It's ironic that I am so preoccupied with photographing motion, essentially capturing the essence of speed and dynamics in what is by its definition a static medium. Perhaps it is because, as a kid, I was fascinated by stroboscopic photos that seemed to reveal slices of time that humans never otherwise see.
In any event, you don't need access to a bank of strobes or Matrix-like super high-speed photo gear to do this sort of thing yourself. Take this photo that's getting a lot of views on Flickr right now, for example. The photographer captured a water balloon milliseconds after it was popped over the model's head.
My daughter and I decided to perform our own version of the "water hat" experiment. Since it's not very warm here in the Pacific Northwest (we live in Washington state), we skipped the "hat" part--Marin popped the balloons off to her side, so she'd stay as dry as possible.
We started by filling some balloons with water. I filled; she tied them off; and we took a brownie pan of six out in to the front yard in the early afternoon, when we'd have the most light.
Light is important because you'll want to use the absolute fastest shutter speed possible--and the more light you have, the faster you can set the shutter. Pick a sunny day, and, if your camera has an aperture priority mode, dial in the maximum aperture (like f/2.8 or f/4). With the aperture open all the way, the camera will counter with a fast shutter speed. I shot my photos at between 1/2000 and 1/8000 second, but you should be able to get interesting results as slow as 1/1000 second. If you have trouble getting a fast shutter speed, increase your camera's ISO.
Having a fast shutter speed is great, but how do you know when to shoot? Without fancy sensors or access to a science lab, it takes a little planning and luck. I set my camera on a tripod and framed Marin, poised with the water balloon.
One last detail: Set your camera on its fastest shooting mode. If you have a bust mode that takes a slew of pictures when you press the shutter release, you've finally found a good use for that setting. If you have a "motor drive" setting that takes pictures continuously as long as you hold down the shutter release, choose that.
Now it's time to rehearse. I told Marin I would count off "3, 2, 1, poke!" Like the banter between Danny Glover and Mel Gibson in Lethal Weapon, she asked if she should pop the balloon on "poke," or wait until after the "3, 2, 1, poke," and then pop it. (I verified that she should pop it on "poke.")
Taking the photos
I counted down. "3, 2, 1..." and just as I said "poke," I pressed and held the shutter release until a half dozen photos had been taken. Above is the first successful photo I got.
We couldn't have asked for a better result out of the starting gate: We'd captured, almost perfectly, the instant after the balloon burst, but before gravity had a chance to make the water lose its form. In essence, Marin was caught holding a ball of water.
What if you miss the magic ball-of-water moment and get a shot of water dribbling between your model's fingers? That's why we brought a brownie pan full of balloons. Just try again, and possibly vary your timing. You can start your photo burst before the "poke" signal, or try to make it happen simultaneously. Either way, given a few balloons, you're bound to get some astonishing photos.
Your results will depend upon your camera's fastest shutter speed and how many photos per second it's capable of capturing, as well as other less tangible factors like the available light and the way you compose and execute the shot. You can see more photos from this experiment on my Flickr page.