This morning I painted in a field next to my church (a regular occurrence now, after my men's bible study). There were two combines and a terrific old blue truck out there, and I couldn't resist.
After finishing the painting, I decided to grab my sketchbook and get a more detailed drawing of the machines. The lighting had dramatically shifted, since it was about noon when I finished adding color. These were mostly in cast shadow, so no highlights to speak of.