Checkout this Nikon 1200mm f/11 lens - Nikon Rumors
AF-S NIKKOR 800mm f/5.6E FL ED VR
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Amazon.com : Nikon AF-S FX NIKKOR 800mm f/5.6E FL ED Vibration Reduction Fixed Zoom Lens with Auto Focus for Nikon DSLR Cameras : Camera Lenses : Electronics