It has to do with the shutter speed
The question comes up frequently here at Nikonians; "How do I get that milky look of water in rivers, streams and waterfalls?" It seems to hold a certain magic. Others may want to freeze the water to a certain extent, as if suspended in mid air. The answer how to do it is of course in the shutter speed. But how slow or how fast? Below is a set of illustrated options at a wide range of shutter speeds.
Rainbow Falls, Great Smoky Mountains National Park
1st Nikonians Photo Adventure, October 2001
Nikon F5 on Manfrotto 055 tripod, 80-200mm f/2.8D ED IF AF-S, L37C filter
Exposure: f/22, 8 seconds on Konica Impresa 50 negative film
Click for larger image
It has been important to remember that whether one chooses a very slow shutter speed or a not so slow one, a sturdy tripod is a must for this kind of photography.
To achieve slow shutter speeds you may need to resort to Neutral Density solid filters, whether the resin rectangular ones on a holder, or the glass screw-in type making sure you choose a multicoated one to avoid nasty reflections.
|* The red rectangle shows the area from where the sample images were extracted. The person (small white dot) in the upper right corner was asked to pose there to give an idea of the proportions of the waterfall.
This article on why shooting raw is having examples using waterfalls
We are discussing waterfall photography in our landscape forum. Here is one such discussion
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