Comparison Canon EOS R8 body vs Sony A7 IV body

The result shown by the camera in the DxOMark ranking.

DxOMark is one of the most popular and respected resources for expert camera testing. According to the test results, the camera receives a certain number of points; The more points, the higher the final score.

The total number of individual light sensitive dots (pixels) provided in the camera's sensor. Denoted in megapixels - millions of pixels.

The total number of MPs, as a rule, is greater than the number of megapixels from which the frame is directly built (for more details, see "Effective number of MPs"). This is due to the presence of service areas on the matrix. In general, this parameter is more of a reference than practically significant: a larger total number of MPs with the same size and effective resolution means a slightly smaller size of each pixel, and, accordingly, an increased likelihood of noise (especially at high ISO values).

The number of pixels (megapixels) of the matrix directly involved in the construction of the image, in fact — the number of points from which the captured image is built. Some manufacturers, in addition to this parameter, also indicate the total number of MPs, taking into account the service areas of the matrix. However, it is the effective number of MPs that is considered the main indicator — it is this that directly affects the maximum resolution of the resulting image (see “Maximum image size”).

A megapixel is 1 million pixels. Numerous megapixels ensures high resolution of the captured photos, but is not a guarantee of high-quality images — much also depends on the size of the sensor, its light sensitivity (see the relevant glossary items), as well as hardware and software image processing tools used in the camera. Note that for small matrices, high resolution can sometimes be more of an evil than a blessing — such sensors are very prone to the appearance of noise in the image.

The maximum size of photos taken by the camera in normal (non-panoramic) mode. In fact, this paragraph indicates the highest resolution of photography — in pixels vertically and horizontally, for example, 3000x4000. This indicator directly depends on the resolution of the matrix: the number of dots in the image cannot exceed the effective number of megapixels (see above). For example, for the same 3000x4000, the matrix must have an effective resolution of at least 3000*4000 = 12 million dots, that is, 12 MP.

Theoretically, the larger the size of the photo, the more detailed the image, the more small details can be conveyed on it. At the same time, the overall image quality (including the visibility of fine details) depends not only on resolution, but also on a number of other technical and software factors; see "Effective MP number" for more details.

The sensitivity range of a digital camera matrix. In digital photography, light sensitivity is expressed in the same ISO units as in film photography; however, unlike film, the light sensitivity of the sensor in a digital camera can be changed, which gives you more options for adjusting shooting parameters. High maximum light sensitivity is important if you have to use a lens with a low aperture (see Aperture), as well as when shooting dimly lit scenes and fast-moving objects; in the latter case, high ISO allows you to use low shutter speeds, which minimizes image blur. However, note that with an increase in the value of the applied ISO, the level of noise in the resulting images also increases.

The presence in the camera of a special mechanism for cleaning the matrix from dust and other contaminants.

This function is found only in models with interchangeable lenses — "reflex cameras" and MILC (see "Camera type"). When replacing the lens in such cameras, the sensor turns out to be open, and the probability of its contamination is quite high; and extraneous particles on the matrix, at best, lead to the appearance of extraneous artifacts, at worst, to damage to the sensor. To avoid this, cleaning systems are provided. They usually work on the principle of ultrasound: high-frequency vibration "resets" debris from the surface of the sensor.

Note that no cleaning system is perfect — in particular, such systems are “too tough” for condensate, salt deposits and other similar contaminants. So the matrix may still need manual cleaning (ideally, in a service centre). Nevertheless, this function allows you to effectively deal with at least dust, which greatly simplifies the life of the user.

The type of bayonet mount — mount for interchangeable lenses — provided in a SLR or MILC camera (see "Camera type"). Bayonets come in different sizes, and interchangeable lens specifications usually indicate which mount it is designed for. Most often, mounts of different types are not compatible with each other, but there are exceptions (sometimes directly, sometimes using adapters).

