It may have a name almost as long as its price tag, but the Nikon AF-S NIKKOR 180-400mm f/4E TC1.4 FL ED VR is nonetheless a pretty startling telephoto lens. It's the first ever full frame lens to sport an integrated 1.4x teleconverter. Simply flip a switch and the focal length changes to 252-560mm.
The lens maintains a constant f/4 aperture as you zoom though when the teleconverter is engaged, the aperture narrows to f/5.6.
The lens is loaded with new AF tracking algorithms and when paired with cameras that use Nikon’s 153-point AF system (such as the D5, D500, D850), the outer row of AF points are activated as cross-type sensors to improve AF coverage throughout the frame.
You’ll enjoy Vibration Reduction good for up to four stops of correction, per CIPA. There’s Nano Crystal Coating to help keep flare and ghosting at bay and a new ball-bearing tripod collar ring to make it easier to switch from horizontal to vertical shooting. There are nine rounded aperture blades that stop down to f/32 or f/45 when the teleconverter is flipped on.
Oh, and about the price. It's $12,400. But you're worth it, aren't you?