From value to color
This has been my favorite exercise so far at the Marc Hanson workshop. The idea was to paint a simplified three value study (upper left), then do the same thing again, but continue with a few half-tones and dark and light accents (upper right). I found that the simplification showed up flaws in my design, and I was able to correct them.
The next step was to mix colors for the three values, and for this scene we mixed two colors of the mid value (the blue and the lighter green). This is what I wanted to learn, how to mix the color with the right value. And Marc showed us a trick; put a dot of your color on the value painting, squint, and you can see if it is too dark or light. It really works, can you see my color dots on the upper left painting?
I got so much out if this exercise, I'd like to include it in my process for a while. You've got to work fast though, to do a value study and color study before the light changes.