The 17-35mm f/4 Pro FX Lens for Nikon Cameras from Tokina is designed for use with a Canon full frame digital or film camera. This ultra wide-angle lens gives you a 103.9? angle of view at the 17mm end of the zoom, and a bright, constant f/4.0 maximum aperture, making it ideal for low light photography. Two Super-Low Dispersion glass elements and one aspheric glass element produce superior contrast and sharpness, and help control chromatic aberration. Tokina's One-Touch Focus Clutch Mechanism provides a quick and simple way to switch back and forth between autofocus and manual focus. The lens has been designed using improved seals, making it "water-resistant" (not waterproof), so that damp conditions won't spoil your shooting expeditions. The lens features a water-repellant optical coating, but is not safe to submerge in water or expose to heavy rain.