Portraits engage the left side of my brain because they require engineering and precision - the flip side to the spontaneity that I enjoy when I paint from my imagination. I often paint upside down, a counter-intuitive measure that assures I paint more precisely (e.g. what I see, not what I think I see).
Painting John Donaldson was especially rewarding. I took over 100 photographs of him in various locations, including close-ups of his face and details of his hands. Here is the work in progress (hover over the image for a description).