I have used Zeiss, Clave, TeleVue, RKEs but the eyepieces I love the best are
the oculars known as the Brandons for my lunar and planetary observing. Brandon
is a brand name of VernonScope, and is applied to a variety of products,
including a well-established line of eyepieces. Several of the short- to medium
focal-length Brandon eyepieces are advertised as orthoscopics, yet they appear
upon disassembly to resemble Plossls. They use four lenses in an unsymmetrical
duplet formulation designed by Chester Brandon, one of the designers of the
top-secret Norden bombsight, which played an important role in World War II.

Brandon eyepieces are a popular choice of professional astronomers worldwide.
VernonScope estimates that over one million Brandons in various incarnations and
focal lengths have been produced since their introduction in the early 1940s.
Designed for medium to high power use with any telescope at focal ratios down to
f/4, they are very sharp at the center (although somewhat less so at the edges)
and ideally suited to lunar, planetary, star cluster, and binary star observing.
They have excellent color correction and very low astigmatism, with very minor
field curvature and ghosting. They are fully coated, but not multicoated, in
order to reduce a phenomenon known as "narrow angle light scatter" that is
sometimes seen in multicoated optics. This scatter shows as a loss of contrast
and subtle details within bright objects such as Venus, Mars, and Jupiter. It
also shows as a significant difference in the background darkness immediately
surrounding a bright object, which is especially important for double-star
observing. Brandons are accordingly noted for their exceptional contrast and
extremely dark background, two reasons why Questar has been using them in their
ultra-premium Maksutov-Cassegrain scopes since 1971. They have moderately wide
apparent fields of view, of about 45°.

Brandons are threaded for Vernonscope filters only. The use of standard
eyepiece color or nebula filters requires adapter #3405. They have rubber
eyecups that roll down for eyeglass use, although their eye relief is quite
short in the shorter focal lengths. Brandons are the sharpest design currently
available in a 1.25" barrel size for eyepiece projection photography. However
from time to time I do enjoy using the TeleVue plossls as well.

Great post John.