The newly acquired four generations of Xiaohei were out of focus on 40 days.

The first question: No, because the fine-tuning of 50D focusing is based on reading the lens. Reading the lens first and then saving the lens data, or saving it in the camera and fine-tuning the focus, will be automatically saved. You didn't save the data of fine-tuning the focal length in the lens ... If you think about it clearly, you will know that you can't put it on the 40D after adjustment. Send it to the factory for repair! Don't go to the small repair shop ... it's getting more and more troublesome.

Manual focusing and autofocus are the same without out-of-focus, but your Sigma 70-200 at 100% is definitely different, because autofocus itself is still optimized, but the focus should be similar. If you focus on the divided image focusing screen, the focus should be the same.