Let me introduce you to Natalie Niblack. Well, actually this isn't Natalie but it is just one of her inspiring creations. I studied under Natalie when I decided to take on my first Art class in college; Drawing to be exact. She was an awesome instructor and managed to help me see exactly what I was made of, and I have to tell you that I was managed to achieve alot more than I initially thought possible - by applying myself and working really, really hard.
Looking at this sketch now - after the 3 month course - I am even more amazed at her patience and attention to detail. This sketch was accomplished with the use of graphite and a hell of a lot of time. This may look like a small piece in this little window but most of her sketches are done in life size format. Yes, life size as in 5 ft. I, myself, find it extremely difficult to stay focused for long periods of time but after being in Natalie's class and having to spend 3 hours sketching a nude, it does get easier.