I painted a watercolor demo during a daylong visit to Favilli Studio, a multidisciplinary design group in South Pasadena.
I walked down to the Arroyo with a group of designers and chose this view toward the York Avenue Bridge. I wanted to paint the forms—arch bridge, trees, and embankment—as realistically as I could.
But the light was overcast the whole time, so I decided to invent some light and shadow effects.
I figured that I could make the planes of the retaining wall much more clear if I cast a foliage shadow across it, with the dappled spots of light following the vertical, horizontal, and diagonal planes.
The cast shadow serves two purposes. It invites the viewer to move from the dappled foreground shadow, where they seem to be standing, into the brightly lit middle ground, where Jeanette is standing.
The foliage shadow also helps to define the plane changes as the ground slants up and over the embankment wall.
Shadows can be a powerful tool for expressing plane changes, as Arthur Guptill demonstrates in this plate from Color in Sketching and Rendering (1935).
Learn more methods in my video Watercolor in the Wild