I stumbled on this article by Mr Rockwell 
And now I'm curious to find out what's the relation between the number of blades in a lens and the image quality. In that article he said that the latest version has only 6 blades and that's inferior....but I'm not sure in what way.
Maybe the masters here can enlighten me a bit ;p

And now I'm curious to find out what's the relation between the number of blades in a lens and the image quality. In that article he said that the latest version has only 6 blades and that's inferior....but I'm not sure in what way.
Maybe the masters here can enlighten me a bit ;p