In a 3 hour open studio session, you get about 2 hours of actual work time. I am increasingly convinced that this period of time is mostly insufficient to produce anything but the crudest sketch - at least for me at this time in my development.
More time and work required!
However, I have to say that even as rough as these last few pieces seem, there is a freshness about them and a loose quality that I am really liking. And the time painting them is just beyond fun! 
