To spot subtle patterns in water, look where dark and light reflections touch each other.
On calm days, the surface of water can appear still, but it is never perfectly flat. There are always some gentle movements and ripples to be found. All these small motions are signs and clues and reveal what is happening near, on, in and under the water.
If we focus on the dark or light areas (nearer the top and bottom of the video above) it is hard to make out any movement. But if we focus our attention where light and dark reflections meet then suddenly we can spot the gentlest of movements and ripples in the water. Try looking at reflections at the edge of the trees.
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