Comparison Canon XA11 vs Canon XA25

The physical size of the camcorder sensor. It is usually measured diagonally and is indicated in fractions of an inch — for example, 1/3 "or 1/2.33" (the second option is larger, respectively). In addition, sensors of a “photographic” format can be installed in video cameras, in which case the corresponding designation is used — for example, APS-C.

The larger the sensor, the higher the image quality it can provide (all else being equal). This is due to the fact that on larger sensors, each individual pixel is larger, more light falls on it, which increases sensitivity and reduces noise; this is especially important for shooting in low light. For amateur purposes, small sensors are quite enough, but in professional cameras (see "Features") this parameter is at least 1/3". The exception, however, are models with several sensors (see "Number of sensors") in them each individual sensor is quite small, and high quality is ensured by image processing features.

Focal length of a standard video camera lens in terms of a 35 mm full-frame sensor. This parameter is also called the "equivalent focal length" — EFL.

The focal length itself is the distance from the optical centre of the lens (when focus to infinity) to the sensor, at which the sharpest image is obtained on the sensor. It is one of the key characteristics of any lens, because. determines the viewing angles, the degree of approximation and, accordingly, the specifics of the use of optics. At the same time, it is impossible to compare different options in terms of the actual focal length: the laws of physics are such that with different sizes of sensors, the same focal length will give different viewing angles. Therefore, EFL was adopted as a universal characteristic and criterion for comparison. It can be described as the focal length that a 35mm lens with the same viewing angles would have.

The larger the focal length, the narrower the viewing angle will be and the higher the degree of approximation of the visible scene. Optics with EFL up to 18 mm belongs to the class of ultra wide-angle ("fisheye") and is used primarily to create artistic effects. Distances up to 40 mm correspond to "wide angles", 50 mm gives the same degree of approximation as that of the naked eye, the range of 70-100 mm is considered optimal for portrait shooting, and large values allow the use of optics already as a telephoto lens. Knowing these provisions, one can approximately...evaluate the capabilities of the lens and its suitability for certain tasks; there are more detailed recommendations, they are described in special sources.

Also note that modern video cameras are usually equipped with lenses with a variable focal length (zoom), which allows you to change the degree of approximation and viewing angle; see "Optical Zoom" for details.

Aperture of a standard video camera lens.

This parameter describes how much the lens attenuates the light output. Usually it is written as a ratio between the diameter of the active hole and the focal length of the lens, while the first value is taken as one and denoted as f — for example, f/1.8 or f/5.6. Moreover, the smaller the number in such a record, the higher the aperture ratio: for example, in our example, the first option is “lighter” than the second. Also note that most lenses with a variable focal length (see above) also have a variable aperture — in such cases it is indicated by the range from maximum to minimum (from a smaller number to a larger one).

A high aperture ratio is important primarily when shooting in low light conditions: it allows you to capture an image without “lifting up” the sensor sensitivity and without creating additional artifacts in the form of noise, and in the photo shooting mode, you can also work with shorter shutter speeds (which is useful for dynamic scenes). In addition, the higher the aperture, the lower the depth of field and the easier it is to get a blurry background. Note that for simple everyday tasks this parameter does not play a decisive role, but in professional shooting it can be very significant.

The degree (multiplicity) of zoom provided by the camcorders due to software methods, without changing the focal length of the optics (see "Optical zoom"). The key principle of such an zoom is that part of the image from the sensor is "stretched" to the entire frame. This somewhat worsens the “picture” — after all, not all effective pixels take part in its formation; and the higher the zoom, the worse the quality becomes. On the other hand, this method does not depend on the specifications of the lens and works even with the simplest lenses that do not have zoom lenses, and it is much easier to achieve high magnification than with the optical method.

In modern camcorders, there are two options for using digital zoom. So, among pocket devices (see "Features"), it may be the only available option — not all of them are equipped with zoom lenses. And in full-size models, digital zoom usually complements optical zoom and turns on after the lens reaches the limit of its capabilities.

Note that when shooting 3D (see above), this feature may not be available, and in professional models it is often not used at all.

