Well not sure about the range, At a full strength rx I need reading help, but if I crank down the myopic correction by 1.25 diopters,it must put me in the middle of that range where I can read Ok and still see well enough at distance.I ran this by my opothomolagist,and he agreed that it was ok to give it a shot,that it may work...It did..Your comments are interesting, thanks,,
Bud