Before setting up my tripod and camera, I frequently use a smartphone to preview potential compositions for still photography. However, the smartphone is especially beneficial in "pre-visualizing" patterns in moving water.
The rapidly moving water of cascades and waterfalls — especially when flowing over irregular rocks — generates repetitive patterns that will be evident in a photograph taken with a tripod-mounted camera using a slow shutter speed. But they are not so easy to see in person.
I suspect most of you know this tip, but you may find it helpful if you don't. A few years ago, I learned about the "Live View" function in the smartphone camera. When Live View is enabled on the smartphone, the camera takes a few seconds of video with the snapshot. When reviewing the image on the phone, the user can see a single frame of video that either loops, bounces, or is merged into a single still photograph (slow motion).
I find that by using the "Live View" function and selecting the "slow motion:" option when reviewing the image, I can get a fair idea of what my photo will look like using my tripod-mounted camera and a slower shutter speed. The best "pre-visualization" will come from a tripod-mounted smartphone with the option to control shutter speeds, but even a casual hand-held snapshot in Live View is helpful.
This is a hand-held smartphone snapshot of the Little Qualicum River cascades. It is not too different from what I saw in person, but it didn't show me what a photograph made with my digital camera using a slower shutter speed would look like. In other words, this didn't help me "pre-visualize" my photo. Smartphone photo by Donald J. Rommes.
Using "Live View" on my smartphone, I saw the same image as before. However, when reviewing the photo, if I tapped "Live View." I could choose between "Loop," "Bounce," and "Slow Motion." By selecting Slow Motion, the frames of the brief video comprising Live View were merged into this still image. Since only the water moved during the Live View exposure, the water is blurred, but the rocks are not. The flow patterns are better revealed, and although the water is too blurred for my taste, the image is a better "pre-visualization" of the photo I will make with my larger digital camera.
This is the photograph I took with my tripod-mounted digital camera. The view is broader and more horizontal than the smartphone photo, and the shutter speed was adjusted to get the desired balance between movement and detail in the water. Still, I think it is clear how the smartphone helped me "pre-visualize" my composition. A longer shutter speed on my digital camera would have resembled the smartphone photo more closely. Photo: © Donald J. Rommes.