Hope it's ok asking in this section.
Trying a Kenko 2x extender with a 70-200 2.8 lens around park today it was great in nice light but back focused in shaded areas.
Was using centre point only without recomposing so know exactly where it should have focused.
Is this typical?
Edit - Forgot forum software had collapsible page menus. Please delete. Found the lens page.

