Binoviewer complete package

Binoviewer complete package

Today you can enjoy the benefits of Binoviewer complete package quality binoviewers in your refractor, SCT or Newtonian scope with a convenient PACKAGE including:

-1.25” Binocular style viewer with anti-marring compression rings
-2x William Optics 20 mm WA 66 deg. eyepieces included (available optionally too)
-Barlow nosepiece (1.6x) for easier focusing with most telescopes! It can be mounted on other eyepieces too!
-Exclusive gift box.

Binocular eyepieces usually consist of three or more lens elements in two or more groups. The lens furthest from the viewer’s eye is called the field lens and that closest to the eye the eye lens. The most common configuration is that invented in 1849 by Carl Kellner. In this arrangement, the eye lens is a plano-concave/ double convex achromatic doublet (the flat part of the former facing the eye) and the field lens is a double-convex singlet. A reversed Kellner eyepiece was developed in 1975 and in it the field lens is a double concave/ double convex achromatic doublet and the eye lens is a double convex singlet. The reverse Kellner provides 50% more eye relief and works better with small focal ratios as well as having a slightly wider field.

WO Fit & Finish
• White powder painting.
• Large chromed thumbscrews and anodized aluminum.
• Very useful optional 2x Barlow/Correctors and extenders are available separately for telescopes with special back-focus issues.

BAK4Prisms
• High-quality BAK4 prisms with 20mm clear aperture for maximum brightness and contrast with any telescope.
• Fully Multi Coated.
• Anti-marring brass compression rings for your eyepieces.
• Individual eyepiece focus adjustment.