Sketches in the Fog

In the fog, it was easier to focus differences between colors and light....which may sound strange.  I began drawing the willow beside the canal and as I drew the white fog around its leaves and dark branches wiped out the immediate scenery behind it.... the only other significant component to me was the framing composed by the bridge, other tree, and railings.  This same line of thinking carried on until I realized how much of the fog had lifted, which can be seen in the bottom sketch.