If I may...
Dial up the contrast
Dial down the brightness
Do a High Pass Sharpen (other sharpen routines would also work)
I don't think there's anything wrong with your lens, your camera, or you.. I think you just need to make a few adjustments in your processing or change the way the camera is saving the JPGs. Unless the detail is there, this is nearly impossible and this was done with a small 100k file.
Yes, it's still a little soft and there may be a little camera shake here. If you start with a RAW file (PEF or DNG) you might be surprised at what you can pull out of your files.
.... but I don't think focus adjustment is going to change anything here. That's just my theory though, I've never even seen one of these lenses in person let alone used one.
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