Do a search here on this site for the RR you need.This topic has come up several times, and people post links and references that may be helpful.

Some pretty good resolution for fifty-year-old photos......;-)

No problem.....so long as I can bring my "elastic tape". 😉

FWIW, since you already have a point on the line on the other side between "C" and "D" (which you appear to be holding as good), it is logical that yo...