Shooting Water

When making decisions about photographing water, consider how you want the water to look. Both of these waterfalls were shot in Southern Iceland within an hour of each other in early evening, but have radically different looks. In the bottom one, "Horse Tail", the Seljalandsfoss (foss means falls), the water looks creamy/feathery because there is a long shutter speed (8 sec) allowing for a higher volume to pass by during the capture. In the top one, "Tumbling Waters", at Urriðafoss, the water has spikes as if frozen in motion because of a fast shutter speed (1/125 sec) that stops motion. Both were shot with an aperture of f22 at ISO 200. If my math is right, 1000 times as much water flowed by at a given point in the second than in the first.
Both effects are nice, but give a different feeling. In the slow capture, it is closer to what the eye sees and is dreamier. In the top photo, you have much more of a sense of how frantic and hurried the water seems as it rushes over the rocks. Getting the fast capture is easy and is probably what you will get by putting the settings on automatic. The longer exposure requires more work. To lengthen the time the shutter is open (shutter speed), you will need to decrease the amount of light-- use a small aperture (f stop) and either shoot at near dusk or dawn or add a filter that decreases the light entry (or both). For this one, I shot in the early evening and used a 4x (reduces the light to 25%) neutral density (ND) filter, courtesy of Tony Prower at Iceland Aurora Photography.
If you want to go low tech and using your iPhone or a point and shoot, you can use sunglasses to cover your lens and it will help. Also, thanks to Tony who guided us to these beautiful waterfalls and gave me many useful photo tips.