Catpiano

Doesn't matter what model ..  

You can turn off the face detection feature, or select your focus point from your menu.

Catpiano

Evaluative .. center weight .. average .. spot ..  are NOT focus .. they are NOTHING to do in focus ..   

Those are METERING ..  mean ..  calculate how much light is need ..  and how much time is need for a pic ..

Make it simple .. like you are filling up a water tank ..  the bigger and higher pressure hose to use .. the less time is needed ..   that is the relationship between shutter speed ( time ) and ampture ..  ( how big the space to allow LIGHT to get though .. )