I have recently taken an interest in lightning photography. Have been using the standard 18-55 mm Nikon lens with good results. However I would like to get a lens that would give a wider angle of the sky. Read an article that stated prime lenses as being more appropriate for the photographer on a budget. All I need is a wider angle of the sky. That means less photographs missed during a storm. Could someone recommend a less expensive wide angle lens with the model number. That way I can look up the price etc.....