What's the most work you've ever put in to getting the shot you desire? For Arctic photographer Audun Rikardsen, it took three years of planning, one motion sensor and a hole drilled through ice to get within touching distance of this dramatic, award-winning wildlife image. A Seal's Last Sight has won the Grand Prize at the California Academy of Sciences' 13th annual BigPicture: Natural World Photography Competition. It was chosen from more than…