Comparison DJI Tello vs Cheerson CX-10WD-TX

Maximum flight time of a quadcopter on one full battery charge. This indicator is quite approximate, since it is most often indicated for ideal conditions - in real use, the flight time may be less than stated. However, by this indicator it is quite possible to evaluate the general capabilities of the copter and compare it with other models - a longer declared flight time in practice usually means higher autonomy.

Note that for modern copters, a flight time of 20 minutes or more is considered a good indicator, and in the most “long-lasting” models it can exceed 40 minutes.

The highest speed that a quadcopter can achieve in horizontal flight. It is worth considering that in most cases this parameter is indicated for optimal operating conditions: a fully charged battery, low air temperature, minimum weight, etc. However, it is quite possible to rely on it both when choosing and when comparing different models of copters with each other.

Note that quadcopters were originally designed as stable and maneuverable aerial platforms, and not as high-speed vehicles. Therefore, you should specifically look for a fast quadcopter only in cases where the ability to quickly move from place to place is critical (for example, when the device is supposed to be used for video recording of fast-moving objects over large areas).

Resolution of the matrix in the standard camera of the quadrocopter.

Theoretically, the higher the resolution, the sharper, more detailed image the camera can produce. However, in practice, the quality of the "picture" is highly dependent on a number of other technical features - the size of the matrix, image processing algorithms, optical properties, etc. Moreover, when increasing the resolution without increasing the size of the matrix, the image quality may drop, because. significantly increases the likelihood of noise and extraneous artifacts. And for shooting video, a large number of megapixels is not required at all: for example, to shoot Full HD (1920x1080) video, which is considered a very solid format for quadrocopters, a sensor of only 2.07 megapixels is enough.

Note that high resolution is often a sign of an advanced camera with high image quality. However, this quality is not determined by the number of megapixels, but by the characteristics of the camera and the special technologies used in it. Therefore, when choosing a quadcopter with a camera, you should look not so much at the resolution as at the class and price category of the model as a whole.

The maximum resolution and frame rate supported by the aircraft camera when shooting in HD (720p).

HD 720p is the first high-definition video standard. Notably inferior to Full HD and 4K formats in terms of performance, it nevertheless provides pretty good detail without significant demands on the camera and processing power. Therefore, HD support is found even in relatively inexpensive copters. And in high-end models, it can be provided as an addition to more advanced standards.

In drones, HD cameras typically use the classic 1280x720 resolution; other, more specific options are practically non-existent. As for the frame rate, the higher it is, the smoother the video turns out, the less movement is blurred in the frame. In general, values up to 24 fps can be called minimal, from 24 to 30 fps — medium, from 30 to 60 fps — high, and speeds over 60 fps are used mainly for slow motion HD.

The viewing angle provided by the standard quadcopter camera; for optics with adjustable zoom, usually, the maximum value is taken into account.

The viewing angle is the angle between the lines connecting the centre of the lens to the two opposite extreme points of the visible image. Usually measured along the diagonal of the frame, but there may be exceptions. As for the specific values of this parameter, in modern copters they can range from 55 – 60 ° to 180 ° and even more. At the same time, a wider angle (ceteris paribus) allows you to simultaneously fit more space into the frame; and a narrower one covers a smaller space, however, the objects that are in the frame look larger, it is easier to see individual small details on them. So when choosing by this parameter, you should consider what is more important for you: wide coverage or an additional zoom effect.

Stabilization system built directly into the complete drone camera.

Any stabilization system is designed to compensate for vibrations and shaking, thus providing a stable image, without shaking and abrupt shifts in the camera. This feature slightly increases the cost of the device, but the quality of the video is noticeably improved. On the other hand, stabilization makes it difficult to perform complex manoeuvres, since when using it, feedback deteriorates: the change in the camera image does not quite correspond to changes in the position of the drone in space. Thus, in devices that have an acrobatic mode (see "Flight Modes"), such a system can be turned off.

