I primarily use a single point for auto focus and pay close attention to my depth of field.
I have an iphone app that has replaced my old charts and is extremely useful.
I do wedding photography and make sure my sharpest focus is usually on my bride.
I then use my depth of field (near distance and far distance) to either assign the group or to change one of the
factors that affects my depth of field.(aperture or distance)

Still I have some occasional blurring at the edges of larger groups that is not accounted for in my calculations.

My question is:

Does the depth of field change toward the periphery of especially wider angle lenses?


Thanks