Comparison Oukitel WP27 256 GB / 12 GB vs Hotwav Cyber X Pro 256 GB / 12 GB

Characteristics of the main (and most often the only) display installed in the device.

In addition to the basic properties - such as size, resolution (according to it, screens are conventionally divided into HD, Full HD, 2K and more), sensor type (most often IPS, OLED, AMOLED, Super AMOLED, Dynamic AMOLED,), this list can more specific features. Among them are the shape of the surface ( flat or curved), the presence and version of the Gorilla Glass coating (including the top v6 and Victus), HDR support and the refresh rate (a frequency on top 60 Hz is considered high, namely 90 Hz, 120 Hz and 144 Hz) . Here is a more detailed description of the characteristics relevant to modern displays:

- Size. Traditionally, the screen size is indicated in inches. A larger display is more convenient to use: more information is placed on i...t, and the image itself is better readable. The downside of increasing the size is an increase in the dimensions of the device. Today, smartphones with screens of 5" or less are considered small. 5.6 - 6" and up to 6.5" is already a medium format. Also, many modern models have a size of 6.5". Classic phones without touch screens do not need a large size - in them it usually does not exceed 3".

- Permission. Screen resolution is specified based on its vertical and horizontal dimensions in dots (pixels). The larger these dimensions (with the same size) - the more detailed and smoothed the picture looks and the less individual pixels are visible on it. On the other hand, increasing the resolution increases both the cost of the display itself and the requirements for the phone's hardware. It is also worth noting that the same resolution on screens of different sizes looks different; so when evaluating detail, it is worth considering not only this parameter, but also the PPI number (see below).

— PPI. The density of dots (pixels) on the screen of the device. It is indicated by the number of dots per " (points per ") - the number of pixels for each horizontal or vertical segment of 1 ". This indicator depends both on the size and resolution, but in the end it is the PPI number that determines how smooth and detailed the image on the display is. For comparison, we note that at a distance of about 25 - 30 cm from the eyes, a density of 300 PPI or more makes individual pixels almost invisible to a person with normal vision, the picture is perceived as a complete one; at greater distances, a similar effect is noticeable at a lower point density.

— Matrix type. The technology by which the screen sensor is made. This parameter is indicated only for relatively advanced displays that are superior in performance to the simplest LCD screens of push-button phones. The most widespread in our time are the following types of matrices:

• IPS. The most popular technology for the screens of modern smartphones. It provides a very decent image quality, viewing angles and response speed, although it is somewhat inferior in these parameters to many more advanced options (see below). On the other hand, IPS also has important advantages: durability, uniform wear, and also a rather low cost. Thanks to this, such screens can be found in all categories of smartphones - from low-cost to top-end.
• AMOLED. Organic light-emitting diode (OLED) sensor technology developed by Samsung. One of the key differences between such matrices and more traditional displays is that they do not require external illumination: each pixel is its own light source. Because of this, the power consumption of such a screen depends on the characteristics of the displayed image, but in general it turns out to be quite low. In addition, AMOLED matrices are distinguished by wide viewing angles, excellent brightness and contrast ratios, high color reproduction quality and fast response time. Due to this, such screens continue to be used in modern smartphones, despite the emergence of more advanced technologies; they can be found even in top-end models. The main disadvantage of this technology is the relatively high cost and uneven wear of the pixels: dots that work longer and more often at high brightness burn out faster. However, usually this effect becomes noticeable only after several years of intensive use - a period comparable to the operational resource of the smartphone itself.
• AMOLED (LTPO). An advanced version of AMOLED panels with the ability to dynamically adjust the refresh rate depending on the tasks performed. The abbreviation LTPO stands for Low Temperature Polycrystalline Oxide. Behind this term is a combination of traditional LTPS technology and a thin layer of TFT oxide film with the addition of hybrid-oxide polycrystalline silicon to drive the sweep switching circuits. AMOLED panels (LTPO) reduce the energy consumption of the gadget by an order of magnitude. So, when performing active actions, the device screen uses the maximum or high refresh rate, and while viewing pictures or reading text, the display reduces the rate to a minimum.
• Super AMOLED. An improved version of the AMOLED technology described on top One of the key improvements is that in Super AMOLED screens there is no air gap between the touch layer and the display located under it. This made it possible to further increase the brightness and image quality, increase the speed and reliability of the sensor response and at the same time reduce power consumption. The disadvantages of such matrices are the same as the original AMOLED. In general, they are quite widespread; most smartphones with similar screens belong to the middle and top categories, but there are also low-cost models.
• OLED. Various types of matrices based on the use of organic light emitting diodes; in fact - analogues of AMOLED and Super AMOLED, produced not by Samsung, but by other companies. The specific features of such screens may be different, but for the most part they are, on the one hand, more expensive than popular IPS, on the other hand, they provide higher image quality (including brightness, contrast, viewing angles and color fidelity), and also consume less energy and have small thickness. The main disadvantages of OLED screens are the high price (which, however, is constantly decreasing as the technology develops and improves), as well as the susceptibility of organic pixels to burn-in when broadcasting static images for a long time or images with static elements (notification panel, on-screen buttons, etc.). ).
• OLED (polymer). Organic Light-Emitting Diode (OLED) screens, which do not use glass as a base, but a transparent polymer material. We emphasize that we are talking about the basis of the sensor; from on top it is covered with the same glass as in other types of screens. However, this design offers a number of advantages over traditional "glass" matrices: it provides additional impact resistance and is great for creating curved displays. On the other hand, in terms of optical properties, plastic still falls short of glass; so screens of this type are often inferior in image quality to their “peers” made using traditional OLED technology, and with a similar picture quality, they are noticeably more expensive.
• OLED (LTPO). OLED-matrices with adaptive refresh rate, which can be changed in a wide range based on the tasks performed. In games, screens with LTPO technology automatically raise the refresh rate to the maximum values, while viewing static images, they reduce it to a minimum (from 1 Hz). At the heart of the technology is a traditional LTPS substrate with a thin TFT oxide film on top of the TFT base. The ability to control the flow of electrons provides dynamic control over the refresh rate. The competitive advantage of OLED (LTPO) is reduced power consumption.

In addition, screens in modern smartphones can be made using the following technologies:

• pls. A variation of IPS technology created by Samsung. In some respects - in particular, brightness, contrast and viewing angles - it surpasses the original, while it is cheaper to manufacture and allows you to create flexible displays. However, for a number of reasons, it is not particularly popular.
• Super AMOLED Plus. A further development of the Super AMOLED technology described on top. Allows you to create even brighter, more contrasting and at the same time thin and energy-efficient screens. However, most often such screens in our time are simply referred to as "Super AMOLED", without the "Plus" prefix.
• Dynamic AMOLED. Another AMOLED improvement introduced in 2019. The main features of such matrices are increased brightness without a significant increase in power consumption, as well as 100% coverage of the DCI-P3 color space and compatibility with HDR10 +; the last two points, in particular, make it possible to reproduce modern high-low-cost cinema on such screens with the highest quality. The main disadvantage of Dynamic AMOLED is traditional - the high price; so such matrices are found mainly in top models.
• Super Clear TFT. A joint development by Samsung and Sony, which appeared as a forced alternative to Super AMOLED matrices (the demand for them at one time significantly exceeded production capabilities). True, the image quality of Super Clear TFT is somewhat lower - but in production such matrices are noticeably simpler and cheaper, but in terms of performance they still surpass most IPS screens. However, in our time, this technology is rare, giving way to AMOLED in different versions.
• super LCD. Another alternative to various kinds of AMOLED technology; used mainly in HTC smartphones. Similar to Super AMOLED, such screens do not have an extra air gap, which has a positive effect on both image quality and the clarity of sensor responses. A notable advantage of the Super LCD is its good power efficiency, especially when displaying bright whites; but in terms of overall color saturation (including black), this technology is noticeably inferior to AMOLED.
• LTPS. An advanced type of TFT matrices, created on the basis of the so-called. low temperature polycrystalline silicon. It allows you to easily create screens with a very high pixel density (more than 500 PPI - see on top), achieving high resolutions even with a small size. In addition, part of the control electronics can be built directly into the sensor, reducing the overall thickness of the display. The main disadvantage of LTPS is the relatively high cost, but nowadays such screens can be found even in low-cost smartphones.
• S-PureLED. A technology developed by Sharp and used primarily in its smartphones. Actually, the technology of the matrices themselves in this case is called S-CG Silicon TFT, and S-PureLED is the name of a special layer used to increase transparency. S-CG Silicon TFT is positioned by the creators as a modification of the LTPS technology described on top, which allows to further increase the resolution of the display and at the same time build more control electronics into it (up to a whole “processor on glass”) without increasing the thickness. Of course, these screens are not cheap.
• e-ink. Matrices based on the so-called "electronic ink" - a technology common primarily in electronic books. The main feature of such a screen is that during its operation, energy is spent only on changing the image; a still picture does not require power and can remain on the display even in the absence of power. In addition, by default, E-Ink matrices do not glow on their own, but reflect outside light - so their own backlight is not necessary for them (although it can be provided for work at dusk and darkness). All this provides a solid energy savings; and for some users, such screens are purely subjectively more comfortable and less tiring than traditional matrices. On the other hand, E-Ink technology also has serious drawbacks - first of all, a long response time, as well as the complexity and high cost of color displays, combined with poor color reproduction quality on them. In light of this, in smartphones, such matrices are a very rare and exotic option.