An image stabilization method provided in the design of a video camera. The stabilization function itself is designed to compensate for small camera shakes so that they are not noticeable in the image. This is especially true when shooting handheld, and in fact most modern models are designed specifically for such usage. According to the method of work, there are such options:

— Optical. A special mechanism with a system of gyroscopes and movable lenses, installed directly in the lens, is responsible for the operation of such stabilization systems. It introduces a correction for all tremors, vibrations, etc., and the “picture” falls on the already stabilized sensor. Optical systems are considered the most advanced and efficient, because. their work allows you to use the entire area of the sensor, fully exploit its capabilities and provide good image quality. Among the shortcomings, it is worth noting the increase in the cost and weight of the cameras, as well as a slight decrease in the reliability of the optics. At the same time, these moments are most often not critical, and stabilizers of this type can be used even in simple and inexpensive models.

— Electronic. Electronic stabilization is carried out due to the fact that not the entire area of the sensor, but only some of it, is involved in the formation of an image for a frame. Simply put, the camera electronics "takes into account" a certain area of the sensor and...transfers the image from it into the frame; and at small displacements, this "area of attention" is also displaced, due to which the visible image remains motionless. The advantages of electronic systems are simplicity of design, lightness, compactness and high reliability; they can be used with even the simplest lenses installed in pocket cameras (see “Features”). Their main disadvantage is the need to reserve a part of the sensor, which reduces the size and resolution of the actually involved area and adversely affects the image quality.

— Optical / electronic. In such systems, both the methods described above are used — both the mechanism in the lens and the reserve on the sensor. This provides extremely high vibration compensation efficiency — the image remains stable even in such conditions in which any single method would be useless. On the other hand, the disadvantages of both options also remain relevant, and the cost of cameras with this feature is quite high.

Video file formats that the camera can use to store recorded footage. If you want to view these materials using a separate device (player, media centre, etc.), you should make sure that this player supports the appropriate formats, otherwise conversion may be necessary.

The range of shutter speeds in which the camera is capable of operating during the shooting process.

Initially, shutter speed is the time during which light affects the photosensitive material (film) when shooting a single frame. For digital sensors, this is the period of time during which an image is read from the sensor to build a separate frame. When shooting video, this interval cannot be more than 1/n, where n is the frame rate (see above), but it can be less — for example, shooting at a frame rate of 30 fps and shutter speed of each frame 1/60 s. There are no such restrictions for the photo mode.

Long exposures are good because they allow the sensor to take in more light — accordingly, the “picture” is brighter, which is especially important in low light. At the same time, they increase the likelihood of getting a blurry image — due to the rapid movement of objects in the frame, the operator's hand shaking and other random camera movements that even the stabilization system is unable to compensate for. This effect can be useful for artistic motion blur, especially when shooting video, but in photo mode it is most often undesirable. Fast shutter speeds, on the other hand, allow you to get clear shots, but with less light, and in the case of video, even with the effect of sharp, jerky movements.

Accordingly, different exposure time options will be optimal for each situation, and the wider their range, the more opportunities the came...ra has to adjust to specific conditions.

Diagonal size of the camcorder's own display in inches. The larger the display, the larger the image on it will be, the easier it will be to work with the screen both during the shooting process and when viewing the footage. On the other hand, a large screen has an effect on the size of the camera itself, you don’t need large sizes to work with a frame, and it’s more convenient to view the footage on a full-sized device like a TV. With this in mind, most modern models are equipped with displays with a diagonal of about 2 – 3.5"; larger screens are extremely rare — even in professional cameras (see "Features"), for which compactness is not a priority.

— Viewfinder. The presence of a viewfinder in the design of the camera — a special optical device in the form of a tube with an eyepiece and a small screen under it. Actually, the role of this device is similar to a conventional display: pointing the frame, controlling the shooting parameters, viewing the footage. The main difference is that in this case the screen is maximally covered and its visibility is almost independent of the ambient light conditions; this is very important in bright sunlight and in other similar situations where outdoor displays "become blind". In addition, the viewfinder can also be useful when stealth is important — it does not reflect on the operator's face and does not unmask it; and such systems consume less energy. On the other hand, the eyepiece during operation must be brought close to the eye; and if the external display allows you to hold the camera, for example, at arm's length above your head, then the viewfinder does not provide such freedom for manoeuvre. Also shooting through such a device can be quite tedious, especially for unaccustomed users; and viewfinders are poorly compatible with glasses. As a result, this element is found mainly in professional models of cameras (see "Features").

— Built-in flash. The presence of a flash in the camera — a light source for taking photos. The most popular use of a flash is to provide illumination in low light conditions;...in addition, it can be used for shooting opposite to a bright light and some other special tasks. In cameras equipped with a backlight (see below), the same lamp can also act as a flash.

