Thats a beatiful picture and i am a huge fan of Frank Herberts movie Dune.. its a great movie and the sequal "Children of Dune" was also wonderfully done. You should post a few more pictures if you could of Dune. Maybe of the Great Spice Worms or of the battles between the Baron and the Duke in the beginning of the story. I would really like 2 see you draw a picture of one of the worms though. Neways great picture. I havent seen any pictures of Dune on deviant art and i suspect that there are very few. Nice job with the detail and how you capture the life on the planet with the spice miners and the freemon.
Great detail and composition, I'm not familiar with the characters so can't say if it's a good likeness [although judging from previous comment it is]. I really like the use of colour to emphasise the foreground figures
Technically, probably, but given the vast number of people who run, say, prints of Harry Potter, I doubt anybody's really going to sue me. I have friends who do decent business in fanart and they've never had a problem, so I assume they don't go after you until you seriously make money.