— Sweep frequency. The maximum display refresh rate, in other words, the highest frame rate that it can effectively reproduce. The higher this figure, the smoother and smoother the image is, the less noticeable the “slideshow effect” and blurring of objects when moving on the screen. At the same time, it should be borne in mind that the refresh rate of 60 Hz, supported by almost any modern smartphone, is quite sufficient for most tasks; even high-definition videos hardly make use of high frame rates these days. Therefore, the scanning frequency in our catalog is specially specified mainly for screens capable of delivering more than 60 Hz (in some models - up to 240 Hz). Such a high frequency can be useful in games and some other tasks, it also improves the overall experience of the OS interface and applications - moving elements in such interfaces move as smoothly as possible and without blurring.

HDR. A technology that allows you to expand the dynamic range of the screen. In this case, the range of brightness is implied - simply put, the presence of HDR allows the screen to display brighter whites and darker blacks than on displays without support for this technology. In practice, this gives a noticeable improvement in image quality: the saturation and reliability of the transmission of various colors improves, and the details in very light or very dark areas of the frame do not “sink” in white or black. However, all these advantages become noticeable only on the condition that the content being played is originally recorded in HDR. Nowadays, several varieties of this technology are used, here are their features:

• HDR10. Historically the first of the consumer HDR formats, it is extremely popular today: in particular, it is supported by almost all streaming services with HDR content and is standardly used for such content on Blu-ray discs. Provides a color depth of 10 bits (more than a billion shades). At the same time, HDR10+ format content (see below) can also be played on devices with this technology, except that its quality will be limited by the capabilities of the original HDR10.
• HDR10+. An improved version of HDR10. With the same color depth (10 bits), it uses the so-called dynamic metadata, which allows transmitting information about the color depth not only for groups of several frames, but also for individual frames. This results in an additional improvement in color reproduction.
• Dolby vision. An advanced standard used particularly in professional cinematography. It allows you to achieve a color depth of 12 bits (almost 69 billion shades), uses the dynamic metadata mentioned on top, and also makes it possible to transmit two image options at once in one video stream - HDR and normal (SDR). At the same time, Dolby Vision is based on the same technology as HDR10, so in modern electronics this format is often combined with HDR10 or HDR10 +.

- DC Dimming support. Literally from English, Direct Current Dimming is translated as direct current dimming. This technology is designed to minimize flicker in OLED and AMOLED screens, which, in turn, reduces the load on the user's visual apparatus and protects eyesight. The “flicker-free” effect is achieved by directly controlling the brightness of the backlight LEDs by changing the voltage applied to them. Due to this, a decrease in the intensity of the glow of the screen is ensured.

