Comparison SJCAM SJ7 Star vs Sony HDR-AS30V

— Oblong. Oblong action cameras — they look like an elongated rectangle (parallelepiped) or a cylinder, while the lens is placed on one of the narrow ends. This is the difference between the oblong cameras and the conventional ones described below. This layout is convenient primarily because it allows you to hold the camera in your hand securely. On the other hand, the control panel and display during shooting are often turned away from the user, which can create some inconvenience. However, this can be offset by the use of folding displays and other similar features; and in some situations, the side display and controls even prove to be an advantage.

— Vertical. Oblong action cameras that are stretched up and have a lens at the top. Such models are very similar to chest cameras and can be used for such purposes. However, their main use is shooting yourself and holding it in your hand. It is for this purpose that the case is made elongated, which makes it convenient to cover it with your hand.

— Conventional. The camera body has the shape of a rectangle, but the lens is placed on its wide, frontal edge. Outwardly, such models are most similar to classic digital cameras. Some may have a fairly large display, placed on the opposite side of the lens, as in the same photo cameras, which allows the user to see the shooting scene in real time. However, the l...ocation of the lens, usually, does not affect the technical specs of the camera itself, and therefore both conventional and oblong models can provide the same video quality.

— Cube. A fairly specific type of action camera, the body of which has the shape of a compact cube. Usually, such models are relatively small in size, but the size reduction, in turn, affects the video capabilities and overall functionality. For example, such models are extremely rarely equipped with displays (although many of them can be connected via Wi-Fi to a smartphone or tablet, which compensates for this disadvantage).

— Glasses with a camera. Devices in the form of sports glasses with a built-in camera. The lens of such a camera is usually located between the glasses lenses, less often on the side, based on one of the temples; during normal use, it constantly “looks” approximately in the same direction as the user himself. Also, the advantages of cameras of this type include accuracy and stealth. On the other hand, in glasses, the additional electronic filling must be very tiny, which makes it difficult to use advanced optics and severely limits the battery capacity. And even with this in mind, such devices are heavier and bulkier than ordinary sports glasses. Another disadvantage is that the camera and frame with lenses cannot be matched separately — as a result, a model with a suitable camera may not be suitable due to the size or style of the glasses, and vice versa.

— Camera mask. A protective mask with a built-in camera. Note that such masks can have different specializations — for scuba diving, motocross, skiing, etc.; these details must be clarified before purchase. However, the lens in such devices is usually located in the middle of the forehead, so the camera takes POV photos and video. The main disadvantage of such devices is that when choosing, you need to take into account both the technical specs of the camera and the purpose and convenience of wearing the mask. In other words, a good camera can be built into an inappropriate mask, and vice versa.

— Camera with a clip. Action cameras fall into this category, for which a clip-on mount is standard. Many of them can be additionally equipped with other mounts, but primarily designed for this type of use and may not be the best purchase for extreme video shooting. On the other hand, such a mount is quite versatile, since it allows you to attach the camera to almost any piece of equipment (backpack strap, unloading belt, belt, etc.).

— Sphere. The shape of the body is found mainly in panoramic and 360° cameras (see "Product type") — it is in such devices that the spherical body is often the most convenient. In the case of conventional action cameras, "sphere" usually means a cylindrical body with a lens on a flat end; such cameras are similar to conventional cameras (see above) and do not have fundamental differences from them.

The ability of the camera to record HD video (720p).

The official HD specification provides a resolution of 1280x720. However, in action cameras, there may be resolutions slightly different from this parameter, for example, 1080x720 or 1440x960. Anyway, HD is the most modest of today's high-definition standards, which, nevertheless, provides a fairly clear and detailed image.

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 for video, 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 higher frame rates at HD resolutions — 100 fps, 120 fps, 200 fps and even 240 fps. This speed is usually used for recording slow-motion video, but such a possibility needs to be specified separately.

The ability of the camera to shoot QuadHD video.

This standard includes an extensive set of resolutions — from 1440 to 3456 pixels horizontally and from 1440 to 2160 pixels vertically, with almost two dozen intermediate options. It is a rather specific transitional option between the relatively inexpensive FullHD 1080p and the demanding UltraHD 4K, allowing you to shoot higher resolution video than 1080p without significantly increasing the cost of equipment. Note that pure QuadHD resolutions are rare in TVs and monitors, but modern technologies make it possible to comfortably watch videos of this format on any high-resolution screen.

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. For example, a filming speed of 25 fps or 30 fps approximates the standard frame rate in film and television; such an image is quite viewable, but fast-moving objects in the frame will look blurry. With an increase in speed to 60 fps, this effect becomes almost imperceptible. The highest QuadHD frame rate found in modern action cameras is 120 fps; this frequency is used when shooting slow-motion video (as well as models with a frequency of 100 fps) because at a n...ormal playback speed, 60 fps is enough.

The ability of the camera to shoot Ultra HD 4K video.

This format covers several resolutions in which the horizontal frame size is approximately 4K pixels. The most popular in action cameras is 3840x2160 (twice the FullHD frame on each side), but there are other options — for example, 3840x1920, corresponding to an aspect ratio of 2:1. In general, 4K is a kind of successor to Full HD: among HD standards that surpass Full HD, UltraHD is the most popular, in particular, many advanced TVs are produced with 3840x2160 screens. On the other hand, this format is quite demanding in terms of processing power and memory, so it is relatively rare in action cameras, mainly among premium models.

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. However, in UltraHD mode, most modern action cameras produce a very low frame rate — most often 30 fps, and in some models 24 fps or even 15 fps. This video is quite viewable, but fast movement in the frame may look blurry. There are cameras capable of shooting UltraHD at a solid speed of 60 fps — the blurring effect during such shooting is almost imperceptible. However, such a model cost is high.

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.

For models with several lenses, as a rule, this parameter is indicated for each lens.

Most often (unless otherwise indicated), the specifications indicate the field of view by the diagonal of the frame; in some ultra-wide-angle lenses it can exceed 180°. A special case is made up of lenses for which a 360° view is declared: this means that the optics cover the entire hemisphere in front of it. Such lenses are found in panoramic and 360-degree cameras (see “Product type”).

In general, the field of view primarily determines what area of the scene is being captured into the frame. Accordingly, the wider it is, the more space the camera captures, and the lower the likelihood that something that is happening will be off-screen. On the other hand, it is worth considering that a strong increase in the field of view leads to distortions of the “picture”, especially at the edges, as well as, to a decrease in the size of visible objects and a decrease in detail. Detailed recommendations regarding choosing a camera based on this parameter can be found in special sources.

The number of built-in microphones provided in the camera.

This parameter is indicated only for models that have more than one microphone. This design provides additional capabilities, but the range of these capabilities depends on the number of microphones and the features of a particular model. So, most often such devices have two microphones; this can be a pair for recording stereo sound, or one microphone can work to record sound, and the second one can act as a sensor for the noise reduction system (see above). A larger number - 3 or 4 microphones - is found mainly in 360-degree cameras (see “Product type”), where such equipment is used to record “surround” multi-channel sound.

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.