I love going out to do quick sketching on location. It clears my head, gets me away from daily work issues and allows me to try new ideas. The method I have been using is to combine Tombow Pens, fine point Sharpie, and blend with a Waterbrush.
I have recently started trying more extreme formats: long skinny verticals or narrow panoramas. This sketch to the left was done on a 5.5″ x 8.5″, 140 lb watercolor paper sketchpad. The black lines are Sharpie which is waterproof and all the color is Tombow Pen and Waterbrush.
The images below show a progression of how I work with this method.
1. Black fine point Sharpie
2. Bright Tombow Pen for under layer
3. Black Tombow Pen for value
4. Blend and bleed with Waterbrush