Maximum flight time
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.
Camera type
The type of camera installation that the quadcopter is equipped with.
- Built-in. A camera that is permanently installed on the vehicle and cannot be removed without disassembling the fuselage. This is the simplest option for tech who want to use a quadcopter for photo and video shooting or for flying with a first-person view (see “Real-time broadcast”); In addition, this camera design is considered more durable and reliable than a removable one. On the other hand, it does not make it possible to remove the camera to make the car lighter or replace it with another one that is more suitable in terms of characteristics.
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Removable. As the name suggests, such cameras are installed on detachable mounts. Thanks to this, the customer can remove or install the camera, depending on what is more important to him at the moment - the light weight of the car or the presence of an electronic “eye” on board. Note that in some models you can install not only a standard device, but also a third-party device.
- Absent.
Drones that are not equipped with cameras at all fall into two main categories. The first does not involve the use of any cameras at all; As a rule, it includes inexpensive devices primarily for entertainment purposes, for which the “peephole” is just an expensive and unnecessary excess, which also increases the weight of the entire structure. The second type is models with
...the ability to install a camera. It includes quite advanced copters - up to powerful professional machines capable of carrying a digital SLR. This option will be useful for tech who would like to independently select a camera to suit their needs. However, we note that the second type may have an auxiliary “eye” for live FPV broadcasts (see below); however, if such a “peephole” does not allow for taking photos/videos, it is not considered a full-fledged camera, and its presence is indicated only in additional notes. — Thermal imaging. A camera operating on the principle of a thermal imager - it detects infrared radiation from heated objects and forms a characteristic thermal image visible to the drone operator. Each color in this image corresponds to a specific temperature. A thermal imager equipped in a drone opens up possibilities not available to traditional optical cameras. Thus, it can be used to distinguish a person or animal against a camouflage background or in dense vegetation in an area. Thermal imaging cameras also “see” perfectly in complete darkness.
Quadcopters with a thermal imaging camera are by no means a cheap pleasure. They are used by rescuers, military, law enforcement, repairmen, hunters and fishermen. In particular, drones with a thermal imaging camera help find living people when clearing rubble, and are widely used to search for possible fires, gas leaks from pipelines, etc. In some situations, the performance of a thermal imager may be low - for example, it is not able to clearly identify an object if its temperature coincides with the background temperature (which makes it difficult to use in hot weather). In addition, the resolution and detail of the picture, even in advanced models, is quite modest. Thermal cameras in drones can be built-in or detachable.Number of megapixels
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.
HD filming (720p)
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.
Viewing angles
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.
Gesture control
The ability to control the copter with gestures.
The implementation of this function can be different. The simplest and most inexpensive option is smartphone control, when commands are given by turning and tilting the gadget. There are models where the accelerometer and gyroscope are built directly into the remote control, and you can control it with hand gestures with the remote control. Another, more expensive and original way is to recognize the position of the user's hands using the built-in camera. Such devices usually have a set of commands tied to rather specific movements. For example, by folding your fingers into a “frame”, you can turn on the burst photography mode, with a wave of your hand you can call to yourself, and the device will perceive the outstretched palm as a landing pad.
In general
, gesture control provides at least additional entertainment, and in some cases can be useful from a practical point of view.
Range
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.
Video transmission frequency
The frequency of the radio channel used to transmit the video stream from the camera on board the drone to the receiving device: smartphone or tablet, control panel or pilot’s video glasses. The most common frequencies are 2.4 GHz and 5.8 GHz; video data transmission at a frequency of 1.2 GHz is less common. This parameter directly affects the quality and stability of the video signal, depending on environmental conditions, as well as accompanying interference from other devices. Thus, for receiving video from FPV drones, the most preferable frequency is 5.8 GHz, which is due to a wide selection of channels and high data transfer rates.
Remote control power source
The number and type of batteries used in the quadcopter control panel.
— AA. Replaceable batteries, colloquially known as "AA batteries". They are available not only in the form of disposable batteries, but also in the form of rechargeable batteries, are produced under various brands that differ in price and quality (which provides freedom of choice), and finding such elements on the market is usually not a problem. The power and capacity of AA elements are relatively small, but in most cases they are quite enough for normal operation of the transmitter for quite a long time. Usually, modern consoles require several of these batteries; in the most high consumption this number can reach 8.
— AAA. Also known as "pinky". In fact, a smaller version of popular AA elements (see above); has the same key features, but differs in more compact dimensions and, as a result, somewhat reduced power. This option is typical for low-cost class models, with a small range of the remote control.
— 3s. This marking does not describe the size of the battery, but its operating voltage and technology. It denotes a lithium-ion or lithium-polymer battery (see "Battery type"), assembled from three cells with a standard voltage of 3.7 V each, and thereby delivering an operating voltage of 11.1 V. The advantages of such a power supply are high power and capacity, which allows you to use the remote control for a long time without recharging. At the same time, batteries of thi...s type can vary significantly in size and weight, and not every model marked 3s will be compatible with the remote control. In addition, finding a spare battery is more difficult than a set of cells of a standard size.
— Proprietary battery. Powered by an original battery that is not related to any of the options described above. Such batteries can be much more powerful than replacement cells, making them well suited even for remotes with high power consumption. Their main advantage is the difficulty with quick replacement: the design of the remote control is at best poorly suited for this, and at worst the battery is generally non-removable. Also, finding the right replacement battery can be a major hassle.