Maintaining a high speed – Shutter Speed #6
The day was cloudy, cold and windy. My spirits suffered under the poor conditions and I knew shooting track, even middle school age kids, was going to be difficult.
I’d already decided to shoot at f4, the widest opening on my Nikon 300mm lens. I wanted to maintain emphasis on the runners without a distracting background. I knew that would make focus more critical, especially when using single-point focusing. There would be not time during focus tracking to adjust the focus point in the viewfinder.
I settled on top center focus for horizontal images and near top center for vertical shots.
Knowing that I’d need a fast shutter speed to stop the action and that I was staying with f4, I chose to use aperture priority auto exposure with exposure compensation depending upon the subjects.
The clouds weren’t consistently the same density so exposure would changed as thicker clouds with sprinkles of rain passed over the field. Thinner clouds brought just a little more light, sometimes in the middle of a race. I could have shot manual exposure setting both f-stop and shutter speed but the varying light levels would have made it more difficult to adjust during a race. Letting the camera determine the shutter speed was my best plan.
That meant that I’d have to increase my ISO higher than normal to at least ISO 800. Most newer digital cameras have much less noise at the higher ISO settings. I could have easily increase the ISO past 1600 without any significant increase in noise. The light was flat enough that the shadows didn’t get too noisy and the highlights weren’t blown out.
Shooting at a shutter speed of 1/1000th or higher will stop most track action depending upon the runner’s movement in relationship the the shutter plane. Running at me, this runner and his two followers were easily stopped with 1/1250th setting.
Auto-focus followed him nearly perfect as he hit the finish line. The narrow depth of field from the f4 setting kept him in the place of focus and blurred the trailing runners enough to remove them as sharp distractions.
My settings, both shutter speed and f-stop, might have been different if I’d been shooting on a normal sunlit day.
My ISO would have been lower. It was raised to 800 because it was cloudy and I needed a high shutter speed.
The f-stop might have been f5.6 to allow a greater plane of focus on the main subject.
The shutter speed, being the most significant of my setting choices, would have remained at or greater than 1/1000th. Stopping the action was the greatest objective for this photo. All the other choices were determined by the shutter speed.
