Comparison SJCAM SJ4000 vs GoPro HERO3+ Silver Edition

The degree of dust and water protection of the protective case supplied with the camera.

Protected case will save your camera from dust, water, temperature changes, shocks, etc. The specific degree of protection is indicated according to the international IP (Ingress Protection Rating) system, according to which each device is assigned a code of the form IPXX, where X is replaced by specific numbers. The first of them characterizes the protection against the penetration of foreign objects (from 0 to 6, where 0 is no protection). Usually, in boxes for action cameras, this indicator does not go below 5, because otherwise the container would have too large gaps, and its use simply would not make sense. Level 5 provides dust resistance — dust can get inside the case, but in small quantities that do not affect the device inside. Level 6 corresponds to complete imperviousness to dust.

The second digit is protection against liquid ingress (from 0 to 8, where 0 is no protection). Usually, the minimum level of protection against water is 6.

6 — protection against short-term immersion (for example, falling into a sea wave);
7 — protection against temporary immersion under water (up to 30 minutes) to a shallow depth (up to 1 metre), without continuous operation in immersed mode;
8 — protection against immersion to a depth of more than 1 metre for a time of more than 30 m, with the possibility of continuous...operation underwater. The specific level of protection of level 8 can be quite impressive — up to the possibility of diving to several tens of metres.

Note that protective cases for action cameras can be sold separately. Therefore, if the capabilities of the complete container do not suit you, there may be a more secure case on the market. On the other hand, in general, it is still more convenient to buy such an accessory immediately with a camera — so as not to waste time and effort on choosing the right protective case.

The ability of the camera to shoot Full HD (1080p) video.

The standard image size in this standard is 1920x1080. However, in the case of action cameras, this category also includes some other resolutions that are similar in quality, for example, 1440x1080. In general, Full HD provides a very good balance between image quality, the volume of captured files and the processing power requirements for processing them, which makes this standard very popular in modern video equipment — both in cameras and in TV monitors.

Another important parameter given in this paragraph is the frame rate. The higher it is, the smoother the movement in the frame will be, and the details in dynamic scenes will be visible clearly. Technically, 30 fps or even less is enough, but 60 fps is considered the perfect value — at this frame rate, motion blur becomes almost imperceptible and at the same time the size of the captured files remains within reasonable limits. However, there are cameras on the market with a higher frame rate at FullHD resolutions — 90 fps, 100 fps, 120 fps and even 240 fps. This speed is usually used for shooting slow-motion video, but the possibility of such shooting needs to be specified separately.

Frame rate supported by the camera when shooting in slow motion.

In general, such shooting is called “high-speed” because it is carried out at an increased frame rate (more than 60 fps). As a result, when played back at normal speed (60 fps and below), the video looks slow hence the name. This kind of slow-motion can be used just for fun, as an artistic technique, and even for scientific purposes — to capture movement that is too fast for the human eye. In any case, the higher the slow-mo frame rate, the more you can slow down the video and the more advanced the camera is in this regard. On the other hand, the higher the frame rate, the more performant the graphics part should be; and this, in turn, affects the price of the device, sometimes quite noticeably.

We also note that slow-mo shooting may be available only at certain resolutions, not always at maximum. These points can be directly specified in the specs of the action camera.

The number of megapixels in the action camera sensor, in other words, the resolution of this sensor(1 megapixel is 1 million photosensitive points).

There is an opinion that the higher the resolution, the better the image quality. It is true from the point of view that manufacturers are trying to install high-resolution sensors in advanced cameras. At the same time, there are no strict dependencies here, and from the technical point of view, the number of megapixels determines only the maximum image resolution that can be captured using this sensor. The quality of this picture will depend both on several features of the sensor itself (size, type, special design solutions), and the specs of the camera. So when choosing, you should focus not so much on the resolution of the image sensor, but on the general class of the camera and reviews with examples of footage.

The maximum resolution at which the action camera can take photos. Specified in pixels horizontally and vertically.

This parameter is directly related to the resolution of the image sensor(see above): the total number of pixels in the photo, usually, corresponds to the number of pixels in the sensor. For example, a photo resolution of 4608x3456 corresponds to a sensor of 15925248 pixels, or approximately 16 megapixels. If the number of pixels in the photo is greater than the claimed resolution of the sensor, then the manufacturer uses software tricks that allow you to improve the photo resolution to a higher one than originally. This reduces the cost of devices but also affects the quality of images.

Theoretically, high-resolution images can provide good detail, but in fact, much depends on the specs of the sensor (primarily physical size) and image processing features.

— Photo during video. The ability to take photos directly while recording a video — usually using a separate button. Thus, it is convenient to fix the most significant moments of what is happening. Such photos are much better in quality than "freeze frames" from the captured video.

— Serial photo shoot. This feature allows you to take several pictures at once in a short period (usually it is a fraction of a second). A series of shots increases the chance of capturing a good moment, which can be very important given the specifics of using action cameras.

— One click recording. The ability to quickly turn on the camera for recording — literally at the touch of a button, by the name. Moreover, such a button works even if the device is turned off. However, the recording inevitably starts with some delay; but often this delay is a fraction of a second.

— Online streaming. Ability to stream video to popular services like YouTube and social networks (Facebook, Instagram, TikTok, etc.). Usually, the online streaming function is implemented when the action camera is connected to the Internet via a Wi-Fi network, less often via a wired connection. Communication with the World Wide Web can be held directly or through a smartphone or computer. It will require the use of appropriate software.

