It is my understanding, please correct me if I'm wrong, but doesn't adjusting the objective lens both focus and correct parallax for the designated range? Yes or no?
And-- I have just acquired a Simmons Pro-Hunter 4-12x40 scope with a focus adjustment on the left side of the turret. That I can clearly see does correct the focus for various distances but does it also correct parallax? It is not marked for distances you just eyeball it and turn the dial until you get a satisfactory focus.