Better Drone Photos Through Manual Camera Settings
By Nathanael Showalter, September 5, 2017
On a professional scale, integrated drone cameras are still performing at the low end. This is the result of several factors, including keeping costs within a range that is still attractive to consumers while providing a usable product, but probably the most significant factors are size and weight. The mechanisms and parts that lend themselves to high-quality, high-performance digital photography are simply too large, complicated, and/or heavy to be integrated into a small airframe and remote-controlled with a precision equaled by what the human hand and eye can do on the ground.
But almost every drone camera comes with a handful of manual settings, and understanding how to adjust these settings can make a big difference in what your final product looks like. These manual settings are usually at least two of the following: Shutter, ISO, aperture, and white balance. For the following examples, I used a DJI Phantom 4 Pro.
The shutter speed is a measure of how long the shutter of your camera stays open to allow light to strike the sensor, usually measured in fractions of a second. The longer the shutter is open, the more light strikes the sensor. If you are shooting on a bright day, the shutter will need to move faster, and open for less time to take a picture. If it’s dark, your shutter might need to stay open longer, maybe even for more than a second if it’s night time.
Shutter speed also defines sharpness of moving objects. If the light reflected off a moving object strikes more than one place on the sensor, you get motion blur. Sometimes you want motion blur, like when photographing a plane with a spinning propeller, and sometimes you want a crisp, clear image of something in motion, like an athlete performing a move. If the drone is moving, shutter speed will also affect blur; things that are farther away from the drone will appear sharp, while things that are closer will have more motion blur with a slower shutter.
ISO stands for International Standards Organization, but it defines the sensitivity of your camera’s digital sensor to the light coming in. ISO is helpful when you need a faster shutter speed or smaller aperture in low-light situations, but has to be used with caution because the higher a camera’s ISO, the more digital noise (“grain”) appears in the picture.
Drone cameras especially, since they usually have small, inexpensive sensors, are prone to digital noise when the ISO is turned up. This means that drone cameras are not the best for capturing sharp photos of moving things in low-light situations without a lot of grain and discoloration. It’s especially noticeable in solid-color surfaces, like a wall or the night sky.
ISO is measured in numbers from (usually) 100 to whatever the camera’s highest setting is. The standard ISO setting in good light is 100. At this setting, most drone photographers can expect a picture free of grain unless noise is brought out by artificially lightening the photo in editing. I personally find that setting my ISO anywhere at or above 400 begins to deteriorate my quality, so I rarely raise it over 1oo. Experienced photographers used to cameras with much better low-light performance (like the Sony A7Sii) may be frustrated by the limitations of integrated drone-camera ISO.
All cameras have an aperture, but very few drone cameras have an aperture that you can change, since aperture systems usually require extra moving parts. A handful of prosumer drones have them, including the DJI Phantom 4 Pro and any drone carrying the Zenmuse X5, X4S, or X5S gimbal systems. However, the Zenmuse X3, the Phantom 3 Pro, and the Phantom 4 do not have a means of changing their aperture, and their aperture setting is fixed at around f/2.8.
The aperture is the hole that allows light into the sensor when the shutter clicks, and it serves two purposes: First, it is another way to control how much light gets to the sensor when the shutter is triggered; and second, it controls how much of the picture is in focus.
Drones are not often required to photograph things that are close by, and as a result, there is not much call for adjusting the aperture to control focus. Shots that are intended to put one thing in focus, and everything else in the foreground and background out of focus, are taken with a very low aperture setting, usually around f/1.6 or f/2.8. Pictures that need everything in focus in the foreground, midground, and background are usually taken with a very high aperture setting, f/11 or f/13, if not more. The number after the f/ corresponds to how closed the aperture is; that is, f/2.8 is only closed a little, and f/11 is closed nearer to a pinhole.
The small aperture affects the way light enters the lens and sharpens the subject, changing the focal depth. A shallow focal depth is great for macros and portraits, and for adding depth and dimension to a shot. A deep focal depth – with a higher aperture – is great for keeping everything in focus, but also results in a flatter, more 2D look to the picture.
A camera’s white balance determines what colors read as neutral, without any red, green, or blue color values in them (so white, gray, and black, usually). The scale for adjusting white balance usually goes from Cool to Warm and is measured on a Kelvins scale. The Phantom 4 Pro uses a scale from 2000k (very cool) to 10,000k (very warm), and I usually end up shooting somewhere between 4500 and 7500, with a few exceptions.
Most digital cameras come with a series of automatic white balance settings to take your mind off the process, but there are times when an automatic white balance, or AWB, can take away from the desired effect. A good example is when trying to capture unique atmospheric lighting like Golden Hour, when the sun’s light is lower in the sky, less intense, and makes things a warm, golden color that looks amazing on landscapes and human skin. A camera using AWB may detect the yellow light and automatically correct for it, so that your landscape photo has some beautiful shadows, but lacks the coloration you wanted.
Also, if you are shooting an event that takes place over a period wherein the ambient light color changes (such as stage lighting or clouds passing over the sun), using AWB may give you a series of photos with different temperatures. This can ruin a time-lapse shot, for example.
The combination of settings you’re using on your drone camera gives you what’s called an Exposure Value (EV) on a scale where 0 best represents what the camera calculates is equal to the actual ambient light. You can use the EV to get an idea of how your settings might need to change. For example, if you are shooting with a shutter speed of 1/60, an ISO of 100, and an aperture of f/2.8 and your EV is reading as +2.0, you know that you probably need to speed up your shutter or close your aperture until the EV reads 0.0. If you’re using the same settings but getting an EV of -1.3, you may need to raise your ISO or slow down your shutter even more to get the EV closer to 0.
Some people prefer to shoot with a higher or lower default EV. I personally prefer shooting with an EV around -0.7 on the Phantom 4 Pro because it’s easier to lighten the P4P’s images than it is to draw detail out of overexposed areas. On the other hand, if you want a bright, dreamy effect, you can work to keep your EV around +0.3. This is popular with wedding photography.
In general, drone photography alone does not require the use of filters except when trying to achieve a particular effect. Certainly, for real estate or landscape photography, a drone’s shutter speed is usually sufficient to control exposure.
However, there are times when a photographer might want to slow down their shutter, like when photographing a river to get that ghost-like effect; or to get motion blur, or even to hold the shutter open during a long exposure at night so that people or cars moving past the lens will appear as blurs, leaving the still buildings and roads solid.
Filters act like sunglasses, reducing the light coming to the sensor to reduce the overall EV. Filters allow you to use a slower shutter and a smaller aperture value. Some also come with polarizing lenses, which cut down glare and make it easier to shoot details through water or glass.
Everything I’ve written so far is about still photography. The same principles apply generally to filming, but in digital videography the relationship between framerate and shutter speed adds another permutation to the mix. But the topic of video settings is likely to be a whole separate blog post.
One other thing: If your drone camera has an option to shoot in RAW or DNG format, I recommend using it. Those file formats store much more information in the picture’s poorly-lit and overexposed areas and make it easier to keep those details with careful editing. Shooting in a compressed format like JPEG will get you a more finished-looking product right out of the camera, but your options for editing with JPEGs are more limited. The raw formats usually need to be edited in a program like Adobe Lightroom or Photoshop.
So, while size and weight have put an upper limit on the quality of photograph an integrated drone camera can produce, the technology is changing to improve things like dynamic range, ISO noise, and resolution. In a few years, airborne cameras are likely to be more competitive to popular handheld professional units.