One of my loyal "blog followers" has asked about rendering "moving" water, so I sat down for a few minutes this morning and put together this demonstration. I broke this down into progressive steps, which will make it all easier to digest. There's actually a lot going on here, so doing it in a logical sequence is by far the easiest way to approach it. I put this on a black background simply for better clarity and contrast ( just for the sake of the lesson ), but you would obviously use lighter, more appropriate background colors to match the particular scene you're conveying.
Photo #1 - Sketch/Layout/ Placement of the wave shape
Photo #2 - Basing in the bulk of the wave trough. Notice that the direction of the wave is already apparent in this early stage. This is of the utmost importance. Waves move in a "corkscrew" motion and they can flow to the right or the left ( that is up to you ), but they require movement!! Also, note the lighter "eye" at the peak of the wave which lends a somewhat translucent quality. It's a MUST!!
Photo #3 - Adding the "dump" of the wave ( see it crashing over? ) and the "shadowed foam" along the crest.
Photo #4 - Highlighted ( white ) foam was added on the top of the shadowed portions. Think of your light direction and don't just outline the whole thing. That's boring and mundane. It's much more dramatic ( and realistic ) to add a touch here and a touch there. Some "spatter" ( thinned white on a Fan brush ) really makes the water move and churn. Foam patterns ( wave lines ) were added with a Scrpit brush and thin paint, first in a shadow tone ( blue and white ), then highlighted with white alone. These must follow the established wave direction.
For this demo, I used only a Fan brush and Script Liner. Colors used were Cobalt Blue, Permanent Green Light, Cadmium Yellow Pale Hue, Van Dyke Brown and Titanium White.
I hope this helps anyone wishing to improve their water painting skills.