Hi Georgia, not sure if I understand what you mean: manual focus assist doesn't "sharpen" anything, it just "shows" in the viewfinder what IS in focus. Of course you can disable it, but things will be in focus, even if there will be no red underline around in your viewfinder. If you look for out of focus images, and you are using manual focus control, try to focus on something very close to the lens, something around 50cm, then take a photo on something at 2 or 3 meters