Posted on March 9, 2018
One of the questions I’m asked most is how to blur water. It’s really not that hard when you know how to control your exposure variables, and in fact if you’re photographing moving water in the right light, it’s easier to blur the water than it is to freeze it.
Here are the essential elements for blurred water:
With these basic ingredients, and a little knowledge of exposure management, you’re ready to go. While motion blur requires the shutter remain open long enough for the water’s motion to blur, there’s no magic shutter speed that achieves this. The amount of blur will vary from a lot to none at all, depending on the following factors:
Most of the above motion blur factors affect the composition too, so achieving motion blur without compromising the composition usually comes down to managing the shutter speed. Choosing a shady scene or overcast day is a good start, but here are a few other ways to keep the shutter open longer:
Armed with this knowledge, you’re ready to go. One important thing to keep in mind is that motion blur is never just blurred or not blurred. Rather, there are degrees of blur. That’s why, when possible, for any given scene I try different ISOs and f-stops, adjusting the shutter speed to compensate and vary the blur effect.
In a region packed with waterfalls, Upper Horsetail Fall (sometimes called Ponytail Fall), is one of my favorites. After a short but steep hike from the road and (lower) Horsetail Fall, hikers round a bend for the first view of the source of the roar heard from several hundred yards down the trail. Most waterfall trails either cross the source river or creek upstream, above the fall, or down stream, below the fall. The Upper Horsetail Fall trail goes behind the fall.
On this visit, before venturing behind the fall, I scrambled down the slope on the right and set up near creek level, in front of the whitewater and just downstream from the pool. After a little bit of visual exploration, I settled on the essence of my composition: the rushing water in the foreground, with the waterfall prominent in the background, balanced by the brilliant green of a freshly leafed-out tree. The compositional variations mostly centered around how much of the fern-infused rock on the left, and the angled tree trunk on the right, to include.
Another compositional choice to weigh was whether to allow the foreground rock to merge with the rock just behind it, in the center of the creek. Normally I try to avoid merging elements at different distances, but in this case the solution would have been to move a couple steps to the right, which would have put the fall more behind the tree. Since the waterfall is the scene’s most prominent element, I decided to maximize its presence.
The darkness of the surrounding forest was enhanced by a thick overcast, making motion blur virtually inevitable, so I just embraced it. Often the greatest difficultly with photographing motion blur surrounded by dense foliage is that a shutter open long enough to blur water is also open long enough to pick up wind motion in the leaves. On this morning I was fortunate to have virtually no breeze, and my 1-second exposure blurred the water and froze the leaves. Mission accomplished.