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

— Auto-rotate. The function of automatic rotation of the captured photos and videos to the position corresponding to the position of the camera. Without this feature, all footage during playback would be displayed strictly in landscape orientation, and footage shot with the camera upside down or upside down would have to be rotated in a photo or video editor. Usually, at the beginning of video recording, auto-rotation is blocked — so that the position of the frame at any time corresponds to the rotation of the camera itself relative to its original position.

— Photo panoramas shooting. The ability to use the camera to take panoramic photos. In traditional action cameras (see "Product type"), such shooting is carried out as follows: the camera takes several separate photos, which are then glued into one image. Regarding panoramic and 360-degree models (see ibid.), it is worth noting that not all such models support shooting in panoramic format, so it is advisable to check the availability of this function separately.

— Key points labels. The ability to add special marks to the footage that indicate key moments. While viewing such videos, you can go directly to the labels — this is easier than manually searching for the right moment. This feature is especially useful when shooting long videos, as well as when numerous individual files. The label, usually, is placed right during the shooting by pressing a special button or by voice command.

— Night shooting. Special mode for recording in low light conditions. The specific implementation of this function may be different: in some models, the sensitivity of the sensor is increased, in others, shooting in the IR range is used. Accordingly, specific features may vary: not every camera with this function can shoot in complete darkness, and these nuances should be clarified separately.

— Diagonal. The larger the screen, the more convenient it is to watch (and also to control if the display is touch-sensitive). On the other hand, the diagonal of the built-in display directly affects the size of the case, and action cameras should be quite compact. Thus, there are practically no screens larger than 2.5" in modern action cameras.

— Resolution. Theoretically, the higher the resolution, the clearer and better image the screen produces. On the other hand, displays in action cameras are designed mainly for menu operation and footage preview — and for these purposes, especially high resolutions are not needed. For models with two screens, the rear display is considered the main display.

— Touch screen. Display equipped with a sensor and responsive to touch like in smartphones/tablets. Control through such a display is simpler and more intuitive than using buttons, rotary knobs, etc. On the other hand, for more or less convenient control, the touch screen must be quite large, which affects the dimensions of the entire camera.

The presence in the camera of a screen mounted on the front panel, next to the lens. Other displays may not be present at all; in such cases, the diagonal, resolution and other parameters are given for the front screen.

It is worth noting that most often the simplest black-and-white displays are installed on the front panel, suitable only for text and basic graphic information. However, even on such a screen, you can display a wide variety of service data: the current mode of operation (photo, video, standby), the resolution used, the shooting time, the amount of free space on the drive, etc. But more advanced displays are not used as front displays: a full-colour screen is needed only for taking a selfie, and for this you can use a remote display with a remote control(see "Control") or a smartphone connected to the camera.

— GPS module. Built-in satellite navigation module that allows you to determine the current coordinates of the device. Options for using data from GPS can be different: geotagging footage, recording travelled routes, determining the speed of movement, or even full-fledged navigation on the map.

— Wi-Fi module. The Wi-Fi wireless module in action cameras can be used in different formats: in some models, it is responsible for connecting to the Internet, in others it is for communicating with a smartphone or other gadget, in others both options are available at once. Anyway, the main use of this connection is to transfer footage to an external device or to the Internet (including broadcasting in the online streaming format, see “Filming capabilities”). In addition, more specific functions can be provided, for example, using a smartphone as an external viewfinder and remote control. Specific features of the use of Wi-Fi in each case should be clarified separately.

— Bluetooth. Direct wireless communication technology for exchanging information between two electronic devices. In action cameras, it is most often used to connect remote controls, selfie sticks and smartphones, which can also act as a remote control. Unlike the Wi-Fi module, it consumes battery power more economically, but at the same time, the range of wireless communication is reduced to 10 m...etres.

— NFC chip. NFC is a wireless communication technology over short distances (up to 10 cm). In action cameras, this technology is mainly used as an auxiliary one, to facilitate connection with a smartphone or other gadget via Wi-Fi or Bluetooth. If such a gadget is also equipped with NFC, just bring the camera to it and confirm the connection — it's easier than fiddling with the settings.

— USB-C. A relatively new type of USB interface that uses a miniature double-sided connector, slightly larger than microUSB. Most often used for similar purposes — as a universal connector through which you can charge the battery and connect the camera to a computer (for copying photos and videos, updating software, etc.). P.). At the same time, USB-C provides a higher data transfer rate than microUSB, supports more power supply, and also has a more convenient plug. Occasionally, there are more specific ways to use this interface — for example, direct connection to a smartphone or tablet that has a USB-C port.

— HDMI output. HDMI is a digital interface specially designed for high-definition video and multi-channel audio. With this output, you can connect the camera to a TV, monitor or other device as an external player and play the footage directly. The convenience of HDMI is that almost all modern video equipment with support for HD standards is equipped with such inputs.

Note that the cameras can be equipped with a smaller version of the connector — miniHDMI or microHDMI; however, finding an adapter cable is usually not a problem, it can even be supplied in the kit.

— Microphone connection. Almost any modern action camera has a built-in microphone that allows you to record sound. However, the quality of its sound is often quite low. Thus, many models can connect an external microphone — you can fix it, for example, on the helmet strap and record the comments of the athlete in the process of movement. Note that different types of connectors can be used for such a connection. As a result, the specific connector type and supported accessories depend on the action camera model, and some devices are only compatible with branded microphones.