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.

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BrentD, (Professor - just for Stan)
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