I've been thinking about the old eyes and open sights problem and there might be a way to wiggle into something of a solution, at least for target shooting.
Pinhole glasses (stenopaic glasses)could increase depth-of-field enough to be helpful on the range when using open sights. The many pinholes in such glasses would allow the shooter to select one hole to use when sighting in. Further, the problem of diffraction could theoretically be reduced by limiting the wavelengths of light in play by using yellowish or amberish shooters' glasses in addition to the pinholes. Pinhole glasses are available online and shooters glasses are available almost everywhere.
If anyone tries this, let me know how theory relates to practice.