— Backlight lamp. The presence of its own lamp to illuminate insufficiently lit scenes in the design of the camera. This lamp differs from the flash described above as it is designed to work during video shooting and operates in constant light mode, and not in impulses. Backlight allows you to use the camera autonomously, without external lighting devices, which can not always be installed. However, do not forget that its operation also consumes battery power.

— Hot shoe. Hot shoe is a specialized mount for installing additional accessories. Most often it is used for external flashes, but not only: external viewfinders, microphones, GPS modules and much more can be attached to the hot shoe. There are several generally accepted standards for this mount, in addition, each manufacturer uses its own set of additional contacts to control advanced features of external equipment; this must be taken into account when selecting such equipment. However, if you intend to use external accessories, it makes sense to choose a camera with a hot shoe. Most of these models are professional (see "Features"), but there are exceptions.

— Built-in speaker. The presence of its own speaker in the camera design. This feature allows you to view footage with sound without the need for additional equipment such as headphones. Note that the quality of the built-in speakers is usually low, and they are not designed for more serious tasks (for example, playing music); and when viewing, they allow not so much to evaluate the quality of the audio, but to determine whether the sound was recorded.

— Built-in projector. The presence of its own projector in the camera design. This feature greatly simplifies the viewing of footage: it allows to provide a fairly large "picture" (with a diagonal of several tens of centimeters) using the camera itself, without the use of TVs or other external screens. However for viewing you will need a suitable surface — at least a plain light wall; but the power of the projectors themselves is low, and in bright light the image may not be visible at all. However, if the video needs to be shown to several viewers at once, this option is definitely more convenient than viewing it on the camera's own screen. In addition, you can watch any video uploaded to memory of a suitable format on the projector — in other words, use the camera as a player.

— Wi-Fi module. The camera has its own Wi-Fi wireless module. This standard is used to build computer networks, and more recently – also for direct communication between various devices: laptops, smartphones, tablets, etc. Specific options for using Wi-Fi may vary depending on the camera model, and include options such as direct copying of content to an external device or even to the Internet (such as YouTube), remote control of the camera, use as a webcam (see below). below), firmware update, etc. And all this is carried out without the use of wires, the communication range can reach 100 m, and the walls are not an obstacle (although they reduce the "range").

— NFC. The presence of a chip for NFC standard wireless communication in the camera. The range of such communication is up to 10 cm, and in cameras it plays an auxiliary role, facilitating the wireless connection of the camera and an external device (smartphone, tablet, etc.) that also has an NFC. Instead of digging through the settings, just bring both devices close to each other and confirm the Wi-Fi connection (see above). Accordingly, this chip is installed only in cameras that have more wireless capabilities.

— GPS module. The camera has a built-in GPS satellite navigation module. By itself, such a module during operation only captures the current location based on data from satellites, but how this data is used depends on the specific camera model. Most often, devices with GPS are able to at least add geotags to the footage — information about the geographical coordinates of the shooting location; but besides this, more extensive features can be provided — for example, search among the materials at the location of the shooting or even full-fledged navigation on the map.

— Detachable microphone. The presence of a mount in the design of the camera for installing an external removable microphone; the microphone itself can be included in the package or purchased separately. This function is typical for professional models and 3D cameras similar in functionality (see "Features") — it allows you to record sound of higher quality and with less noise than when using the built-in microphone.

— Webcam feature. The ability to connect the device to a computer and use it as a webcam — for video calls, broadcasting video directly to the Web, direct recording to a computer, etc. The advantage of camcorders over traditional webcams is the higher resolution and image quality. At the same time, this advantage has not been very noticeable lately, but larger size make camcorders less convenient; Therefore, this function is not widely used.

— Direct copy to HDD. The ability to connect an external hard drive directly to the camera and copy footage to it without using a computer. This feature is especially useful in situations where you need to make a copy (for example, to free up camera memory) and the computer is not nearby.

— Direct printing. The ability to connect the camera to a printer (to print captured photos) directly without using a computer. Software tools in such models can have quite extensive print management options: image selection, printing multiple copies, size and number of prints per sheet, print quality, error messages, etc. Typically, direct printing uses PictBridge technology using a USB connection. It must be supported not only by the camera, but also by the printer; at the same time, the connection does not require additional configuration, driver installation, etc.