Camera-equipped unmanned aerial vehicles,also known as drones,have received a great amount of attentions over the past few decades.This gadget is applied to a variety of fields including but not limited to aerial surveying,building and monetizing YouTube channels,delivery service,environmental regulation and compliance,disaster relief,feature filmmaking,low altitude banner advertising,news footage,pipeline and electrical line inspection,precision agriculture,and real estate videos.Among them,aerial photography and cinematography used to be beyond the reach of ordinary people,but the advent of consumer drones makes it available to everyone.It is possible to purchase a ready-to-buy 4K video drone for just a few hundred Dollars or Euros,which can capture raw video footage for filmmaking or record adventures of travelers.As a result,the number of drone sales is burgeoning.“In the United States alone,the Federal Aviation Administration(FAA)predicts that more than one million drones will be sold over this holiday season;many more will be sold in other countries across the world.”（Spencer,2016）
Under this background,an analysis of drone services in shooting still images and recording videos was conducted in this paper on the basis of computer technology,aimed at providing reference and knowledge for targeted readers to learn more about drones before buying their first drone.
The flight of drones may operate under remote control or onboard computers,with a computer-intensive operating system that ensures collision avoidance,radar surveillance and precise landing.Problems such as battery failure,battery depletion and the exceeding of the remote-control range will trigger“return-to-home”,by which the drone will automatically fly back to the original position and land safely.To guarantee that there is enough electric power to propel a drone to return,a common means is to equip the drone with standby batteries.
Another advantage that every drone is trying to gain is long flight time.When the majority of flight times for current types of professional drones are between 10 and 25 minutes,the Walkera GPS QR X800 gets an amazing 40+minutes of flight time,allowing operators to take more photos or videos in one takeoff.However,the time is still too much shorter than the one a real photographer has.So,why is the drone still welcomed by them?Actually,there are a lot of natural scenes that are out of the reach of human traces but instead can be shot into images by unmanned aerial vehicles;even for accessible landscapes,the shooting angle is still limited more or less,in whose case the camera-mounted UAV of small size and flexible rotation can function better than individuals.What is more,the drone is supported by the first-person view technology,allowing for more precise flying around obstacles through remote control.Most of drones in the market have the function of obstacle avoidance.The Microsoft open-source AirSim allows developers to test and train their drones in a photorealistic environment,attempting to reflect the real-world navigation challenges in an authentic manner.Microsoft says the software is highly accurate because“its simulator takes advantage of recent advances in graphics processing technology to provide accurate virtual versions of real-world details like shadow,glare from the sun,haze and pooled surface water on roads”.(Darrell,2017)Therefore,drone images and videos are often taken at larger scopes and safer conditions.
With all the advantages of drone services in shooting images and recording videos,here comes a question:when offering the same creative edges,will drone images be used as common as drone videos?The answer is no,considering the higher demand for skills in mastering still photography than video.According to Alex Grymanis,“If you are shooting action–trying to focus,compose and capture remotely using an iPad–that can be really difficult while you are trying to fly the drone too…You need to think of the drone’s height and position relative to the subject,and how to time everything so you capture the right moment.That’s a lot to do–it’s much better to have one person flying the drone,and another shooting the pictures.”(2016)With state-of-the-art cameras and sensors big enough,these technical difficulties are possible to conquer.Nevertheless,it would be too costly for drones to carry mirrorless cameras than cheaper equipment,albeit riskless in capturing satisfied images;also,the size limitations of drones affects the size of sensors in them,producing plenty of noisy signals that will be noticed in taking still photos but are negligible in video shooting.Also,a larger sensor helps each pixel in occupying a larger sensor area,meaning the ability to capture more light,thus obtaining better dynamic range and better details.Therefore,in order to ensure the image quality,developers equip drones with more“eyes”in different directions(such as forward and downward dual vision sensors and the main camera),by balancing the requirements of large sensor area and good performance in obstacle avoidance.
In terms of computer control,some of the drones use WI-FI for video transmission and controls,which have their shooting area limited by the range of WI-FI signals.Other drones are built-in with GPS,extending its effective coverage with more aerial options.Both of these autopilot modes are better than any pilot can.This is particularly true in advert weather conditions.With much higher speed of calculation in monitoring and adjusting its locations,GPS-enabled drones are able to achieve flight accuracy.
All in all,with reachable angles that may otherwise be impossible,drones can be powerful aids for photography or videography.In the near future,with the further development of remote control and other computer technologies,drone devices may become smaller in size and better-behaved in performance,and the cost of getting an unmanned aerial vehicle is hoped to continue dropping.Apart from the majestic images and videos one will capture,there will be more emotional or personalized elements conveyed in the service of this amazing device.