Sketches are done using a combination of permanent black ink, Tombow ( waterbased ink pen) Micropen. and a water brush. I try to refrain from using pencil as it frees me from being too rigid and exacting while sketching. Also, if I'm hiking with friends and/or family or at an event, I do not always have enough time to do much more than a quick sketch or outline. My watercolor paper sketchbook is pocketbook or backpack size. The color you may see in a sketch is only from the three black "pen" types. When diluted with water inks "bleed" the various shades which make the black ink. ( I do occasionally use a burnt sienna Tombow or watercolor, but for most black and white sketches any color is a "happy accidents" from pen bleeds.) Requests for commissions of sketches are welcomed and you may note I've made prints of some, however, the originals are in the "books" for reference and not sold.