The standards we
use in variety collecting and attribution have been in place for
over three decades and thus are well established. Cherrypickers prefer a 10x loupe, usually of the Hastings
triplet type, such as the one manufactured by Bausch & Lomb.
The Hastings triplet is composed of three layers of optical
glass. So it offers high magnification with no distortion
around the edges. There are several reasons why this standard
was established. It is affordable (still around $40.00). It is
portable (easy to carry at coin shows). It allows you to see
almost the entire side of a Lincoln cent with one glance.
Furthermore, 10x is the standard for listability. If it
requires more than 10x to see the variety, it is not listable in
the CONECA files and thus probably not worth your time and money
to collect. Once in the study, a 20x-30x microscope is
used to identify the die diagnostics and confirm an attribution
of the variety.