Dawn of the Drone: An Aerial Video and Photo Primer

Drones and POV Cameras

In today’s diversified market, drones are available to just about anyone who can imagine using them for just about any task. Like it or not, we live in a “GoPro is good enough” society that coexists with the less populous world of professional filmmaking when it comes to aerial video. And using professional gear with drones creates additional challenges. Weight is to a drone as Kryptonite is to Superman. With increased weight comes a degradation of performance in many areas of drone operation.

Heavy-lifting: the Movi 5 and Panasonic GH4 on the Cinestar 8HL

It’s no surprise, then, that we see so many small drones designed around relatively small POV camera bodies. If your production needs require a larger-format camera such as a DSLR or a RED, then the available options narrow considerably, and require an even greater understanding of technology and pilot proficiency. With the goal of professional operation with professional gear in mind, let’s start our journey into the world of aerial cinema by discussing some of the technology, followed by a look at the latest regulatory posturing that will impact our craft moving forward.

Key Elements of Drone Technology

The power source for modern-day drones and all of their on-board electrical clients is the Lithium Polymer (LiPo) battery. This game-changing battery technology is largely responsible for the proliferation of the multi-rotor drone, due to the LiPo’s ability to release large amounts of power over very short periods of time. While similar in some respects to the Lithium-ion batteries we use in our cameras, the LiPo is comprised of a much more unstable chemistry and requires greater attention and care to avoid permanent damage and catastrophic destruction through uncontrolled fire. I’ll discuss LiPo batteries in more detail a bit later in the article.

A multi-rotor drone is equipped with a number of electronic components mounted to an airframe, all working in concert with one another to allow the pilot to issue commands from a control unit (a radio transmitter of sorts) that will effect change in altitude and direction as desired. At the heart of the system is a flight control unit with a very sophisticated set of electronic circuitry and sensors. Gyros sense altitude, accelerometers sense change in direction and barometric sensors detect changes in altitude. Essentially, your multi-rotor drone is a flying laptop making thousands of calculations milliseconds of time to ensure that your aircraft is stable in flight.

The Futaba transmitter

Each drone also has a number of brushless electric motors, typically one for each boom. On each motor is a propeller. While the propellers are identical in size and pitch, half of them are designed to rotate clockwise, the other half counter-clockwise. These propellers are nothing more than small wings that develop lift as they rotate. The faster they rotate, the more lift they generate. When the rotational rate of the propellers is changed over time, the resulting torque and speed differences in the motors cause the aircraft to yaw (what we call “pan” in video/filmmaking) left or right, move forward or backwards and bank left or right (both dolly moves in cinema). Each motor, however, is useless without a motor controller or electronic speed control (ESC). Electronic signals from the flight controller to the individual ESCs regulate the amount of power sent to each motor, thus changing the rotation speed of the propeller.

So there you have the basic configuration of a multi-rotor drone. The pilot issues commands to climb, descend, fly left or right, forward or back and to yaw (pan) left or right. The flight controller makes it happen with the help of the ESCs, motors, and propellers.

Just as a boat launching into a river is subject to the river’s current, your drone taking off into the air is subject to wind—your drone will move in the direction the wind is blowing until you command otherwise. Learning to fly and developing your muscle memory with a drone will serve you well as you begin to leverage some of the more advanced features of the typical drone being used in the video world. Two such features are the global positioning system (GPS) and the electronic compass. Together, these two components provide specific position and heading information.

A typical flight control system, the DJI A2 with GPS and iOSD

The flight controller processes this information and provides position- and altitude-hold functionality that relieves the pilot of the need to “fly” the drone. This advanced flight control feature keeps the drone at its desired position and altitude even when the wind is trying to blow it away, and is the single reason that users with no drone experience can purchase multi-rotor units off the shelf and fly them with some success.

Without this automation, the flight experience requires a higher level of proficiency to maintain positive control of the drone. If you disciplined yourself by using only the basic setup when learning to fly, you can rest assured that when the GPS/compass systems fail (which they will, from time to time), you’ll have the necessary skill set and pilot proficiency to recover from that failure.