[davidmanze]

         Could be that Sigma have decided to take a slightly different route with their 24-70, it's 2/3rds the length of the Nikon and extends, the Nikon is 45mm at MFD at the 70mm setting, so another style that maybe sacrifices a little sharpness wide open for no breathing and a shorter but fatter profile.

 

 

 

   I certainly like it's look!

 

 

  Ah the images of the lens in it's contracted and extended form have been "blocked in this community", they post fine in DPreview,  strange!