Here are a couple of example photos of flowing water in a stream taken at 2 different speeds to show the varying effects you can get.
A tripod is preferred for slow shots like these but just experiment if you dont have one.
Note that the photos look very similar in layout so it can look as if the blurred one might have been done in software from the first photo. No, they were two separate photos. They have the same position because I used a tripod and wanted to have the same view for comparison. The fact that the water looks in the same place is because of the underlying rocks causing the same flows to happen – also the water was pretty fast running emphasing this flow.
The speeds you need to use to get these effects depend on how close you are and on how fast the water is running.
Best to set your camera to S (or M mode if you know what you are doing) . Also set your ISO as low as possible.
If you want slower speeds (say 2 seconds or slower) you will need an ND filter during the day or try the shots in lower light nearer twilight.
you can find more examples from this and additional explanations free on the Photofaculty Learning Zone
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