A brush with sunshine and a brush with shadow!

Bill is using two brushes to save a bit of time creating the sunlit and shadow waterfalls. Please notice at the :40 second mark how carefully Bill lays the brush on the canvas before he applies the stroke.

Also notice how careful he is to avoid “dirtying” the brush with the dark under color. Too many strokes without cleaning the brush will destroy the effect of the sunshine hitting the water.