Note that specifically in the camera, stabilization is most often carried out according to the electronic principle: a reserve space is allocated along the edges of the matrix, and during vibrations or shaking, the camera “pulls up” a fragment of the picture from this reserve, keeping the image in the frame motionless. This format of work somewhat reduces the useful area of the matrix, but it is inexpensive, does not affect the weight of the camera and does not complicate its design. Another option for compensating frame shifts is a mechanical gimbal stabilizer that uses a different principle of operation (see below); and some quadcopters provide both of these functions at once — this ensures maximum efficiency.

— Return home function. With this function, the quadcopter can automatically return to the starting point. The specific details of this feature may vary. So, some models return "home" at the user's command, others are able to do it on their own — for example, when the signal from the remote control is lost or when the battery charge is critically low; in many devices, both options are provided at once. Also note that this function is found even in models that do not have a GPS module (see "Sensors") — the copter can navigate in space in another way (by inertial sensors, by a signal from the remote control, etc.).

— Follow me mode. A mode that allows the quadcopter to constantly follow the user at a short distance — like a "personal drone". The way to implement this mode and the equipment required for it can be different: some models track the direction to the transmitter and the signal strength from it, others constantly receive data from the GPS module of a smartphone or other gadget and follow these coordinates, etc. Anyway, such a mode can be useful not only for entertainment, but also for quite practical purposes — for example, for using a quadcopter as an “air chamber”, constantly located next to the operator and at the same time not occupying hands.

— Dronie (distance). Initially, the term “dronie” refers to a selfie (photo or video) taken from a...drone. This mode is mainly intended for such tasks. And its essence lies in the fact that the copter smoothly moves away from a certain object along a given trajectory, keeping this object in the centre of the frame. The classic version of flying in Dronie mode is moving away first horizontally, then horizontally and up; however, in some models, the copter’s trajectory can be further configured. Frame management can also be carried out in different ways — from simple pointing at a certain point and ending with the selection of an object on the screen with further "smart" tracking of this object. Anyway, for all its simplicity, such a shooting technique allows you to create quite interesting videos: for example, in this way you can first capture a group of people in close-up in one video, then the beauty of the landscape around them.

— Rocket (distance up). A flight mode in which the copter smoothly rises to a predetermined altitude along a strictly vertical trajectory. Similar to the Dronie described above, it is mainly used when shooting video: first, a certain scene is shot in close-up, and as it rises, the camera covers an increasingly wider area around this scene. Usually, in Rocket mode, you can pre-set the height at which the device will stop.

— "Orbit mode" (flying in a circle). A mode that allows you to launch the copter in a circular orbit around the specified point. It is also used mainly for shooting video: in such cases, the camera remains constantly pointed at a given object, but the angle and background, due to the movement of the drone, are constantly changing. In the "orbit" settings, usually, you can set its radius, height and direction of movement, as well as the angle of the camera.

— Helix (circle in a spiral). Another mode used as an artistic technique for filming videos. In this mode, the copter, keeping a given object in the centre of the frame, moves around it in a spiral, gradually moving away and increasing its height. This allows you to get the maximum variety of angles and angles of coverage.

Note that Dronie, Rocket, Helix, and Orbit modes originally appeared as part of the proprietary QuickShot toolkit in DJI's Mavic series drones. However, later similar functions were introduced by other manufacturers, so now these names are used as common nouns.

— Flight plan(Waypoints). The ability to set a specific flight route for the quadcopter, by control points. This feature is very similar to the GPS waypoint flyby (see above), but it works differently, without the use of GPS navigation. One of the most popular options is building a route in the smartphone application through which the copter is controlled; when the programme is launched, the smartphone issues a sequence of commands corresponding to the route to the device. In general, the Waypoints mode is not as accurate as a GPS waypoint flyby and offers fewer options. Therefore, this function is mainly for entertainment purposes; if the copter has a camera, it can be useful for taking a selfie or a simple video.

