Since the introduction by Tamron of the first Nikon mount lens featuring an internal AF motor, all Nikon mount lenses with the internal AF motor had used the classification code “N II.”
Lenses using a coupler system – a shaft harnessing the AF motor built into the camera body to operate the lens – without an internal AF motor were designated as “N.”
Tamron says that, because future Nikon lenses will have the internal AF motor as a standard feature, the company has decided to simplify the designation and consolidate all Nikon mount lenses as “N.”
The “N II” designation is being deleted for future models.
This classification code change will be effective beginning with the 18-270 mm f/3.5-6.3 Di II VC PZD.