DSLRs with video are here to stay. While it has crossed my mind that certain witnessed sequences would make a great movie, the ultimate capture for me is the decisive moment of an animal in action on a single frame. Although the focus of this article is animals in action, the same technical principles can be applied to any subject that moves. It could be your kid’s soccer game, cars whizzing past or air show acrobatics. The subject is not the key—how you go about capturing it is. Moving subjects are harder to capture than stationary ones, but adhering to a few tips will give you a higher return on your time in the field.
SHUTTER SPEED: The shutter speed is the key factor that determines whether or not the action is stopped. Commensurate with choosing the speed is the amount of light falling on the subject. The more light, the faster the shutter speed that can be utilized. While there are many schools of thought as to whether shutter priority is the best mode to use, the key is to be aware of the speed at which the camera fires relative to the speed of the animal. Great results can be attained if you use aperture priority. Spin the aperture to its widest opening to obtain the fastest possible shutter speed. Shutter priority can be used, but be cognizant of the aperture the camera chooses. Manual also works well, but you have to set both the shutter and aperture to get the proper exposure. The faster the action, the higher the necessary shutter speed. The more you photograph the same subject, the sooner you’ll learn what shutter speeds are required to stop motion. If you’re just starting out, I suggest you try to use the fastest speed possible and work down from that point. It’s better to “Over Freeze” a subject than to start with one that blurs due to too slow a shutter.
DIRECTION OF THE ACTION: Logically, the faster the action the faster the necessary shutter speed to arrest it. For instance, a frame-filling image of a diving hawk requires a faster speed to freeze than a full-frame horse trotting through a field. But equally as important to take into consideration is the direction of the movement. The same animal that approaches the camera doesn’t need as fast a shutter to halt the action as if it crossed perpendicular to it. The beauty of digital capture is you can take a test shot to see if any blur is a result of too slow a speed.
ISO SETTING: If the ambient light is bright, higher shutter speeds can be utilized. High thin clouds introduce a level of difficulty if very high shutter speeds are necessary. Thick gray overcast conditions severely limit the options. Thankfully, digital photography allows us to bump up the ISO sensitivity to obtain faster shutter speeds. The problem of the law of diminishing returns comes into play if it’s too dark, necessitating the use of too high an ISO. As the ISO is increased, so is the amplification of digital noise, which degrades the image. As the technology of sensors continues to improve, it has allowed shooters of high-end cameras to maintain great quality even at ISOs of 3200, but the price tag on these cameras is high. Post processing noise reduction also helps.
AUTOFOCUS TECHNIQUES: To increase the chance of getting a sharp photograph, set the camera to Continuous Autofocus. This allows the shutter to be released even if the subject is not in focus. Even though frame numbers one and two may have a soft rendering, the hope is that as you continue to fire off a burst, the lens catches up with the action so the rest of the frames in the sequence are sharp. Simply delete the images that are out of focus. If you use Single Focus Priority, the shutter won’t fire unless the camera confirms the subject is in focus. This prevents the possibility of having the lens catch up with the action. Based on the placement of the subject in the frame, be sure to highlight a focus point that overlaps it. If the sensor isn’t placed over the animal, the lens will focus in the wrong location.
The Basics — There are a number of factors that determine how well action can be arrested.
a) Know the Species you Intend to Photograph: Do some research on the animal you intend to photograph to learn its behavior patterns. What signals does it give that it’s ready to fly? What does it do before it jumps? What time of the year is it most active—think mating season. What does it prey upon? The more you know and the more time you spend with a certain animal, the better your chance of capturing the peak moment.
b) Anticipate: Once you become familiar with the species, when it gives you a signal, be ready. Patience is most certainly a virtue. Many wildlife photographers stand around waiting for hours to capture 60 seconds worth of activity. But when it happens, those 60 seconds are very rewarding.
c) Be Prepared: Bring lots of memory cards and spare batteries. During the waiting period for the animal to do something, photographers often pass the time admiring their work on the LCD of their camera. This eats up battery power. The last thing you’d want to experience after a long wait is a dead battery, so be aware of its capacity and change it if necessary. Additionally, you may need to follow the animal once it moves, and unless you have the batteries and cards with you, all the following will be futile if you run out of either.