I think, in all fairness to the lens, and I have to admit that I paid an incrediby high price for my copy of this lens (
I think it was $10
) complaining about image quality wide open is not really a true indication of what this lens can do.
i have attached a crop out of a shot taken (OK stopped down in sunlight) with my K10. This is with no resizing to show the detail it can deliver.
the entire leaf, from a horse chessnut, is this sharp, across the entire image and with good depth of field.
Maybe I am a little defensive of spending so much on a lens
, but I think it is all about knowing the limits.