— Flight by GPS points. A mode that allows you to launch a quadcopter along a specific route — by setting individual route points to the car in advance (according to GPS coordinates) and the order in which they are passed. In addition, additional settings may be provided — for example, speed and altitude on individual sections of the route. This function is similar to the Waypoints mode (see below) in many ways, but it is found mainly in mid-range and high-end devices. At the same time, the use of GPS provides higher accuracy, which allows the drone to be used for professional purposes. For example, if you set a route for shooting from the air in this way, the operator will be able to fully concentrate on working with the camera, without being distracted by controlling the copter.

— Acrobatic mode. A special mode for performing aerobatics. Note that the specific meaning of this mode may be different, depending on the level and purpose of the copter. So, in the simplest entertainment models, automatic programs are usually provided that allow you to perform certain aerobatic manoeuvres literally “at the touch of a button”. And in advanced devices in flight mode, the stabilization system is turned off, and the drone is very sensitive to operator commands; this requires high precision in control, but gives maximum control over the flight.

The control method provided in the copter.

Modern drones are usually controlled by a remote control, a smartphone, or both. Here is a detailed description of each of these options:

— Remote control only. Management carried out exclusively from the complete remote control. The most common option, found in all varieties of drones — from the simplest entertainment models to high-end professional devices; and heavy commercial / industrial models (see "Type") are completely controlled exclusively in this way. Such popularity is explained by two points. Firstly, the functionality of the remote control can be almost anything — from a small device with a couple of levers and buttons to a multifunctional control unit with a screen for live broadcasts and displaying various specialized information. Thus, the equipment of the remote control can be optimally matched to the features of a particular copter. Secondly, you can install a powerful transmitter with a large range in the remote control (whereas the range of smartphones is very limited, and it also depends on the specific gadget model). Well, besides, the control panel is initially supplied with the drone (except that the batteries in some models need to be purchased separately).

— Smartphone only. Management carried out exclusively from a smartphone (or other similar gadget — for example, a tab...let) through a special application; communication is usually carried out via Wi-Fi. This option is good because almost any functionality can be provided in the control application; and the copter itself turns out to be convenient in transportation — in the sense that you do not need to carry a separate remote control with it. However, the range in such a control is very small — even under perfect conditions, it usually does not exceed 100 m, and in some models it does not even reach 50 m; and the actual communication range also strongly depends on the characteristics of the control gadget. In addition, the controls on the touch screen are not tactile, making blind control almost impossible. As a result, this option is very rare — in certain models of mini-drones and selfie-drones (see "In the direction"), for which the absence of a remote control and ease of carrying are important, and the described disadvantages are not critical.

— Remote control and smartphone. The ability to control the drone both from the remote control and from a smartphone. The features of both options are described in detail above; and their combination is found mainly in relatively simple devices, for which the shortcomings of control via a smartphone are not critical (although there are exceptions). At the same time, the main option for such copters is often control from an external gadget, and the remote control may not be included at all; This point does not hurt to clarify before buying. However, anyway, this control format gives the user the opportunity to choose the best option for a specific situation. For example, for recreational flights during a "sally" in nature, you can get by with a smartphone, and for aerobatic training, a remote control is better. So most modern quadcopters that can be controlled from a smartphone / tablet fall into this category.

The range of the drone is the maximum distance from the control device at which a stable connection is maintained and the device remains controlled. For models that allow operation both from the remote control and from a smartphone (see "Control"), this item indicates the maximum value — usually achieved when using the remote control.

When choosing according to this indicator, note that the range is indicated for perfect conditions — within line of sight, without obstacles in the signal path and interference on the air. In reality, the control range may be somewhat lower; and when using a smartphone, it will also depend on the characteristics of a particular gadget. As for specific figures, they can vary from several tens of metres in low-cost models to 5 km or more in high-end equipment. At the same time, it should be said that the greater the range of communication, the higher its reliability in general, the better the control works with an abundance of interference and obstacles. Therefore, a powerful transmitter can be useful not only for long distances, but also for difficult conditions.