latch. One of the most popular options nowadays. The latch, along with the magnet (see below), refers to quick-release fasteners, allowing you to easily and quickly remove the device and return it to its place. This feature can be useful, for example, if the car is left overnight in an unguarded place, where an unremoved recorder can become a bait for thieves; In addition, the entire device sometimes has to be removed to view and copy footage. Specifically, latches are considered more reliable than magnets; they can be used even with the most massive devices, and are also cheaper to produce.

- Magnet. Another type of quick-release mount: a powerful permanent magnet that is strong enough to hold the recorder in place. This type of fastener is easier to use than a latch: to install it, just “stick” the device to the mount, and to remove it, just pull it hard. Another advantage is that the latch can be broken by unsuccessfully applying force, whereas in magnets there is practically nothing to break. On the other hand, this type of mount is less reliable: in the event of a shock or a powerful jerk, the force of attraction may not be enough. Therefore, although magnets ar...e widespread, they are still inferior in popularity to latches.

— Magnet/latch. An option that involves the presence of both types of mount in the kit - both a magnet and a latch. This allows you to choose an option at your discretion depending on the situation. For example, for quiet movement around the city and frequent stops during which you have to remove the recorder, a magnet is better suited, and a more reliable latch will be useful on a long journey, especially if the roads are of poor quality. At the same time, such versatility is not required so often, which is why this option has not become widespread.

- Screw. Fixation with a screw that is screwed into a socket on the recorder body. Connecting and disconnecting such a fastener takes noticeably longer than in the case of a latch or magnet, however, the reliability of fasteners of this type is very high - even a strong tug is more likely to tear off the suction cup or sticker that holds the entire structure than damage the screw mount.

— Fixed / non-removable. An option found exclusively in windshield recorders installed using a sticker (see “Attaching to glass”). The platform with the sticker in such models is rigidly fixed to the body; and in some models the role of such a platform is played by the upper side of the body, specially made flat. The advantages of fixed mounts are simplicity, compactness and high reliability. On the other hand, this installation method requires the recorder to be permanently on the glass and does not allow you to quickly remove it and put it back: removing the sticker is quite difficult, and it cannot be reused.

The sensor is a key element of any digital camera; it is from it and from signal processing technologies that the quality of the resulting image primarily depends. In this case, the type refers rather to the brand or brand of the matrix; it is usually indicated if the recorder is equipped with a high-quality sensor that is noticeably superior to most solutions on the market.

One of the most popular such options is Sony. The specific characteristics of the matrices ( IMX179, IMX222, IMX291, IMX307, IMX317, IMX322, IMX323, IMX326, IMX335, IMX415) may vary, but anyway, such a sensor is a sign of a high-end DVR.

In addition, there are models equipped with matrices from other manufacturers — Aptina, OmniVision, Samsung(GalaxyCore), Sandvik. Such solutions are generally considered to be simpler and more democratic than Sony — both in terms of price and functionality. Nevertheless, Samsung has a lot of developments in the field of electronics, and even such r...elatively “simple” sensors are usually more advanced and of higher quality than “know-names”.

Another manufacturer that produces fairly high-quality matrices is Panasonic. Such sensors are not as widespread as those described above, but they are still found in video recorders, including pretty advanced.

Model of the processor used in the dashcam

The term "video chip" is used mainly for devices with classic capabilities, "processor" — for advanced models with an abundance of non-standard functions. However, anyway, we are talking about the same component — the main computing unit, the characteristics of which directly affect the capabilities of the recorder as a whole. Knowing the model of the processor, you can find detailed data on it and evaluate how satisfied you are with a device based on such electronics. Of the most advanced modern chips, one can name, in particular, Ambarella A7L, Ambarella A12, Novatek NTK96655, Novatek NTK96660 and HiSilicon Hi3516.

The maximum resolution and frame rate of video taken by the recorder in the Full HD (1080p) standard.

Many people associate the term Full HD with a resolution of 1920x1080 — and indeed, this resolution is very popular, including among DVRs. However, this standard also covers other options — in particular, 1440x1080 (4:3 aspect ratio) and 1920x540 (halved vertical size). In general, support for this resolution is a good indicator for a modern registrar, indicating that the device belongs to at least an average level.

As for the frame rate, the higher it is, the smoother and less blurry the video will be, the better the details on moving objects will be visible, and also the more space the footage will take up. It is worth noting here that in low-cost Full HD recorders, shooting can be carried out at very low speeds — 15 fps or even 10 fps. Such a shooting speed allows you to watch video more or less normally, but for a normal display of moving objects, a higher frame rate is still desirable — at least 25 frames / sec.

The maximum resolution and frame rate of video taken by the recorder in the Super HD standard.

Super HD is a rather specific standard that exceeds Full HD in resolution, but falls short of Quad HD. The traditional frame size for this format is 2304x1296, but there are models with a lower horizontal resolution — 1728x1296. Anyway, Super HD is quite popular among DVRs: it provides good detail and does not require particularly powerful hardware.

