I currently have a Nikon D80, and will at some point upgrade my camera (not sure when). But for now I do not have a wide angle lens current and would like to make that my next addition. Here are my current lenses: 18-135 Nikon Lens (came with my camera), 70-300 Nikon VR, & a Tamron Macro Lens. Any recommendations on a solid wide angle lens, that won't break the bank? Thanks!