Also note that one brand can use different mounts for different classes of cameras — and vice versa, one mount can be used by several manufacturers. So, Canon releases cameras with mounts EF-M, EF-S, EF and Canon RF. Leica has Leica M, Leica SL, Leica TL. Nikon has in its arsenal Nikon 1, Nikon F, Nikon Z. Pentax — Pentax 645, Pentax K, Pentax Q. Samsung offers NX and NX-M mounts. Sony cameras have Sony A and Sony E, Fuji has Fujifilm G and Fujifilm X. And as an examp...le of a mount used by different brands, one can cite Micro 4/3, which is widespread in Olympus and Panasonic cameras.

An image stabilization method provided by a camera. Note that optical and sensor-shift systems are sometimes combined under the term "true" stabilization, due to their effectiveness. See below for more details.

Stabilization itself (regardless of the operating principle) allows you to compensate for the "shake" effect when the camera is not positioned correctly - especially when shooting handheld. This is especially important when shooting with significant magnification or at long shutter speeds. However, in any case, this function reduces the risk of ruining the frame, so cameras with stabilization are extremely common. The operating principles can be as follows:

— Electronic. Stabilization is carried out by means of a kind of “reserve” — a section along the edges of the sensor, which is not initially involved in the formation of the final image. However, if the camera electronics detect vibrations, it compensates for them by selecting the necessary fragments of the image from the reserve. Electronic systems are extremely simple, compact, reliable and at the same time inexpensive. However, for their operation, it is necessary to allocate a fairly significant part of the sensor — and reducing the useful area of the sensor increases the noise level and degrades the image quality. And in some models, electronic stabilization is enabled only at lower resolutions and is not available a...t full frame size. Therefore, in its pure form, this option is found mainly in relatively inexpensive cameras with non-replaceable optics.

— Optical. Stabilization is achieved when light passes through the lens — due to a system of moving lenses and gyroscopes. As a result, the image gets to the sensor already stabilized, and the entire area of the sensor can be used for it. Therefore, optical systems, despite their complexity and rather high cost, are considered more preferable for high-quality shooting than electronic ones. Separately, we note that in SLR and MILC cameras (see "Camera type") the presence of this function depends on the installed lens; therefore, for such models, optical stabilization is not indicated in our catalog in principle (even if the kit lens is equipped with a stabilizer).

— With sensor shift. Stabilization performed by shifting the sensor "following" the shifted image. Like the optical one described above, it is considered a fairly advanced option, although in general it is somewhat less effective. On the other hand, sensor shift systems have serious advantages — first of all, such stabilization will work regardless of the characteristics of the lens. For cameras with non-replaceable optics, this means that the lens can do without an optical stabilizer and make the optics simpler, cheaper and more reliable. In SLR and MILC cameras, sensor shift allows even "non-stabilized" lenses to be used with convenience, and when "stabilized" optics are installed, both systems work together, and their efficiency is very high. In addition, sensor shift is somewhat simpler and cheaper than traditional optical stabilizers.

— Optical and electronic. Stabilization that combines both of the above options: initially, it operates on an optical principle, and when the lens's capabilities are not enough, an electronic system is connected. This allows for an increase in overall efficiency in comparison with purely optical or purely electronic stabilizers. On the other hand, the disadvantages of both options in such systems are also combined: the optics are comparatively complex and expensive, and not the entire sensor is used. Therefore, such a combination is rare, mainly in individual advanced digital compacts.

— With sensor shift and electronic. Another type of combined stabilization systems. Like "optical + electronic", it improves the overall efficiency of stabilization, but at the same time combines the disadvantages of both methods (they are also similar: more complicated and more expensive camera plus a decrease in the useful area of the sensor). Therefore, this option is used extremely rarely - in single models of digital ultrazooms and advanced compacts.

The presence of two control dials in the design of the camera.

This design feature makes it easier to control the camera and change settings on the fly: additional operating parameters are transferred to the second disk, and turning it to the desired position is easier and faster than “digging” in the on-screen menu items. This feature is found mainly in semi-professional and professional cameras, which involve frequent use of manual shooting mode.