(big image file)
I been doing 40-50 minute sketches on sketchoholic.com with the Imaginism crew. In the sessions or marathons, you have 1 hour to draw/paint the idea/topic and then vote on your favourite one at the end. These are some recent ones I did in the past 2 weeks(there's more but I just selected the better ones haha). It really helps you think faster and get ideas down faster when doing these. The ones before I could hardly get just the tonal B/Ws done in the 50 minutes, but I've been able to use colour soon after that, it's good practice and good for warmup haha. Last 2 pics are studies.