This was done entirely with pencil, so it was only about 20-30 minutes. I haven't done much hand coloring with the Art 300. Working this print took longer than it would on MGIV mat. The paper's "tooth" makes it harder to blend the pencil marks, slowing the process down.
I've done some very lengthly hand-painted photographs in my time....The least amount of time I ever spent was probably 3 hours...this looks like it would have taken a very long time...impressive amount of dedication.
Thanks, all... When I work with oils they take much longer. Pencils are quicker. My technique is to rough up the lead, with fine grit sandpaper. The color goes on unevenly, but I blend it with pink tipped eraserstik style erasers. I also use the sandpaper to shape, and clean, the eraser. For a simple 6x6 inch version, like this, it goes quickly. I spent about 25 hours (off and on) doing an 18x18 inch version of this, which is a combination of oil and pencil: http://www.apug.org/gallery1/showimage.php?i=65226&catid=member&imageuser=7387