Questar Brandon Eyepieces

They use four lenses in an unsymmetrical duplet formulation created by Chester Brandon. They are the choice of professional astronomers world-wide.

They are very sharp at the center (although somewhat less so at the edges) for superb 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 like Venus, Mars, or Jupiter. It also shows as a significant drop in the background darkness immediately surrounding a bright object, which is especially important for double-star observing.

The eyepieces are designed to thread into the diopter tube of Questar telescopes for visual use and into the Questar camera coupling set for eyepiece projection photography, but will also fit into any 1.25” focuser or star diagonal. Their rubber eyecups roll down for eyeglass use, although their eye relief is quite short in the shorter focal lengths.

Questar 8mm Brandon Eyepiece
This is an excellent high power eyepiece (160x and 240x in the 3.5" Questar) for observing lunar and planetary detail, resolving globular clusters, picking up small planetary nebulas against a stellar background, etc.

Questar 12mm Brandon Eyepiece
This is an excellent medium high to high power eyepiece (108x and 162x in the 3.5" Questar) for observing lunar and planetary detail, resolving globular clusters, picking out details in smaller galaxies, etc.

Questar 16mm Brandon Eyepiece
This is an excellent medium power eyepiece (80x and 120x in the 3.5" Questar) for lunar observing, resolving globular clusters, picking up details in the more compact emission and reflection nebulas, etc.

Questar 24mm Brandon Eyepiece
This is an excellent medium to low power eyepiece (53x and 80x in the 3.5" Questar) for lunar observing, resolving globular clusters, viewing the more compact emission and reflections nebulas in their entirety, etc.

Questar 32mm Brandon Eyepiece
This is an excellent low power eyepiece (40x and 60x in the 3.5" Questar) for full views of the Moon, capturing galaxy pairs and compact galaxy clusters, viewing emission and reflection nebulas and smaller open clusters in their entirety, etc.