Would welcome some advice on an issue I have with my scope. I find that if I'm closer than about 70-80 yards to a deer, it becomes blurred. I have a Nikon ProStaff 3-9x50. I use reading glasses (when reading, not when using scope), but my distance vision is fine. I was wondering if I should get a scope with dioptre adjustment - is that how I can compensate for this? Reason I ask was I was thinking of getting a S & B 8x56, and I don't think it has dioptre adjustment, and if that's what I need in order to ensure nearer objects are not blurred, it rules it out. Hope that's clear, and thanks in advance for any advice!