- Curved screen. A screen that has curved edges to which the displayed image extends. In other words, in this case, not only glass is curved, but also part of the active sensor. Displays where both edges are curved are sometimes referred to as "2.5D glass" as well; also there are devices where the screen is bent only on one side. In any case, this feature gives the smartphone an interesting appearance and improves the visibility of the image from some angles, but it significantly affects the cost and can create inconvenience when holding (especially without a case). So before buying a model with such equipment, ideally, you should hold the device in your hand and make sure that it is comfortable enough.

- Gorilla Glass. Special high-strength glass used as a display cover. It is characterized by endurance and resistance to scratches, many times superior to ordinary glass in these indicators. It is widely used in smartphones, where large screen sizes put forward increased requirements for coverage reliability. Modern phones may have different versions of this glass, here are the features of different options:

• Gorilla Glass v3. The oldest of the current versions is released in 2013; now found mainly among inexpensive or obsolete devices. However, this coating also has undoubted advantages: this is the first generation of Gorilla Glass, where the creators have made a noticeable emphasis on resistance to scratches from keys, coins and other objects that the phone can “collide” in a pocket or bag. In this respect, the v3 version remained unsurpassed until the release of Gorilla Glass Victus in 2020.
• Gorilla Glass v4. Version released in 2014. A key feature was that the development of this coating focused on impact resistance (whereas previous generations focused mainly on scratch resistance). As a result, the glass is twice as strong as in version 3, despite the fact that its thickness is only 0.4 mm. But here's the scratch resistance, compared with its predecessor, has decreased slightly.
• Gorilla Glass v5. A gorilla improvement released in 2016 to further improve impact resistance. According to the developers, the glass of the v5 version is 1.8 times stronger than its predecessor, remaining intact in 80% of drops from a height of 1.6 m "face down" on a rough surface (and guaranteed impact resistance is 1.2 m). Scratch resistance has also improved somewhat, but this material still falls short of v3 performance.
• Gorilla Glass v6. Version introduced in 2018. For this coating, a 2-fold increase in strength compared to its predecessors is claimed, as well as the ability to endure multiple drops on a hard surface (in tests, v6 glass successfully endured 15 drops from a height of 1 m). The maximum drop height (single) with guaranteed integrity is declared at 1.6 m. Scratch resistance has received practically no improvement.
• Gorilla Glass 7. Original name for Gorilla Glass Victus - see below.
• Gorilla Glass Victus. The "heir" of Gorilla Glass 6, released in the summer of 2020. In this coating, the creators paid attention not only to increasing the overall strength, but also to improving scratch resistance. According to the latter indicator, Victus surpasses even the v3 version, not to mention more sensitive materials (and compared to v6, scratch resistance is claimed to be twice as high). As for durability, it allows you to guarantee to endure single drops from a height of up to 2 m, as well as up to 20 consecutive drops from a height of 1 m.

The maximum brightness in nits provided by the smartphone display.

The brighter the display, the more readable the picture remains on it under intense ambient light (for example, outdoors on a clear sunny day). Also, high brightness is important for the correct displaying of HDR content. However, a large amount of brightness affects the cost and power consumption of the screen. Manufacturers can specify standard, maximum, and peak brightness values. At the same time, an equal sign cannot be put between the maximum and peak brightness. The first indicates the ability of the screen to produce the specified brightness over its entire area, while the peak one — in a limited area and for a short time (mainly for HDR content).

The ratio of the screen area to the total front panel area of the phone. Simply put, this spec describes how much of the front panel is occupied by the screen; the rest is the bezels.

This indicator is given exclusively for smartphones with touch screens — it is for them that it is most relevant. The larger the percentage of the body is occupied by the screen, the thinner are the bezels, the neater the smartphone looks and the more convenient it is to work with it with one hand. As for specific numbers, the average values are 80 – 85 %, the higher values allow us to talk about a thin bezel, and more than 90 % — about a “bezel less” design.

Separately, we note that this parameter has nothing to do with the aspect ratio of the screen. The aspect ratio describes only the display itself — its proportions, the ratio between the larger and smaller side of the rectangle.

The type of the phone's storage.

