Shooting waterfalls, seascapes and long exposures safely

TUREFF• •0

Long exposures turn moving water into silk, flatten choppy seas into mist and stretch clouds into streaks. The technique is straightforward, but the places it is used most, slippery riversides and wave-washed rocks, are where photographers get hurt. Start with safety, then the settings.

Safety comes before the shot

Check tide times before shooting on any coast, and know whether the tide is rising or falling. A rising tide can cut off a beach or a rock ledge quickly, and in strong winds and low pressure it can come in faster than predicted.
Leave yourself a way back. Note the route you came in on and keep checking it while you shoot.
Watch the waves for several minutes before getting close. Larger sets arrive irregularly, and one wave much bigger than the rest can sweep a rock that looked dry.
Never turn your back on the sea.
Stay off wet, dark or green rocks at waterfalls and on shorelines; algae makes them extremely slippery.
Keep away from cliff edges, especially after rain, and respect fences and closed paths.
Rivers rise after rain upstream, even when it is dry where you are.
Carry a charged phone. In the UK, if you are cut off by the tide or see someone in trouble at the coast, call 999 and ask for the Coastguard; elsewhere, learn the local emergency number before you go.

No photograph is worth a rescue call. If conditions look marginal, shoot from higher ground with a longer lens instead.

The basic long-exposure setup

A sturdy tripod, pushed firmly into sand or set on solid ground. Waves washing around the legs will move it, so expect some soft frames.
A remote release or self-timer to avoid shake when you press the button.
Manual or aperture priority mode, low ISO and an aperture around f/8 to f/11.
A shutter speed long enough for the effect you want.

Choosing the shutter speed

Different speeds give very different looks, so experiment.

Around 1/4 to 1 second keeps some texture in waterfalls and shows the shape of retreating waves.
Two to ten seconds gives the smooth, silky look on waterfalls and softens the sea.
Thirty seconds to several minutes flattens water almost completely and streaks moving clouds.

Take a short and a long version of the same composition; often the in-between one is best.

Neutral density filters

In daylight, even at the lowest ISO and a small aperture, the shutter speed will be too fast for smooth water. A neutral density (ND) filter reduces the light reaching the sensor without changing colour much, so you can use longer exposures.

Strength is given in stops. A three-stop filter lengthens a 1/15 second exposure to about half a second; a ten-stop filter turns 1/30 second into roughly 30 seconds.
Compose and focus before fitting a strong filter, because the viewfinder becomes very dark.
Cover the viewfinder on cameras with an optical one during long exposures, or stray light can leak in.
Graduated ND filters darken only the sky, which helps balance a bright sky with darker water.

Many phones and cameras also offer a long-exposure or multi-shot mode that blends frames, which is a good way to try the effect without filters.

Waterfalls in particular

Waterfalls often sit in shade, so the light is softer and contrast lower, which suits them. Overcast days work well. Spray on the lens is the main problem: keep a microfibre cloth handy, check the front of the lens between shots and shoot from slightly further back if it keeps misting.

Seascapes in particular

Time your exposures with the waves. Starting a one-second exposure just as a wave pulls back from the rocks gives attractive trailing lines. Sunrise and sunset suit seascapes, and so does blue hour, when longer exposures are easier without filters. What is the longest exposure you have used on water? Share your results and tips in the comments.