By combining off camera flash with slow shutter speed and Slow/Rear Sync on your camera, you can create some interesting motion effects in your photography.
Since the flash fires at a duration of well over 1/1000 sec, it will freeze part of the shot while other elements in the image appear to be in motion. Sometimes the light form the flash gives you surreal ghost effects on your subjects.
This is even more pronounced when you apply a panning technique. One thing that I often do is use front-to-back panning instead of just panning from side to side, which is the usual way that we’re taught how to pan.
This works especially well when shooting subjects that are moving towards or away from you. I do this by following the subject or tracking backwards with my body as I’m getting ready to press the shutter.
Here are a few shots that illustrate some of the things you can do with motion photography and flash.
In the first shot, I’m panning front to back with an 85mm lens, shooting at 1/60. Light is a single SB-800 about thirty feet off to the left, 90 degrees off axis from the camera. In the second example, I’m doing a similar technique, but this time with a shutter speed of 1/60 sec using a 14mm lens. The panning and on camera flash help to freeze part of the subject in an environment of movement in both shots.
In this first cyclocross image, I’m using a shutter speed of 1/50 sec, with a 24mm lens. When the subject races by me, I’m pivoting forward with my body as I press the shutter speed. The light is coming from two SB-800’s, set at 105mm with dome diffusers on about fifteen feet away about 80 degrees off axis from the camera. The flash makes up for the overall darkness of the forest. You can see my setup and, as well as the scene without flash in the next shot.
This one was shot at 1/30 sec with a 100mm lens. The lights were two bare SB-800’s on a Nano Stand about thirty feet away from the subject, this time coming in from the right. The slow shutter speed communicates the feeling of fast motion, while the pop of light from the flash gives me a ghostly sharp subject, which helps to anchor the image down.
In this shot, I also underexposed the ambient light by two stops and made up for that on the TTL. As with the other cyclocross image, both flashes were triggered with the D700’s pop up flash. In all of these images, I'm using manual exposure on the camera and TTL on the flash, with compensations of 0 to around -1 stop on the flash.
Dan Bailey is a pro adventure and outdoor photographer based in Anchorage Alaska. This post in a excerpt adapted from his new 83-page eBook on off camera flash for outdoor photographers called Going Fast With Light. In it, he explores simple, strobist-style lighting techniques and gear that won't slow you down. Visit his blog at www.danbaileyphoto.com/blog