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.
Horizontal speed
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).
Ascent / descent speed
The speed at which the quadcopter rises up in the air or descends to the ground. Recreational, photo and video models tend to have more moderate climb/descent speeds, while professional or racing drones can rise and fall much faster. This indicator can be used to evaluate how quickly the copter can rise to a height for filming or, if necessary, avoid obstacles, and a high descent rate will be useful if the drone needs to be returned to the ground quickly and safely.
Wind impedance
The ability of a quadcopter to maintain and maintain stable flight parameters in windy weather. In this column, it is customary to indicate the wind force in meters per second, which ensures trouble-free takeoff and landing of the drone within the permissible wind speed. Directly in flight, copters can overcome the resistance of even faster winds. But takeoffs and landings with wind strength above the designated level are fraught with unpredictable movements of the drone, loss of control and an increased risk of emergency situations.
Matrix size
The physical size of the photosensitive element of a camera. Measured diagonally, often indicated in fractions of an inch — for example, 1/3.2" or 1/2.3" (respectively, the second matrix will be larger than the first). Note that in such designations it is not the “ordinary” inch (2.54 cm) that is used, but the so-called "Vidiconovsky", which is less than a third and is about 17 mm. This is partly a tribute to the tradition that comes from television tubes — "vidicons" (the forerunners of modern matrices), partly — a marketing ploy that gives buyers the impression that the matrices are larger than they really are.
Anyway, for the same resolution (number of megapixels), a larger matrix means a larger size for each individual pixel; accordingly, on large matrices, more light enters each pixel, which means that such matrices have higher photosensitivity and lower noise levels, especially when shooting in low light conditions. On the other hand, increasing the diagonal of the sensor inevitably leads to an increase in its cost.
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.
Photo resolution
The maximum resolution of photos that the standard quadcopter camera can take. This parameter is directly related to the resolution of the matrix (see above): usually, the maximum resolution of a photo corresponds to the full resolution of the matrix. For example, for pictures of 4000x3000 pixels, a sensor of 4000 * 3000=12 megapixels is provided.
Theoretically, a higher resolution of photography allows you to achieve highly detailed photographs, with good visibility of fine details. However, as in the case of the overall resolution of the matrix, high resolution does not guarantee the same overall quality, and you should focus not only on this parameter, but also on the price category of the quadcopter and its camera.
Also note that the high resolution of the camera affects the volume of the materials being shot, for their storage and transmission, more voluminous drives and “thick” communication channels are required.
Full HD filming (1080p)
The maximum resolution and frame rate supported by the aircraft camera when shooting in
Full HD (1080p).
The traditional resolution of such a video is 1920x1080; this is what is most often used in drones, although occasionally there are more specific options — for example, 1280x1080. In general, this is far from the most advanced, but more than a decent high-definition video standard, such an image gives sufficient detail for most cases and looks good even on a large TV screen — 32 "and more. At the same time, achieve a high frame rate in Full HD It is relatively simple and takes up less space than higher resolution content, so Full HD shooting can be done even on aircraft that support more advanced video formats like 4K.
As for the actual frame rate, the higher it is, the smoother the video turns out, the less motion is blurred in the frame. On the other hand, the shooting speed directly affects the requirements for the power of the hardware and the volume of the finished files. 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 Full 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.