nano-Crystal coat is the latest and greatest in anti-reflective coating.
Normally a refective coating is only good for a certain range of the light-spectrum. this is why every reputable lens-manufacturer has "multi-coating" to cover all the relevant spectrum and make more light go through the lens and not reflect off the lens-surface.
This is since the dauy of DSLRs a very special problem at the rear of the lens, as the sensor of a DSLR reflects more light back to the lens than a film does! So there very numerous efforts to avoid that light reflected from the sensor is then reflected back from the back of the lens and go haywire on the sensor again.
If Nikon is making the "N"(=nano-coat)-designation obligatory for FX-lenses all the better. Still all the FF-lenses do also serve their FX-sensor. So again, they are playing marketing games with us
Pretty critical for a Nikon-fanboy, huh!
Thomas (beware: Nikon-fanboy and moderator!) My Lens Reviews
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