Sensor
— CCD (CCD). Abbreviation for Charge-Coupled Device. In such sensors, information is read from the photosensitive element according to the “line at a time” principle — an electronic signal is output to the image processor in the form of separate lines (there is also a “frame at a time” variant). In general, such matrices have good characteristics, but they are more expensive than CMOS. In addition, they are poorly suited for some specific conditions — for example, shooting with point light sources in the frame — which is why you have to use various additional technologies in the camera, which also affect the cost.
— CMOS (CMOS). The main advantages of CMOS matrices are ease of manufacture, low cost and power consumption, more compact dimensions than those of CCDs, and the ability to transfer a number of functions (focus, exposure metering, etc.) directly to the sensor, thus reducing the dimensions of the camera. In addition, the camera processor can read the entire image from such a matrix at once (rather than line by line, as in CCD); this avoids distortion when shooting fast-moving objects. The main disadvantage of CMOS is the increased possibility of noise, especially at high ISO values.
— CMOS (CMOS) BSI. BSI is an abbreviation for the English phrase "Backside Illumination". This is the name of "inverted" CMOS sensors, the light on which does not penetrate from the side of the photodiodes, but from the back of the matrix (from the side of the subst
...rate). With this implementation, the photodiodes receive more light, since it is not blocked by other elements of the image sensor. As a result, back-illuminated sensors boast high light sensitivity, which allows you to create images of better quality with less noise when shooting in low light conditions. BSI CMOS sensors require less light to properly expose a photo. In production, back-illuminated sensors are more expensive than traditional CMOS sensors.
— LiveMOS. A variety of matrices made using the technology of metal oxide semiconductors (MOS, MOS — Metal-Oxide Semiconductor). Compared to CMOS sensors, it has a simplified design, which provides less tendency to overheat and, as a result, a lower noise level. It is well suited for the "live" viewing mode (viewing in real time) of the image from the matrix on the screen or in the camera's viewfinder, which is why it received the word "Live" in the title. They also feature high data transfer rates.Total MP
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).
Light sensitivity (ISO)
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.
Focal length
Focal length of the camera lens.
Focal length is such a distance between the camera matrix and the optical center of the lens, focused at infinity, at which a clear and sharp image is obtained on the matrix. For models with interchangeable lenses (
mirrorless cameras and MILC, see “Camera Type”), this parameter is indicated if the camera is supplied with a lens (“kit”); Let us recall that, if desired, optics with other characteristics can be installed on such a camera.
The longer the focal length, the smaller the viewing angle of the lens, the higher the degree of approximation and the larger the objects visible in the frame. Therefore, this parameter is one of the key for any lens and largely determines its application (specific examples are given below).
Most often in modern digital cameras, lenses with a variable focal length are used: such lenses are able to zoom in and out of the image (for more details, see "Optical Zoom"). For "DSLRs" and MILC, specialized optics with a constant focal length (fixed lenses) are produced. But in digital compacts, "fixes" are used extremely rarely, usually such a lens is a sign of a high-end model with specific characteristics.
It should be borne in mind that the actual focal length of the lens is usually given in the characteristics of the camera. And the viewing angles and the general purpose of the optics are determined not only by this parameter, but also
...by the size of the matrix with which the optics are used. The dependence looks like this: at the same viewing angles, a lens for a larger matrix will have a longer focal length than a lens for a small sensor. Accordingly, only cameras with the same sensor size can be directly compared with each other in terms of lens focal length. However, to facilitate comparisons in the characteristics, the so-called. EGF - focal length in 35 mm equivalent: this is the focal length that a lens for a full frame matrix having the same viewing angles would have. You can compare by EGF lenses for any matrix size. There are formulas that allow you to independently calculate the equivalent of 35 mm, they can be found in special sources.
If we talk about a specific specialization, then the EGF up to 18 mm corresponds to ultra-wide-angle fisheye lenses. Wide-angle is considered "fixed" optics with EGF up to 28 mm, as well as vario lenses with a minimum EGF up to 35 mm. Values up to 60mm correspond to "general purpose" optics, 50 - 135mm are considered optimal for shooting portraits, and higher focal lengths are found in telephoto lenses. More detailed information about the specifics of various focal lengths can be found in special sources.Optical zoom
The magnification factor provided by the camera by using the capabilities of the lens (namely, by changing its focal length). In models with interchangeable lenses (see “Camera type”), indicated for the complete lens, if available.
Note that in this case the magnification is indicated not relative to the image visible to the naked eye, but relative to the image produced by the lens at minimum magnification. For example, if the characteristics indicate an optical zoom of 3x, this means that at the maximum magnification, objects in the frame will be three times larger than at the minimum.
The degree of optical zoom is directly related to the range of focal lengths (see above). You can determine this degree by dividing the maximum focal length of the lens by the minimum, for example 360mm / 36mm=10x magnification.
To date, optical zoom provides the best "close" image quality and is considered to be superior to digital zoom (see below). This is due to the fact that with this format of work, the entire area of \u200b\u200bthe matrix is constantly involved, which allows you to fully use its capabilities. Therefore, even among low-cost models, devices without optical zoom are very rare.
