Use this blur technique to add a spicy kick to sports and wildlife photography
By Bill Hatcher
Flip through any sports magazine and you'll find flash-blur photos. You know the look: an image of an athlete caught in mid-action, illuminated by a strobe and trailed by a colorful blur of motion.
The technique of flash-blur photography can produce some of the wildest and most experimental of flash images. Flash blur is achieved by combining the camera's slow shutter speed, which blurs the motion of your subject, with the action-stopping properties of the strobe, which freezes and sharpens the moving subject. Flash blur can be the perfect tool for punching up the action and light in drab low-light situations.
Many outdoor photographers stay away from using flash blur because of its apparent unpredictable results, but with a little practice, you can tame the wild side of flash blur. The mastery of flash blur will add to your quiver of stunning lighting effects and can be accomplished with a simple on-camera flash.
Technique Don't be intimidated by the technique of flash-blur photos, since it isn't dependent on expertise with a flash. Instead, it's your ability to recognize when the ambient-light situations are right to use this technique. When the idea blinks in my head that it's time to use flash blur, the location is invariably under a dark canopy of trees, just before the sun has just touched the horizon, or when I see the potential of mixing unusual light like that of a large bonfire with a twilight dance ceremony.
The best time to shoot flash blur is in low light (sunset, sunrise, near the light of a campfire, under street lights, etc.), when setting slow shutter speeds for your blur and finding a dark shadowed background for your subject is no problem. For the flash-blur scenario, your moving subject is front-lit or sidelit by the existing ambient light. This wash of ambient light on your subject is the light that produces the blur ghosting in your photo. A darkened background helps pop your flashed subject from the background scene. Potential backgrounds are a twilight sky or a stand of trees.
The flash settings are simple. Set the flash for rear-curtain sync (this function is found in your camera's flash settings); this makes your flash fire at the end of the long shutter exposure. The rear-curtain sync effect makes the blur appear naturally behind the subject's direction of movement. Next, set your flash for its normal, full-power TTL or auto setting. Your flash is now ready for flash-blur action.
For a flash blur, the most important camera setting is shutter speed. In my metering, I underexpose the ambient light by one stop. When shooting a flash blur, the strobe is always the primary light illuminating the moving subject. The shutter speed I use depends on how long of a blur I want and how fast the subject is moving. This is one place where reviewing your photos on a digital camera's LCD is a real asset. For fast action such as biking or skiing, I start shooting with my shutter speed at 1/40 sec. For a slow-moving subject, I typically shoot around 1/15 sec. To create more blur across the frame, I may slow my shutter even more, to as long as 1/2 sec. After shooting a few shots, I review my digital results to check my composition, focus and the quality of the blurring.
There are two techniques for handling your camera to create flash blurs. Each produces its own look. The first method is achieved holding your camera steady and taking the shot as the action moves in front of the camera, as you might photograph a skier jumping. The second option, and the one that I find produces the coolest results, is to follow the action with the camera, shooting as you pan with the moving subject. By moving the camera, the background blurs and the flash freezes the subject action in an abstract wash of blurred streaks.
A few cautions as you experiment with flash blur. Avoid any bright lights or areas behind the subject since this shows through your subject's ghost blur. If your subject is too close to a background, the flash may illuminate the background. The solution to this problem is to move farther from the background, or use your flash off-camera with either a TTL cord or wireless setup, allowing you the freedom to redirect the flash so it doesn't illuminate the background. Lastly, be prepared to shoot many frames to get the perfect shot.
Essential Gear... Bill Hatcher uses Nikon's SB-800 AF Speedlight to capture his flash-blur images. Pair it with the Quick Recycle Battery Pack SD-800 for fast recycle times of about 2.7 seconds and get an edge on the action. The flash head rotates and swivels, letting you put the light right where you need it for creative impact. Estimated Street Price: $315. Contact: Nikon, (800) NIKON-US, www.nikonusa.com.
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