The specification determines, first of all, the speed of the memory, and, accordingly, the performance of the device as a whole (especially when working with large amounts of data or resource-intensive applications). Nowadays, there are two basic specifications — eMMC and UFS; each of them has several versions. In general, storages with UFS 3.1 and UFS 4.0 are the fastest and most advanced today, but they cost accordingly, and therefore are used mainly in premium smartphones. A more detailed description of these standards looks like this:

— eMMC. One of the simplest and most affordable standards for solid state memory — for example, this specification is used by most flash drives. In smartphones and other portable gadgets, this standard was generally accepted until 2016, when the introduction of UFS began; however, even now it is very popular — mainly due to its low cost and low power consumption. But the speeds of eMMC are noticeably lower than those of UFS. So, in the latest version of eMMC 5.1A (2019), the read speed is up to 400 MB/s, and the earlier and more common version of eMMC 5.1 provides up to 250 MB/s in read mode, up to 125 MB/s in sequential write mode and all only up to 7.16 MB/s with random writes (in other words, in application mode).

— UFS. A solid state drive standard designed to be a faster, more advanced successor to eMM...C. In addition to the increased data exchange speeds, the format of work has also been changed in UFS — it is fully duplex, that is, reading and writing can be performed simultaneously (whereas in eMMC these processes were performed in turn). Also, efficiency in random read and write mode has been significantly improved, which has a positive effect on the quality of work with applications. Specific data exchange rates and features of work depend on the version of UFS, nowadays you can find the following options:

• 2.0. The earliest of the versions found in modern smartphones; was released back in 2013. Provides data transfer rates up to 1.2 GB/s, the maximum available in this version. The newer version 2.1 has the same speeds, but it is supplemented with a number of important innovations. Therefore, UFS 2.0 memory is rarely used in mobile phones.
• 2.1. The first of the versions that are widely used in smartphones; was released in 2016. In terms of speed, it does not differ from version 2.0 described above, and the main differences are in some improvements. In particular, UFS 2.1 introduced storage status indicator (“health”), the ability to remotely update the firmware, as well as a number of solutions aimed at improving overall reliability.
• 2.2. An evolution of the UFS 2.x standard introduced in Summer 2020. A key improvement is the introduction of the WriteBooster feature (originally introduced in UFS 3.1); this feature allows you to significantly increase the write speed and, accordingly, the overall performance in tasks like running applications.
• 3.0. A version released in 2018 and implemented in hardware a year later. The throughput was increased to 2.9 GB/s per two lines (1.45 GB/s per one), new versions of the M-PHY electronic protocol (physical layer) and UniPro based on it were introduced, the reliability of working with data and the temperature mode of operation of the controllers has been expanded (theoretically, it can range from -40 °С to 105 °С). UFS 3.0 is used mainly in fairly advanced smartphones, although in the future we can expect this specification to be extended to more modest models.
• 3.1. The successor to the UFS 3.0 standard, officially introduced in early 2020. It is positioned as a specification created specifically for high-performance mobile devices and aimed at increasing speed while minimizing power consumption. To do this, UFS 3.1 has a number of innovations: a non-volatile Write Booster cache to speed up writing; special DeepSleep power saving mode for relatively simple and inexpensive systems; as well as the Performance Throttling Notification feature, which allows the drive to send overheating signals to the control system. In addition, this standard may additionally provide support for the HPB extension, which improves reading speed.
• 4.0. UFS 4.0 doubled the throughput per lane (23.2 Gbps per lane) and improved energy efficiency by about 46% (compared to the previous 3.1 specification). UFS 4.0 standard memory modules provide maximum read speed up to 4200 MB/s, write speed up to 2800 MB/s. The high bandwidth makes the memory standard ideal for 5G smartphones.

Specifications of the main lens of the rear camera installed in the phone. In models with several lenses (see “Number of lenses”), the main one is responsible for basic shooting capabilities and does not have a pronounced specialization (wide-angle, telephoto, etc.). Four main parameters can be indicated here: resolution, aperture ( high aperture optics are quite common), focal length, additional sensor data.