Manual focus
Possibility of
manual focusing of camera optics. On the one hand, such focusing is more difficult than automatic focusing, as it requires unnecessary actions from the user, time consuming and increases the risk of spoiling the frame or missing the moment. On the other hand, this function allows the photographer to independently focus on the desired object, without relying on autofocus (which, for all the reliability of modern technology, may well not work as we would like).
Among digital compact cameras (see "Camera type"), manual focus is usually found in mid-range and high-end models that are intended for people who are familiar with the basics of photography. In devices with interchangeable lenses (reflex and "mirrorless", see ibid.), the type of focusing essentially depends on the characteristics of the lens, and not on the camera itself. But since there are very few lenses without manual focus (more often there are “only manual” models, without autofocus), it is generally accepted that cameras with
interchangeable lenses, by definition, support this function.
Connection ports
— USB C. A universal USB interface that uses a Type C connector. USB ports themselves (all types) are used mainly for connecting the camera to a computer for copying footage, managing settings, updating firmware, etc. Specifically The Type C connector is comparable in size to earlier miniUSB and microUSB, but has a reversible design that allows the plug to be inserted in either direction. In addition, USB C often operates according to the USB 3.1 standard, which allows for connection speeds of up to 10 Gbps - a useful feature when copying large amounts of content.
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HDMI. A comprehensive digital interface that allows you to transmit video (including high resolution) and audio (up to multi-channel) over a single cable. The presence of such a port makes it possible to use the camera as a player: it can be directly connected to a TV, monitor, projector, etc. and view your footage on the big screen. In this case, broadcast capabilities can include not only video playback, but also demonstration of captured photos in slide show mode. HDMI inputs are present in most modern video equipment, and connection is usually not a problem.
Nowadays, there are several versions of the HDMI interface on the market:
- v 1.4. The oldest version currently relevant, released in 2009. However, it supports 3D video, is capable of working with resolutions up to 4096x2160 at a speed of 24 fps, and in Full HD resolution the frame rate can reach 120...fps. In addition to the original v.1.4, there are also improved modifications - v.1.4a and v.1.4b; they are similar in basic capabilities, in both cases the improvements affected mainly work with 3D content.
- v2.0. Significant HDMI update introduced in 2013. In this version, the maximum frame rate in 4K has increased to 60 fps, and support for ultra-wide 21:9 format can also be mentioned. In update v.2.0a, HDR support was added to the interface capabilities; in v.2.0b this function was improved and expanded.
- v 2.1. Despite the similarity in name to v.2.0, this version, released in 2017, was a very large-scale update. In particular, it added support for 8K and even 10 K at speeds up to 120 fps, and also further expanded the capabilities for working with HDR. This version was released with its own cable - HDMI Ultra High Speed; all features of v.2.1 are available only when using cables of this standard, although basic functions can be used with simpler cords.
— Headphone output. Audio output allows you to connect headphones to the camera. As a rule, it is represented by a classic 3.5 mm mini-jack. The presence of such a connector provides the ability to monitor sound during video recording in real time. This is especially important when filming interviews, vlogs and other similar projects.
— Microphone input. Specialized input for connecting an external microphone to the camera. External microphones are significantly superior to built-in microphones in sound quality. Firstly, they are not so sensitive to the camera’s “own” sounds - from buttons, control wheels, focus motors, etc. (and if the microphone uses a long wire and is not attached to the body, these sounds will not be heard at all). Secondly, external microphones themselves have more advanced characteristics. On the other hand, their use is justified mainly for professional video recording; therefore, the presence of a microphone input, as a rule, corresponds to advanced video recording capabilities
Focus points
The number of focus points (autofocus) provided in the design of the camera.
The focus point is the point (more precisely, a small area) in the frame from which the autofocus system reads data for focusing. The simplest systems work with a single point, but their capabilities are very limited, and this option is practically not found today. Modern digital cameras have at least three focus sensors, and in the most advanced models this figure can reach several dozen.
The more autofocus sensors there are in the camera, the more advanced its autofocus capabilities will be, the more specific techniques it allows you to use. In this case, the selection of specific points used can be carried out both automatically, simultaneously with the choice of the subject program, and manually (however, the second option is more typical for professional cameras). In addition, the abundance of focus points has a positive effect on the quality of the tracking autofocus (see "Autofocus Modes").
In general, more focus sensors are generally considered a sign of a more advanced camera; however, differences in quality become really noticeable only if the difference in the number of points is significant - for example, if we compare models with 9 and 39 points. A lot also depends on the location of the points in the frame - it is believed that sensors distributed over a wide area work better than densely located in the center of the frame, even if their number is the same.
Shutter speed
The range of shutter speeds that the camera is capable of shooting.
Exposure is the time between opening and closing the shutter (see below), in other words, the period of time captured in the photo. For different purposes, methods and conditions of shooting, different shutter speeds will be optimal. Small values (in modern cameras they can reach thousandths of a second) are important when shooting fast-moving objects and for shooting at long distances — in the first case, they minimize the effect of image blur from the movement of the object, in the second — the effect of camera shake in hands. However, for shooting at low shutter speeds, a good matrix light sensitivity or high-aperture optics are required (see above). Long shutter speeds (measured in seconds) are used for shooting in low light conditions — such as city streets at night or the starry sky — and also allow you to create the effect of movement in the frame. Accordingly, the greater the shutter speed range, the wider the camera's ability to choose the option that is optimal for certain conditions.