In the next 1-2 years Nikon is rumored to upgrade their remaining high end tele-lenses with fluorite element (FL) currently only present in the Nikkor 800mm f/5.6 ($17,896.95) and the Nikkor 400mm f/2.8 ($11,996.95). The list of upgrade candidates includes the following lenses (most of them are currently back-ordered in the three major US stores):
More information on Nikon’s new fluorite coating can be found here.
