1. Have you uploaded full frame images or have your cropped them?

2. did you knowingly not use IS?

3. To remove the human variable, it would be good if you just place your lens either on a tripod, bean bag or some support. Then place a newspaper front page with headlines as well as smaller sized print on a wall. Click one image with manual focusing and another with auto focus. Better to use your inbuilt timer of 10 seconds. That will completely remove the shake. We can then see if the camera is failing to autofocus. Sorry for asking this test, as I would like to completely remove the human element and be sure that the equipment is failing to autofocus. I have used this lens for a long time and am highly satisfied with that lens. Did you buy the lens from authorised place or from grey market?

Cheers,
Sabyasachi