Resolution(in megapixels, MP)
Resolution of the sensor used for the main lens. Budget options are equipped with a module 8 MP and below, many models have 12 MP camera / 13 MP, also recently a trend towards increasing megapixels has been popular. Often in smartphones you can find the main photomodule at 48 MP, 50 MP< /a>, 64 MP and even 108 MP .

The maximum resolution of the resulting image directly depends on the resolution of the sensor; and the high resolution of the "picture", in turn, allows you to better display fine details. On the other hand, an increase in the number of megapixels in itself can lead to a deterioration in the overall image quality - due to the smaller size of each individual pixel, the noise level increases. As a result,...the direct resolution of the camera has little effect on the quality of the shooting - more depends on the physical size of the matrix, the features of the optics and various design tricks used by the manufacturer.

Aperture
Aperture describes the ability of a lens to transmit light. It is written as a fractional number, for example f/1.9. Moreover, the larger the number in the denominator, the lower the aperture ratio, the less light passes through the optics, all other things being equal. For example, an f/2.6 lens will be “darker” than f/1.9.

High aperture gives the camera a number of advantages. First, it improves the quality of shooting in low light. Secondly, it's possible to shoot at low shutter speeds, minimizing the effect of "stirring" and blurring of moving objects in the frame. Thirdly, with fast optics it is easier to achieve a beautiful background blur ("bokeh") — for example, when shooting portraits.

Focal length(in millimetres)
The focal length is a distance between the sensor and the centre of the lens (focused to infinity), at which the most clear image is obtained on the matrix. However, for smartphones, the specifications indicate not the actual, but the so-called equivalent focal length — a conditional indicator recalculated using special formulas. This indicator can be used to evaluate and compare cameras with different sensor sizes (the actual focal length cannot be used for this, since with a different sensor size the same real focal length will correspond to different viewing angles). (It is also worth saying that the equivalent focal length can be noticeably larger than the thickness of the case — there is nothing unusual in this, since this is a conditional, and not a real indicator).

Anyway, the field of view and the degree of magnification directly depend on the equivalent focal length: a larger focal length gives a smaller field of view and a larger size of individual objects that fall into the frame, and a decrease in this distance, in turn, allows you to cover more space. In most modern smartphones, the focal length of the main camera ranges from 13 to 35 mm; if compared with the optics of traditional cameras, then lenses with equivalent focal length up to 25 mm can be attributed to wide-angle lenses, more than 25 mm — to universal models “with a bias towards wide-angle shooting”. Such values are chosen due the fact that smartphones are often used for shooting in cramped conditions, when a fairly large space needs to fit into the frame at a small distance. Enlargement of the picture, if necessary, is most often carried out digitally — due to the reserve of megapixels on the sensor; but there are also models with optical zoom (see below) — for them, not one value is given, but the entire working range of the equivalent focal length (recall, optical zoom is carried out by changing the focal length).

Field of view(in degrees). It characterizes the size of the area covered by the lens, as well as the size of individual objects "seen" by the camera. The larger this field, the more of the scene gets into the frame, but the smaller the individual objects in the image are. The field of view is directly related to the focal length (see above): increasing this distance narrows the field of view of the lens, and vice versa.

Note that this parameter is generally considered important for professional use of the camera rather than for amateur photography. Therefore, viewing angle data is given mainly for smartphones equipped with advanced cameras — including in order to emphasize the high class of cameras. As for specific values, for the main lens they usually are in the range from 70° to 82° — this corresponds to the general specifics of such optics (universal shooting with an emphasis on general scenes and extensive coverage at short distances).

Additional Sensor Data
Additional information regarding the sensor installed in the main lens. This item can specify both the size (in inches) and the sensor model, and sometimes both parameters at once. Anyway, such data is provided only if the device is equipped with a high-end sensor. With the model, everything is quite simple: knowing the name of the sensor, you can find detailed data on it. The size is worth considering a little more.

The size of the sensor is traditionally indicated in fractional parts of an inch — accordingly, for example, a 1/2.3" sensor will be larger than 1/2.6". Larger sensors are considered more advanced, as they provide better image quality at the same resolution. The logic here is simple - due to the large sensor area, each individual pixel is also larger and gets more light, which improves sensitivity and reduces noise. Of course, the actual image quality will also depend on a number of other parameters, but in general, a larger sensor size usually means a more advanced camera. In advanced photo flagships, you can find matrices with a physical size of 1”, which is comparable to image sensors used in top compact cameras with fixed lenses.

