The eye/brain is very good at seeing lines, and can see lines thinner than the usual 1 arcminute given as the resolution of the eye. 20/20 vision is based on reading letters that are 5 arcminutes high that have 1 arcminute features (line width and gaps). So this might give you an idea of how big to make lines and numbers on a sundial, although I would guess that you shouldn't require 20/20 vision among the viewers.
- Sundials at Train Stations Clarkkr
- Re: Sundials at Train Stations Roger Bailey
- Re: Sundials at Train Stations The Shaws
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- Re: Sundials at Train Stations Claude Hartman
- Re: Sundials at Train Stations Sara Schechner
- Re: Sundials at Train Stations Tony Moss
- Re: Sundials at Train Stations Bel Murru
- Re: Sundials at Train Stations Tony Moss
- Re: Sundials at Train Stations Richard Koolish
- Re: Sundials at Train Stations Patrick Powers