Tracking Bicyclists
I took a walk through Central Park in the evening and watched the bicyclists zoom through the stream of pedestrians converging on the Delacorte Theater.
These shots are with the D70 set to Auto-Focus Continuous. The focus tracking was actually pretty impressive, keeping the subject in focus from at least sixty feet out to maybe ten feet away, all along the curve of the road, while they closed in at 20 or 30 miles an hour. The lens was open to f/8, and the overcast evening light required a shutter speed of 1/10, perfect for the motion blur. This was all an experiment inspired by this DPReview.com posting on the bike race in Lower Manhattan this past Saturday.
I’m now impressed: the continuous focusing was something impossible on my old FM10 — at best, I could pick a pre-focused spot and shoot, but then I’d only have motion blur on the cyclist rather than the background. Even with the D70, the vast majority of shots didn’t come out. With this sort of tracking, I have to remeber to follow through, rather than stop pivoting when I press the shutter release. Using a rear-curtain flash might have also helped, though I’m not sure I would have wanted to distract the riders by shining a bright light in their eyes.
It was interesting standing there for the ten or so minutes I spent shooting. The cyclists do a lot of yelling at the pedestrians, who have a habit of wandering onto the road while talking on their cell phones or chatting in the middle lane, oblivious to everything going on around them. There was one near accident, where the cyclist had to swerve drastically not to run someone down. In any case, everyone should wear helmets.
Update: I just realized this cool thing. In some of the pictures, I have park lamps in the background. I was wondering why these lamps weren’t smeared across the picture smoothly. A quirk of the CCD, recording the image in pulses? No, it’s the lamps that are pulsing. You can even figure out the hertz by multiplying the flickers with the shutter speed (around 120 hertz for most of them). Neat.