Specs of the ultra wide-angle lens of the main camera installed in the phone.

These details are relevant only for cameras with several lenses (see "Number of lenses") — and not all, but only those where there is a lens with a small focal length (much less than in the main lens) and, accordingly, wider viewing angles. It is called ultra-wide. In the same paragraph, four main parameters can be indicated: resolution, aperture ratio, focal length and additional sensor data.

Resolution(in megapixels, MP)
The resolution of the sensor used for the ultra-wide lens.

The maximum resolution of the resulting image directly depends on the resolution of the sensor; and the high resolution of the "picture" allows you to capture small details better. On the other hand, an increase in the number of megapixels in itself can lead to a deterioration in the overall image quality — due to the smaller size of each individual pixel, the noise level increases. As a result, the direct resolution of the camera has little effect on the quality of photos and videos — a lot also depends on the size of the sensor, the features of the optics and various design tricks used by the manufacturer. At the same time, we note that the more megapixels a camera has, the more likely it is to implement various additional solutions aimed at improving image quality.

As for the specific resolution of ultra-wide optics, it can co...rrespond to the number of megapixels in the main lens (see "Main lens") or be lower, sometimes quite noticeable (for example, 8 MP with the main optics at 48 MP). This is due to the fact that an ultra-wide-angle lens often plays a secondary role, for which a small resolution is more than enough.

Aperture
Aperture describes the ability of a lens to transmit light. It is written as a fractional number, for example f/1.9. Moreover, the larger the number in the denominator, the lower the aperture ratio, that is, for example, an f/2.6 lens will transmit less light than f/1.9.

High aperture gives the camera a number of advantages: it allows you to shoot at low shutter speeds, minimizing the likelihood of “shake”, and also makes it easier to shoot in low light and shoot with artistic background blur (bokeh). However, for an ultra-wide lens, such features are not as important as for the main camera — such lenses usually have a specific purpose, and their small aperture is often more desirable, which allows you to increase the depth of field. So in general, this parameter is more of a reference than practically significant when choosing.

Focal length
The focal length is a distance between the sensor and the centre of the lens (focused to infinity), at which the most clear image is obtained on the sensor. However, for smartphones, the specifications indicate not the actual, but the so-called equivalent focal length — a conditional indicator recalculated using special formulas. This indicator can be used to evaluate and compare cameras with different sensor sizes (the actual focal length cannot be used for this, since with a different sensor size the same real focal length will correspond to different viewing angles).

Anyway, the viewing angle and the degree of magnification directly depend on the equivalent focal length: a larger focal length gives a smaller viewing angle and a larger size of individual objects that fall into the frame, and a decrease in this distance, in turn, allows you to cover more space. Ultra-wide optics, by definition, must have very short focal lengths — smaller than the corresponding main optics. However, "ultra-wide" focal lengths typically range from 13 mm to 26 mm; such values are not rare among the main lenses. At the same time, there is nothing illogical here — the point is the ratio of focal lengths in each individual smartphone. For example, a camera with a 25mm primary lens can carry a 16mm or 17mm ultra-wide lens; and models with a primary lens less than 24mm usually do not have additional ultra-wide optics at all, since the existing lens perfectly plays this role just fine. Also note that the difference between these types of optics is not as significant as one might imagine; and in some devices, both focal lengths are generally the same, while the difference in specialization is achieved due to the features of image processing in each lens.

Field of view(in degrees) It is the size of the area covered by the lens, as well as the size of individual objects "seen" by the camera. The larger this angle, the more of the scene gets into the frame, but the smaller the individual objects in the image are. The field of view is directly related to the focal length (see above): increasing this distance narrows the field of view of the lens, and vice versa.

Note that this parameter is generally considered important for professional use of the camera rather than for amateur photography. Therefore, the field of view data is given mainly for smartphones equipped with advanced cameras — including in order to emphasize the high class of cameras in this way. As for specific values, ultra-wide-angle optics, by definition, have very wide angles — from 107° and above; in some models, this figure reaches 125°.