As for the frame rate, the higher it is, the smoother and less blurry the video will be, the better the details on moving objects will be visible, and also the more space the footage will take up. However, in Super HD models this figure usually ranges from 25 to 30 fps, and this difference is hardly fundamental.

Among the photo and video functions used in the dashcam, we can distinguish G-sensor, rotating lens, live, HDR< /a>, WDR, polarizing filter, DEWARP and Time Lapse. More about them:

— G-sensor (video saving). A sensor that monitors shocks and vibrations acting on the DVR. The main function of this sensor is to ensure the safety of video materials in the event of an accident: in the event of a strong impact, characteristic of a collision or fall, the recorder with a G-sensor automatically saves the previously recorded video to a non-volatile memory protected from overwriting. Thus, materials about an emergency are not only guaranteed to be saved, but with a high probability remain intact even if the recorder itself is damaged. In addition, the G-sensor is used in parking mode — see "Functions" for details.

— Swivel lens. The ability to rotate the lens of the registrar horizontally or vertically, and in some cases — on both planes. This feature allows you to adjust the camera's field of view.

— Sound recording. Ability to record sound with a video recorder. First of all, we are talking about recording conversations in the cabin, which can become an add...itional argument in disputable situations — for example, they will allow you to determine whether the driver was talking on a mobile phone at the time of an accident, whether he noticed the situation on the road, how he assessed it, etc.

— Live broadcast. Allows you to remotely connect to the DVR and monitor what is happening from the camera in real time. It is very important if there is an additional camera in the cabin, when you can track the situation, for example, in taxi services, courier delivery, etc. This function will also become important and useful when a car is stolen, when you can not only see the hijacker from the video from the camera, but also track the route of his movement.

— HDR (high dynamic range). A function that increases the dynamic range of the recorder. Dynamic range is the maximum difference between the brightest and darkest area achievable within a single frame. Initially, this range for digital matrices is small, so an image with large brightness differences (for example, a road against a sunset sky) turns out to be either strongly overexposed in bright areas or very dim in dark areas. HDR addresses this shortcoming and also improves the overall colour quality. This is implemented as follows: the camera takes several frames with different settings and from them forms the finished image. At the same time, this technology is simpler and cheaper to implement than WDR, which is similar in purpose (see below). The main disadvantage of HDR is that this type of shooting increases the blurring of fast moving objects in the frame somewhat.

— WDR (Wide Dynamic Range). A function similar in purpose to HDR described above: it is used to improve the quality of a “picture” that has strong differences in brightness. The key difference between these technologies is that WDR works at the hardware level — due to high-end matrices. This allows you to achieve the required dynamic range within a single frame and do without gluing several frames — as a result, WDR, unlike HDR, does not give a blurring effect and does not worsen the detail of moving objects in the frame. The downside of this quality is the high price.

— Polarizing filter. The presence of a polarizing filter in the main camera of the DVR. Such a filter reduces the brightness of glare arising from strong light on glass, water and other similar surfaces. This greatly improves image quality, especially when shooting in sunny weather.

— DEWARP. A technology used to correct the "picture" obtained using a wide-angle lens. Such lenses are often used in DVRs; one of their drawbacks is their propensity for the fish-eye effect, the characteristic distortion when straight lines in the frame turn into rounded ones. The DEWARP function eliminates this shortcoming — it "bends back" curved lines, correcting the geometry of objects in the frame. Note that such a correction does not always work 100% accurately, however, the picture processed by DEWARP is anyway more reliable than without this technology.

— Time Lapse. A special mode of operation in which video recording is carried out at a slow frequency, which in practice is mainly used for shooting slow processes. Thus, for example, a long journey or a long sunset can fit into a 3-minute video.

— Radar detector. A sensor that reacts to the radiation of a police radar and warns the driver that the speed of movement can be recorded by the device. DVRs with this function are classified into a separate category - combo devices (see “Type”). Let us remind you that radar detectors are also available as separate devices, but the combo device takes up less space when installed. On the other hand, the “anti-radar” functionality in combined video recorders is generally somewhat more modest than in separately made radar detectors. And combo devices are quite expensive (although, most often, they are cheaper than a pair of a separate recorder and a radar detector with similar capabilities). We would like to emphasize that the presence of this function does not relieve you of the obligation to adhere to the speed prescribed by the traffic rules.

— Signature recognition. A function of the radar detector described above that improves recognition accuracy and reduces the likelihood of false alarms. To do this, samples (signatures) of emissions from the most popular radar models are entered into the device’s memory, and when a signal is detected, the device compares it with the data in memory. In this way, you can quite accurately determine whether the received signal is the radiation of a radar (and which one), or whether it is just extraneous interference. The disadvantages of detectors with signature r...ecognition are quite high cost, slightly increased response time and the inability to “recognize” radars that are not stored in memory (however, some models allow updating the signature database).

