I took several hundred photos in daylight as an experiment. Some conclusions that likely translate even to night photography are:
- Avoid direct front or overhead lighting. It's too harsh. Prefer sidelit or backlit images, but with the primary lights sufficiently high that there aren't distracting reflections.
(Canon EOS 550: f5, 1/500 sec, ISO 200, 200 mm, detail)
- Spot-meter the exposure on faces and bodies. Most of the surrounding water will likely be exposed just fine.
(f/6.3, 1/320 second, 127 mm, ISO 200, minimal cropping)
- You don't need super fast shutter speeds. When you think about it, you realize a spash doesn't usually move very fast: a few meters per second and often much slower (for waves and currents). The splashes are sharp and clear on the original of the previous image; here's a detail:
A little motion--about 1mm in this scene--is good; the water looks more natural than when it's completely frozen.
- A moderate telephoto (135-300 mm full-frame equivalent) is a good idea for keeping you away from the water. It will provide nice framing for close shots but can zoom out enough to include groups of people in the middle or across the pool.