The main question is how and where are you focusing? The full file I looked at seems okay, but for best results I'd stay wider than f/11 to avoid diffraction.
Why are you using shutter speeds of 1/50 and 1/60. You could just be getting blur from camera movement. Redo the shots with a decent shutter speed and use something like f8 which is a sweet spot for the lens. You cannot really tell anything from these shots IMO.