Additional Sensor Data
Additional information regarding the sensor installed in the ultra-wide lens. This item can specify both the size (in inches) and the sensor model, and sometimes both parameters at once. Anyway, such data is provided only if the device is equipped with a high-class sensor. With the model, everything is quite simple: knowing the name of the sensor, you can find detailed data on it. The size is worth considering a little more.

The size of the sensor is traditionally indicated in fractional parts of an inch — accordingly, for example, a 1/3.1" sensor will be larger than 1/4". Larger sensors are considered more advanced, as they provide a better image at the same resolution. This is due to the fact that due to the larger sensor area, each individual pixel is also larger and receives more light, which improves sensitivity and reduces noise. Of course, the actual image quality will also depend on a number of other parameters, but in general, a larger sensor size usually means a more advanced camera. However, in ultra-wide lenses, the sensors are generally noticeably smaller than in the main ones — for example, the mentioned 1/3.1" and 1/4" are quite common options. This is primarily due to the secondary role of such cameras.

Specs of the additional lens installed in the device.

An additional lens is the one that is not covered by any of the three categories described above (main, tele-, ultra-wide), but is used directly for taking photos and videos (that is, it is not an auxiliary one — see below). In this case, the specific purpose of such a lens may be different. In some models, modules for a specific purpose are installed — for example, "portrait" optics with a longer focal length than the main module (however, less than that of a telephoto lens). In other devices, you can find additional modules of standard specialization — for example, the second telephoto lens, which differs in specs from the main one; data on such modules is also given here.

The meaning of particular specifications is described in detail above, in the paragraphs regarding the main lens, telephoto lens and ultra-wide optics. Here we note some nuances that directly relate to additional modules or are worth re-mentioning:

• Resolution (in megapixels, MP). In itself, high resolution only increases the detail and does not necessarily improve the quality of the picture. However, numerous MPs is often a sign of an advanced camera, where various additional solutions are used to improve quality.
• Aperture. Written as a fraction, such as f/1.9; the larger the number in the designation, the lower the aperture ratio and the worse the light transmission of the lens. These optics are more expensive, but...offer better image quality and more overall performance.
• Focal length. Specified in millimetres. Directly affects the viewing angle and specialization of the lens: short focal lengths are typical for "wide-angle" and lenses for general use, significant — for "portrait" and telephoto lenses.
• Sensor size. Specified in fractions of an inch, such as 1/2.8". A larger sensor is more expensive and takes up more space, but provides better image quality.
• OIS. An abbreviation for "optical image stabilization". See below for more details on such systems, but here we note that they are typical mainly for advanced cameras: optical stabilization is more complicated and expensive than digital, but more effective.

The presence of an auxiliary lens in the module of the main (rear) camera of the smartphone. Common to all auxiliary lenses is that they themselves do not shoot, but only supply the main camera with some useful additional data. But the types of this data and, accordingly, the methods of using auxiliary cameras can be different.

So, in some smartphones, an additional lens of a very small resolution is installed, which is used to obtain special information about the depth of field in some shooting modes (primarily in portrait mode). This format of work gives a number of interesting features — in particular, it allows you to change the depth of focus on an already finished image, moving the focus to a particular subject. Another interesting option is the so-called ToF (time of flight) cameras, which work on the principle of rangefinders and are capable of creating 3D models of various objects (including reading facial expressions from the user's face). There are other options, such as a black-and-white secondary camera for greater dynamic range and a fast aperture for better low-light performance.

The presence of a macro lens in a smartphone. In some models, this feature is performed by a separate specialized lens, in others — by the lens of the main camera, which operates in a special mode.

Macro photography, for which such lenses are used, is a special mode that allows you to get very large and detailed images of miniature objects (for example, dew drops or a small insect). This mode is most often used as an artistic tool, but it can also be useful for other purposes, such as scientific ones. And the presence of a full-fledged macro lens means that the smartphone has quite advanced capabilities for such shooting. At the same time, the main camera is considered a macro lens only if it is capable of performing macro photography from a distance of 3 cm or less.