The world’s lightest FX-format compatible, super-telephoto 500mm f/4 lens that employs two fluorite lens elements. Two fluorite lens elements and three ED glass elements plus Nano Crystal Coat are employed to achieve high optical performance with minimized chromatic aberration and ghost effect. VR performance immediately after the power is turned on in NORMAL mode has been improved, providing a more stable viewfinder image and enhanced blur-reduction effect on the resulting images. Even during high-speed continuous shooting, superior AF tracking is achieved, while exposure is stably controlled with the adoption of an electromagnetic diaphragm mechanism.