Tokina 17mm f3.5 RMC - Nikon F mount
Great wide angle full frame lens. Nikon F mount so it can be adapted to everything. Our friend Ken Rockwell writes the following regarding this lens: "Want a lens that can give you great, eye-popping ultra-wide images for cheap? Get one of these! It works great full-frame. Its sharpness is better than many newer and more expensive lenses"