Until my last prescription, my eye doctor fitted me with glasses that 1) let me use my strong right eye to focus on the front sight, and 2) a left lens let me see the distant target clearly. No bifocal or trifocals.
Since focusing on the front sight is what's critical -- you need not see the target clearly -- that worked well.
My left eye has a small cataract right in the middle (not big enough to justify doing anything, yet -- and it may be a year or two), but it has affected my distant vision a bit.
This time, the doctor said he couldn't fit me with a lens to give clear distant vision this time -- as it might cause dizziness when I used both eyes while shooting. He suggested that I simply get a pair of reading glasses at the drug store and use them. I did, and it works well.
For slow-fire range work -- not competitive shooting (I do IDPA) -- a Merritt Optical Attachment, a small, adjustable aperture that attaches to your dominant eye's lens by suction cup, works ver well. That lets you see front, rear, and target clearly. I've had one for years, and there are times when nothing else will do as well.
