Comparison RS DVR-405F vs ParkCity DVR HD 900

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 recorded by the recorder in the HD (720p) standard.

The classic resolution for this standard is 1280x720, but there are other options in DVRs — in particular, 1280x960 (4:3 aspect ratio). Anyway, HD is not outstanding, but quite a decent indicator that allows you to get a video with good detail (for example, it is usually quite possible to make out numbers on cars in close proximity to a car on it).

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 some inexpensive models, shooting in HD at very low speeds — 15 – 20 fps is used to reduce the cost. 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. It is also worth saying that, in general, for a comfortable perception by a person, a speed of 24 to 60 frames per second is considered quite sufficient, however, among the registrars there are models that can shoot HD at 120 fps. The meaning of this speed is to ensure that individual details on moving objects are as clearly visible as possible in slow motion or frame-by-frame viewing.

The viewing angle provided by the main camera of the DVR. As a rule, it is indicated along the diagonal of the frame, less often - horizontally, because of this, models with the same numbers in the characteristics may differ somewhat in the actual field of view. So if you have doubts about this, when choosing, it does not hurt to find and watch video samples from different models.

Other things being equal, a wider viewing angle allows you to cover more space, but individual details in the frame are smaller. In addition, wide-angle lenses give geometric distortions of the image (however, DEWARP can be provided to eliminate them, see "Functions"). As for specific figures, viewing angles up to 120° inclusive are considered relatively small for modern registrars, values of 121 - 140 ° can be called average, 141 - 160 ° are above average, and the most wide-angle models are able to cover a space of more than 160 °.

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.

— Speed on video. The ability to display data on the current speed of the car on the video being shot - usually in the form of numbers in one of the corners of the frame. As a rule, the device receives speed information from the built-in GPS sensor (see below). This function can be especially useful when analyzing ambiguous situations - for example, as additional evidence that the driver did not violate the speed limit.

— GPS module. Built-in GPS satellite navigation module, which allows you to determine the current coordinates of the device. The specific ways in which this information can be used may vary depending on the other functionality of the registrar. Thus, it is data from GPS that is used to display speed on video (see above), as well as for the operation of the GPS informer and GPS navigator described below. There are other options, sometimes quite original - for example, if you have a 3G/4G modem, a beacon mode may be provided ( GPS tracker - see below).

— GPS informant. A function that provides the driver with various useful information related to the current location. As the name suggests, the location itself is determined using GPS. One of the most popular ways to use an informant is to warn of approaching traffic cameras, stationary post...s and speed control systems that are not detected by a traditional radar detector. In addition, other similar functions may be provided - for example, a message about an area with a high accident rate or a separate large hole on the road. To operate the GPS informer, a database of relevant objects is entered into the device’s memory; When purchasing, it doesn’t hurt to clarify what exactly this database contains, how fresh it is, and whether it allows for updating and manually adding points.

— GPS navigator. The device can operate as a full-fledged GPS navigator. For this, in addition to the GPS module itself, the design provides built-in maps, as well as a fairly large display to display them. This allows you to do without purchasing and using a separate navigator, but this function is not particularly popular in modern DVRs. Firstly, it significantly affects the cost of the device; secondly, a regular smartphone or tablet with GPS is often enough to navigate on public roads; thirdly, recorders most often have rather modest navigation capabilities and are often inferior even to smartphones/tablets, not to mention specialized devices.

— GPS tracker. Another function found in recorders with a GPS module (see above). A GPS tracker allows the device to operate in beacon mode, constantly transmitting data about the location of the car to one or another recipient - for example, taxi service dispatchers, the customer of cargo transportation, etc. Such beacons are also sold as separate devices, but it is easier (and sometimes cheaper) to buy and install a recorder with this function. In any case, it is worth considering that a 3G/4G modem is usually used to transfer data (see below) - so to use the tracker you will have to buy a SIM card and regularly pay for mobile communications.

— GLONASS. The device supports the GLONASS navigation system, the Russian analogue of the GPS described above. Most often, this function is provided in addition to the GPS module: simultaneous use of two systems improves the speed and accuracy of positioning, and also provides an additional guarantee in case of failures in one of them.

—Galileo. European satellite navigation system, created as an alternative to American GPS. Note that it is under the control of civilian departments, not the military. With a full fleet of 24 active satellites, the system provides an accuracy of up to 1 m in public mode and up to 20 cm with the GHA service. Working in conjunction with GPS, Galileo provides more accurate position measurements, especially in densely populated areas.

The maximum video resolution supported by the optional DVR camera. Depending on the design and configuration, we can talk about both a remote camera and a camera for filming the interior (see above for both); this nuance should be clarified separately.

The higher the resolution, the more detailed the image from the camera will be, the more small details will be normally visible on it. On the other hand, high detailing affects the volume of materials to be filmed and the requirements for the “hardware” of the registrar (and, accordingly, affects the cost).

In general, additional cameras of modern recorders can be divided into the following categories:

— SD. "Standard" resolution (as opposed to HD — "high resolution"). A rather modest frame size, which at the same time allows you to significantly save memory for video recording and is suitable even for low-cost recorders. Specific resolution options include, but are not limited to, 628x582, 640x480, and 720x480.

— HD 720p. The traditional, most popular resolution for this video recording standard is 1280x720. In addition to it, registrars also found 960x720 (aspect ratio 4:3) and reduced in height 1280x480. HD is the most modest of today's high-definition standards, but still provides pretty decent detail.

— Full HD 1080p. The "classic of the genre" for this standard is the resolution of 1920x1080, however, there are other values in registrars, including very speci...fic ones — such as 1440x1080 (4:3 aspect ratio) and 1920x540 (halved vertical resolution). This is a fairly solid indicator even for the main camera of the registrar, and there is no need to talk about additional ones.

— Super HD. Not a particularly popular standard in video technology, which, nevertheless, has found application in video recorders. Most often provides a resolution of 2304x1296, which provides even more

Maximum video frame rate supported by the optional DVR camera. Depending on the design and configuration, we can talk about both a remote camera and a camera for filming the interior (see above for both); this nuance should be clarified separately. Anyway, it is with this frequency that the shooting is carried out by default.

The higher the frame rate, the clearer the moving objects will be on the video, the less they will be blurred and the less “jerky” the video itself will be. It is believed that the most comfortable for the human eye is a speed of 24 to 60 frames per second; a lower frequency is already perceived as a “slideshow”, and a higher one only increases the amount of material being shot, without giving a visible increase in quality. At the same time, registrar cameras can also provide higher filming speeds than 60 fps — this provides good visibility of individual moving parts in slow motion or frame-by-frame playback.

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.

Resolution of the display installed in the recorder.

The higher the resolution (with the same diagonal) — the clearer the image is, but the more expensive the screen itself. At the same time, high resolutions are not needed to set the camera in the desired position and to work with the basic settings of the device. So you should pay attention to this parameter only if you plan to use additional functions that require a high-quality “picture” — for example, a GPS navigator (see “Functions”) or a remote camera that plays the role of a reversing camera.