Before I had cataract surgery, there were two things which I found helped. The first was that I shoot a long barreled muzzle loader and putting the rear sight about 14" down the barrel made it a bit easier to focus both the sights and the target. Also I use a pistol type sight on my gun ; in other words a flat topped square notch at the back and a flat topped post in the front. As my eyes continued to age, I have some "computer glasses" made which focused at about 36 - 40". It gave me 100% vision of the sights and about 95% vision of the target out to 75 - 100 yards. My eyes continued to age, with my right eye in particular being quite foggy and cataract surgery cleared that up completely and while I still need a weak prescription for 100% vision, my vision is clear and sharp. I intend to get another pair of glasses that focus around 3 feet or so which in addition to being able to see both my computer monitor and writing close to me, will probably give me better vision of my sights and still retain fairly good vision of the target
cheers mooncoon