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William Optics Visual Accessories

William Optics visual accessories make observing with a refractor more comfortable and versatile. Dura Bright 99% dielectric diagonals come in 1.25", 2" and a 2" SCT-threaded version for bright, comfortable viewing angles.

Erecting prisms, including 90° and 45° 1.25" models and versions for the RedCat WIFD and Cat 61, give a correct, upright image for daytime and terrestrial use. The Binoviewer Complete Package and its 2x Barlow nosepiece let you observe with both eyes.

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$158.00 - $158.00
$158.00
$158.00 - $158.00
$158.00

William Optics 99% Dielectric Dura Bright Diagonal - 2"

WO-D-DIG2D-C-DB
2 in stock

2" Barrel with 90° Viewing Angle 99% Reflectivity Dielectric Coatings 1/12th Wave Precision Polished Mirror 12mm Thick Mirror Substrate for Therma...

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$158.00 - $158.00
$158.00
$158.00 - $158.00
$158.00
$369.00 - $369.00
$369.00
$369.00 - $369.00
$369.00

William Optics Binoviewer Complete Package

WO-E-BINO-P
7 in stock

Includes two 20mm 66° wide-angle eyepieces High-quality BaK4 prisms with full multi-coatings Large 20mm clear prism aperture prevents vignetting I...

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$369.00 - $369.00
$369.00
$369.00 - $369.00
$369.00
$138.00 - $138.00
$138.00
$138.00 - $138.00
$138.00

William Optics 99% Dielectric Dura Bright Diagonal - 1.25"

WO-D-125D-C-DB
1 in stock

1.25" Barrel Diameter 99% Dielectric Coated Mirror 1/12λ Mirror Surface Accuracy 12mm Thick Mirror Substrate 100% Real Carbon Fiber Side Plates ...

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$138.00 - $138.00
$138.00
$138.00 - $138.00
$138.00
$116.00 - $116.00
$116.00
$116.00 - $116.00
$116.00

William Optics 90° Erect Prism - 1.25"

WO-D-EP90-125II
5 in stock

Provides a fully corrected, upright, and non-reversed image Designed for 1.25" focusers and eyepieces 90° viewing angle for comfortable observing ...

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$116.00 - $116.00
$116.00
$116.00 - $116.00
$116.00
$59.00 - $59.00
$59.00
$59.00 - $59.00
$59.00

William Optics 2x Barlow Nosepiece for Binoviewer

WO-E-BINO-B2
6 in stock

Provides 2x magnification Enables binoviewers to reach focus in most telescopes Standard 1.25" nosepiece format Threads directly onto the binoview...

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$59.00 - $59.00
$59.00
$59.00 - $59.00
$59.00
$159.00 - $159.00
$159.00
$159.00 - $159.00
$159.00

William Optics RedCat WIFD Erecting Prism - 1.25"

WO-D-EP90-125-RC51III
1 in stock

Converts Astronomical Telescopes for Terrestrial Viewing 90-Degree Viewing Angle Accepts Standard 1.25" Eyepieces Anti-Reflection Coated BAK7 Pris...

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$159.00 - $159.00
$159.00
$159.00 - $159.00
$159.00
$110.00 - $110.00
$110.00
$110.00 - $110.00
$110.00

William Optics 45° Erecting Prism - 1.25"

WO-D-EP125
6 in stock

Provides a fully corrected image (upright and left-right correct) Comfortable 45° viewing angle for terrestrial observation Fits standard 1.25" fo...

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$110.00 - $110.00
$110.00
$110.00 - $110.00
$110.00
William Optics 1.25" 90° Erect Prism for Cat 61 WIFD
$159.00 - $159.00
$159.00
$159.00 - $159.00
$159.00

William Optics 1.25" 90° Erect Prism for Cat 61 WIFD

WO-D-EP90-125-RC61
1 in stock

Provides a fully corrected, erect image for terrestrial viewing Comfortable 90° viewing angle Standard 1.25" barrel accepts most astronomical eyep...

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$159.00 - $159.00
$159.00
$159.00 - $159.00
$159.00
William Optics 2" 90° Dura Bright Dielectric Diagonal for SCT threaded Scope
$207.00 - $207.00
$207.00
$207.00 - $207.00
$207.00

William Optics 2" 90° Dura Bright Dielectric Diagonal for SCT threaded Scope

WO-D-DIG2D-C-DB-SCT
1 in stock

Enables use of 2-inch eyepieces for wide-field views 90° viewing angle for comfortable observing at the zenith Dura-Bright dielectric coatings for...

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$207.00 - $207.00
$207.00
$207.00 - $207.00
$207.00