[Brightcolours]

Thanks BC!

                   Does the Nikon AF105mm DC (defocus control)  lens use the same principle and how does the adjustment ring work?  Personally I would much rather get a S/H copy of that lens as it has it all, it's one of Nikon's sharpest and best built all metal lenses and a built in lens-hood.

No, Nokkir's DC lens does not use a similar technique. It moves an element to either make the background or the foreground bokeh smoother. And it allows you to muck things up by setting the DC ring to a setting for a different aperture, making everything blurry.