Using a UAV to map a field, city block or place of upcoming construction will require certain skills and knowledge from you. Even if some theoretical points are obvious, then the practice will be a real test for a beginner.
In some countries, to use the drone, it must be registered, and its pilot must have a special certificate.
Experience has shown that an SD card may simply fail or be lost. Therefore, take a spare before traveling to the place of shooting. It is good to have several spare (charged) batteries, propellers, and to avoid the need for other elements, pay more attention to training. Collision of the propeller with the soil during take-off/landing is quite possible. All propellers (installed and spare) must be well balanced, otherwise during the shooting you run the risk of getting the Jello effect - a kind of ripple.
The flight of a large drone is also a danger to people - it is not for nothing that they are compared with flying lawn mowers. In case of engine damage, the propeller may fly off to someone's face. Therefore, the flight path must be known in advance, the drone operator must have a clear plan in case of emergency. The most common situations of this kind are battery drain, remote control loss or UAV collision with something.
To make a beautiful video «camera flight through the picture», you need to know exactly the position of all trees and other high-altitude objects. Otherwise, your shooting will be interrupted by an accident and repair. Not only that, you need to practice well, to learn how the drone behaves in this configuration. If you add another battery, this will increase the flight time, but does not compensate for poor piloting skills and icncrease the flight weight.
To make a review video or several panoramic photos, a simple drone is enough. If you are planning studio-quality shooting, you will need a good camera with a complex suspension, so the requirements for carrying capacity are increasing. In fact, the type of drone depends on which camera you want to use. DJ quadcopters are favorably modular. You can independently choose a complete set before each departure, changing the number of installed batteries, cameras, additional devices. Of course, you or the pilot should have experience managing your drone with different levels of workload.
To obtain a cartogram with the NDVI index of plants, you will need a special camera and software. To determine the height of plants or to create a 3D model of a quarter, a special flyby mode with an inclined camera (3D Mode) will be required when the drone photographs each element from two sides. The area of the site and expected flight distance must be compared with the capabilities of existing batteries.
To get a high-quality images from the camera, you need a good suspension. Three-axis suspensions provide stability in three directions (yaw, pitch, roll), two-axis suspensions only in two directions: pitch and roll. 3-axis suspensions for a quadrocopter video camera are heavier, 2-axis suspensions are lighter. When purchasing a suspension, make sure that it has the appropriate mounts for your type of quadrocopter and for fixing the camera.
Sidelap — overlapping of the images between the rows of the span and Frontlap — overlapping the previous and subsequent frames. The higher the resolution of each frame and the overlap of the survey, the better the processing when creating a cartogram, but the stronger the memory of the SD card is used. To obtain a cartogram of the NDVI field index, images overlap of about 70% is necessary.
A cloudy day is well for shooting because there is diffuse lighting. Or choose a time from 10-00 to 14-00, when the sun is high above the horizon. However, it may be difficult to analyze the sequence of such images (crop ripening taken with a different level of illumination each time), therefore, the Sequoia+ camera allows you to create images with calibrated brightness values under changing ground lighting.
The quadcopter has at least two flight modes - for beginners, where all the commands from the remote control are perceived weaker and normal. Each has its own characteristics. For example, in the beginner mode, even when you see an obstacle, you may not have time to fly around it. In normal mode, one touch of the control lever can throw the drone into bushes that were not so close.
If there is an automatic mode, it can also unpleasantly surprise. The quadcopter will constantly intervene in the control process, which will make the trajectory not entirely predictable. Therefore, experienced operators, to make a video, uses only manual control.
A spectacular video, when the camera first approaches the face, and then moves up, surveying the whole city, requires some experience. Even professionals need to do a few takes for this. And again, you need to know thoroughly the location of the electrical wires, trees, and other high-rise objects.
If your idea is complicated in execution, then you can buy DJI Inspire 1 Pro with two transmitters. Thanks to which one operator controls the flight, and the second - the camera itself. In this case, the movie shooting process should be performed by a well-coordinated crew consisting of a drone pilot and a camera operator.
If the drone operator uses the first-person view mode, you always need another person who monitors the flight from the side, especially during takeoff and landing.
AeroVirnment proposed a radical approach to solving the piloting problem by developing the Quantix UAV. Its feature is the complete lack of manual control. In order for it to «fly» you indicate to him the field for monitoring and press the start button on the remote control. After which take-off, inspection and landing are carried out automatically.
