On an excursion in the Columbia River Gorge in Oregon, I took a handheld one second long exposure. While one second doesn’t seem like it makes a difference, it completely changed the feeling compared to a faster shutter speed. The results show why the blurred, smooth look for waterfalls remains popular.
Generally speaking, a photographer wants to capture the true essence of the natural environment. However, many focus on processing techniques that reach the scene’s true color. It’s true the differences between the camera and human eye are sometimes only fixed in post. However, aiming to get as many factors right as possible in-camera is the best approach.
Determining the correct long exposure for moving objects like water sits among those considerations.
Differing long exposure experiments
Considering that 1/500 of a second moves faster than the human eye, I headed back into the gorge to find the best speed to replicate my experience. A five-second long exposure didn’t produce much difference than the 1/2 second exposure. One-third second resulted in significant blur and captured more character of the waterfall. Finally, 1/60s, generally considered the slowest recommended shutter speed for handheld shots, resulted in slight blur.
In terms of speed, the one-thirtieth of a second produced the most realistic result. The human eye sees more water detail in person but the fast movement of the water results in smoother-looking water. While environmental and lighting conditions vary, this long exposure setting appears a good starting point because it produced a good mix of detail and motion.
The observant notes that a marked color difference in the longer shot. Changing lighting conditions and effects on exposure iterates that no hard and fast rules apply.
Expectation determines perception
A good majority of waterfall images contain blur due to either deliberate choice or technological limitation. When photography started in the Gorge in 1867, the first images of long exposures contained lots of motion blur. Even with modern technology like iPhone cameras, waterfalls still contain motion blur. Some falls receive lots of natural daylight, which makes them easy to photograph without slowed shutter speeds. However, many other falls receive heavy shade and require long exposure.
Some blur feels natural due to the Coconut Effect. The human eye sees waterfalls in pictures more often than in person. These images shape our mental image of waterfalls and determines whether a photo looks natural or surreal. Visitors to the Grand Canyon see this effect because the rocks are more vibrantly red than what photographs tend to capture. Many photographers find that their images feel over-saturated because of it.
Long exposure recommendations
No perfect shutter speed exists because it boils down to lighting conditions, desired results and personal taste. It also changes due to the nature of the subject and the feeling a scene’s movement evokes. However, creating projects to experiment that find starting points that best suits aesthetic goals and needs consitutes excellent advice.
Additionally, simulating long exposure with multiple images in post is another possibility to capture detail that accurately portrays the experience of a scene. Remember that deliberate practice and purpose helps complicated processes become second nature.