Per darling endmyopia reader Ron, who e-mailed us his contraption photo. At 74 he’s now working on reducing his myopia!
Pic above, a combo device that measures both distance to blur (focusing on the central letter “o” under the pivot pin is all that is needed) as well as astigmatism. The dial is glued to a thin sheet of flat plastic cut from the lid of a food container.
Included in the updated astigmatism measuring DIY article, along with the updated high resolution printable tools.