Tips for winter aerial photography of drones

It is extremely harmful to frozen planes and drones. The icing of the blades will increase the weight of the aircraft, which is not conducive to the normal flight of the drone. When flying unmanned aerial vehicles over the water, special attention should be paid to prevent icing, because the steam fog generated when cold air flows through warm water with high temperature can easily condense into ice.

2, heat preservation

Flying unmanned in cold winter makes people tremble, because you stand still most of the time, so it will be a little colder than other winter activities. Pay attention to wearing warm clothes, especially warm gloves, to ensure that your fingers can flexibly control the drone. Since you want to operate a mobile phone or tablet, you'd better choose touch-screen gloves, half-finger gloves or remote control gloves. Personally, I prefer to operate the drone in the car, but if you want to do the same, according to the regulations of the Federal Aviation Administration (FAA), you must ensure that the drone flies in the field of vision.

3. Battery performance

In a low temperature environment, the battery life of the drone will be reduced. You'd better make double preparations, not only to plan the flight route, but also to keep the battery warm. Try to keep the battery warm all the time. I usually put the spare battery in the car unless I want to take an aerial photo far away from the car. If I don't put it in the car, I will put a warm handbag in my backpack (to avoid direct contact with the battery). You can also put the battery in your coat pocket to keep warm.

When you are ready, start the drone and hover in the air for about a minute to warm up. When the temperature is lower than 15, most DJI people don't have a chance to give a low-pressure alarm. If you receive an alarm prompt before takeoff (to be on the safe side, please check the battery temperature before takeoff), you can try to pull out the battery for preheating. Because cold conditions will lead to voltage drop, so don't fly at high speed for a long time. In short, avoid violent flight, control flight time and land as soon as possible in cold environment.

4. Humidity

Rain, fog and snow: the air humidity is high in winter, which is very harmful to the motor and sensitive parts of UAV. And you should also avoid getting wet by the camera lens, mobile phone or tablet screen. Avoid flying in foggy days (because of low visibility). Although some people have succeeded in flying in snowy days, I don't recommend flying in this weather. If it rains, it must be grounded immediately. Pay attention to protect the screen of your mobile phone or tablet. If it is snowy, I usually use the protective cover of the remote control and tilt the remote control slightly to protect the screen of the mobile phone. Finally, choose the landing site, because when the plane is about to land, the propeller will set off a large snow fog.

5. Visibility

Fog (especially over the waters in early winter) and low clouds are common in winter, and usually appear within 400 feet (about120m). In addition to the risk of increased humidity, cloudy weather will also reduce visibility, so we must take precautions. This kind of weather can bring special artistic effects to your aerial photography, but you need to fly carefully.

6. Air

Nevertheless, aerial photography in winter is not without advantages. With the decrease of convective heat transfer in winter, the airflow is more stable, which is conducive to taking smoother and more stable photos and prolonging the exposure time. In sunny summer, I can only expose 1/2 seconds or 1 second at most. I can extend the exposure time to 8 seconds in winter, and the photos taken are very good.

7. Density height

Another function of cold air is to make your drone fly at a lower density. Simply put, the density of cold air is higher than that of hot air, and it will shrink and sink after being piled up in large quantities, which means that the drone needs to exert force on more air media to move forward. According to Newton's third law, this will give the plane more thrust. Although this effect has no obvious influence on flight speed, it can improve flight performance to some extent. My Phantom 4 has a top speed of 22 miles per hour in summer and once reached 24 miles in winter.

8. Exposure and white balance

First of all, remember to take photos in RAW format. If shooting is not in full manual mode, the camera's metering system will think that the scene light is bright and it is easy to be underexposed, so it is necessary to increase the exposure compensation appropriately, about 1. In addition, you will find that the white background taken by the camera in automatic white balance mode will be blue, so remember to adjust the white balance.

9. Post-processing

Post-processing is a process in which different people have different opinions, but you need to remember some precautions for photo processing of winter scenes. Because the white snow scene is reflective and usually takes up most of the picture, you need to find a way to solve the problem of insufficient details. I usually turn up the brightness and contrast of the camera, and it will be slightly higher than usual when taking landscape photos. This will highlight the unique sense of detail and layering of the snow scene. In addition, the foggy scene will make your aerial photos look better.

This is an attempt, but by slightly improving the brightness and contrast of the camera, you can take this kind of ice and snow picture. Avoid excessive adjustment of brightness and contrast.

10. Wonderful winter

The aerial photography of winter scenery is like a fairyland on earth, and the aerial photography of summer scenery is closer to reality. The abstract images of aerial photography in winter deeply attracted me. You can be creative, find a unique angle and take different styles of aerial photos.

Finally, play it by ear. Flying drones in winter needs extra care, so remember to read the user manual carefully and take adequate precautions to ensure safe flight. Have a nice flight!