— Parking mode. A special mode that allows you to record emergency incidents on video while the car is parked; The G-sensor is used for operation (see “Shooting functions”). In parking mode, the recorder is in “sleep” mode, and if the G-sensor detects an impact, full recording starts. In this case, the video from the buffer is “glued” to the beginning of the recording, which allows you to record not only the moment of the incident itself, but also a few seconds before it.

— Motion sensor. Recorder function based on motion detection in the camera lens. Thus, if the recorder “understands” that there is movement in the frame, automatic shooting is carried out. This allows you to configure the DVR to automatically turn on when you start driving, as well as record possible accidents, thefts, and car thefts from parking lots that come into the field of view of your device.

— Voice control. Ability to control the DVR using voice commands. The specific list of such commands (and supported languages) may vary depending on the model. However, in any case, this function contributes to traffic safety: it allows you to keep your hands off the steering wheel and not be distracted from the road when operating the recorder.

— Gesture control. Ability to control the device using gestures. Note that the capabilities of such control in DVRs are very limited: as a rule, a sensor is used for this, which responds to the movement of the user’s hand in front of the device and is capable of performing only one specific action. However, even this feature provides additional convenience and safety (compared to pressing buttons and especially working with menus): moving your hand takes a split second, while the driver is practically not distracted from the road. As for specific functions implemented through gesture control, they may include protecting the recorded video from being overwritten, saving a photo, turning off the sound signal from the radar detector (see above), etc. In some models, such a function is hard-coded in the settings and cannot be reconfigured; in others it is possible to choose one of several options.

— Wi-Fi module. Wi-Fi technology is mainly known as a way to access the Internet wirelessly, but it can also be used to communicate directly with another device. The methods of using this technology in recorders may be different, depending on the functionality. For example, some models are capable of updating map marks for a GPS navigator and a GPS informer database via such a communication (see above); others allow you to upload the captured video directly to the Internet (for example, YouTube); and the most advanced devices with this function have touch screens and, when removed from the mount, can even be used as full-fledged tablets, with the ability to view web pages and install various applications. There are also quite specific possibilities - for example, broadcasting filmed or filmed video to a smartphone or tablet, distributing mobile Internet to other devices (if there is a 3G/4G module), etc. Note that the number of public Wi-Fi access points is constantly increasing, they are available at most large gas stations and are often provided in certain areas of large cities (parks, historical and business districts, etc.). So, accessing the World Wide Web from the recorder without removing it from the car may turn out to be much easier than it looks at first glance.

— 3G/4G modem. 3G or 4G mobile communication module. Designed mainly for data transfer - in other words, for using the mobile Internet; Voice calls for DVRs are considered overkill and are generally not supported. The communication speed in modern mobile networks is often comparable to a communication via Wi-Fi; so the options for using 3G/4G connectivity can be quite varied, depending on the specific model. However, three functions are most often encountered: downloading information about traffic jams and other relevant data (updates for the GPS informer, weather forecast, etc.); work as a GPS tracker (if this function is available - see above); as well as Wi-Fi access point mode, with mobile Internet distribution to other devices (if you have your own Wi-Fi module, of course). If we compare 3G/4G and Wi-Fi, then mobile communications are available almost everywhere, but you have to pay for using it.

— Bluetooth. The recorder has a built-in Bluetooth module. This technology is used for direct wireless communication with other devices; its application may vary depending on the functionality of a particular registrar. One of the most popular options is to broadcast sound to a Bluetooth-enabled radio or to the driver’s headset: these can be various notifications from a navigator, radar detector, etc., signals from the Antison system (see above), and in some models - even music from the built-in player. Another popular application format is exchanging files with a smartphone, laptop or other similar device (primarily copying footage). In addition, other, more specific ways of using Bluetooth may be envisaged. And here it is worth noting that most recorders with this function work on Android (see the corresponding paragraph), so the range of options in them is very extensive - in fact, it is limited to the range of compatible applications.

- Speaker. Own speaker installed in the DVR body. Through such a speaker, for example, audio can be played when watching a captured video, voice prompts from a GPS navigator/informant, signals from a radar detector (see above), etc. However, it is worth considering that the sound power can be quite low, and in a noisy environment it may be difficult to listen to the speaker.

The diagonal of the display installed in the DVR.

A large display, on the one hand, provides additional convenience, on the other hand, it affects the dimensions and price of the entire device. Therefore, manufacturers choose a diagonal in such a way that the device can be used normally and at the same time it is not too expensive and bulky. So, for a classic registrar that does not have additional functions, a small display is enough — 2 – 2.5", 1.5 – 2", or even less : it completely allows you to manage the settings and control what exactly gets into the frame, and to fully view the footage, you still need a computer, TV or other large screen. A size of 2.5 – 3 " by the standards of such devices can already be called average, and screens of 3" or more are typical mainly for fairly advanced models, often with an abundance of additional functions.

Also note that there are models that do not have a display at all. To control the operation parameters and check the position of the frame, such a recorder is connected to an external device — for example, to a smartphone via Wi-Fi.