Basically wht HalfaDouble said. The drug forces you into a constricted lens. A peep sight/tang sight/stick-on-glasses aperture does the same thing without drugs and without forcing you to live with the constricted lens all the time, which is a big downside.
Aperture sights can be fitted with weak diopters or you can put on on a pair of inexpensive glasses that have a weak (+0.5 or +0.75 diopter) that does the same thing.
Halfadouble, were can I find the Gehmann adjustable? I've not heard of that particular one.
I misspoke when I said, earlier, "iron sights", I meant open sights. In the crowd I used to run with and compete with that meant notch and post (open) iron sights. Of course, iron sights can mean aperture sights. I competed many years with both, and understand how a rear aperture can help aging eyes to clarify the front sight and the bullseye. I use, and have used, a Merit adjustable aperture rear for over 30 years, with much success.
So, back to my question, which I will reword.............. how can these eyedrops help aging eyes to shift focus from the front POST to the rear NOTCH, and back and forth, until settling on the front sight and breaking the sear?
