Set the AF point
Rather than letting your camera decide which AF point to use, take control yourself.
When a camera sets the point it tends to look for the nearest subject towards the centre of the frame, so if your subject is off to the side because you’re using the rule of thirds there’s a risk that it won’t be sharp.
Your camera’s manual will explain all you need to know, but you’re looking for an option called something like single-point AF.
Then, when you’re composing a shot, you’ll need to press a button to activate AF point selection mode and use the navigation controls to select the point that overlies your subject.
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