Nikon’s optical engineers have overcome a number of technical challenges to incorporate a switchable 1.4x tele-converter into a telephoto zoom lens. 
 
The new AF-S Nikkor 180-400mm f4.0E TC1.4 FL ED VR is an ‘FX’ format lens (i.e. 
for use on full-35mm Nikon D-SLRs) and, with the extender switched in, becomes a 252-560mm zoom with a one-stop loss of speed to f5.6. However, it can be used on Nikon’s current ‘DX’ D-SLRs, in which case the effective focal ranges become 270-600mm and 378-840mm respectively.
 
The 180-400mm f4.0 zoom measures 36.3 centimetres in length and weighs in at 3.5 kilograms. It incorporates Nikon’s ‘Vibration Reduction’ optical image stabilisation which is claimed to give up to four stops of correction for camera shake… if you should be courageous enough to try using this lens hand-held. The optical construction comprises a whopping 27 elements in 19 groups which includes one fluorite type and eight made from glass with extra-low dispersion characteristics to optimise sharpness. Nikon’s ‘Nano Crystal Coat’ multi-coating is used to help suppress ghosting and flare.
 
 
Focusing is via an internal lens group with a ring-type ultrasonic drive for autofocusing. The minimum focusing distance is two metres which, at 400mm, still gives a maximum reproduction ratio of 1:4. When the 180-400mm is used on Nikon’s high-end D-SLRs with the current 153-points AF systems (D5, D500 and D850), the outer row of points become cross-type sensors to give improved coverage with enhanced acquisition of smaller and/or fast-moving subjects.
 
There’s a nine-blade diaphragm for smoother out-of-focus effects and a rear filter holder which accepts screwthread types with a diameter of 40.5 millimetres.
 
The external construction employs magnesium alloy barrel tubes with sealing against dust and moisture plus a fluorine coating to reduce the build-up of dirt and grease plus allow for easier cleaning. A newly-designed ball-bearing tripod-mounting collar ring is designed to enable quicker and smoother switching between the horizontal and vertical orientations. Like Canon’s EF 200-400mm f4.0L IS USM Extender model, the integration of the teleconverter in the 180-400mm results in a distinctive ‘bulge’ at the back of the barrel (where the converter is parked when switched out of the optical path).
 
Given all the other numbers associated with the AF-S Nikkor 180-400mm f4.0E TC1.4 are big, not surprisingly the price is too. As usual, Nikon Australia hasn’t issued an RRP, but Camera Electronic in Perth – a local Nikon Authorised Reseller (visit www.cameraelectronic.com.au) – is listing it at $18,500. Availability is from March 2018 with purchases made from Australian retailers backed by a two-year warranty. 
 
For more information visit www.mynikonlife.com.au