I love my Canon Rebel T6 and take portrait pictures in Av mode with a 50mm in 1.8 Av. I'm using auto focus in the 'focus on center point' mode. I make sure that the center point focuses on the face so the face should be the sharpest part of the picture. However, it isn't. Usually the auto focus misses by a couple of inches (focus and sharpness is best about 2 inches closer to the lens) when it comes to the sharpest part of the picture. So the face is never 100% sharp. Any thoughts on what I'm doing wrong?