I know that image quality suffers with using EF 2x III extender, I was wondering if adjusting the sharpness (or other settings) in the camera would help compensate for the degradation? Or would it be better to adjust the RAW file in post processing? This is a question I have wanted an answer for and finally got motivated to ask it, rented the EF 100-400mm f/4.5-5.6L IS II (coming Monday) and want to try my 2x III with it. Thanks in advance for your help.