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IMPORTANT: Our store is located in Canada. All orders that include products manufactured outside of Canada or USA will be subject to tariffs and duties, regardless of the order value. US customers are responsible for all applicable duties and tariffs, and those will be billed by the carrier, except for the Lacerta upgrade kit, for which we collect them at checkout.
IMPORTANT: Our store is located in Canada. All orders that include products manufactured outside of Canada or USA will be subject to tariffs and duties, regardless of the order value. US customers are responsible for all applicable duties and tariffs, and those will be billed by the carrier, except for the Lacerta upgrade kit, for which we collect them at checkout.

Diagonals

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$43.01 - $43.01
$43.01
$43.01 - $43.01
$43.01

David Astro 90° Diagonal - 1.25"

DAV-DIAG-1.25
Only 5 left!

The 1.25" Mirror Diagonal is a must-have accessory for astronomers, providing a comfortable viewing angle and improved image quality during telesc...

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$43.01 - $43.01
$43.01
$43.01 - $43.01
$43.01
$109.00 - $109.00
$109.00
$109.00 - $109.00
$109.00

David Astro 99% Dielectric Twist-Lock Diagonal - 1.25"

DAV-DIG-TL-1.25
6 in stock

The 1.25" 99% Dielectric Twist-Lock Diagonal is an essential upgrade for astronomers seeking the best in optical performance and convenience. This...

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$109.00 - $109.00
$109.00
$109.00 - $109.00
$109.00
$159.00 - $159.00
$159.00
$159.00 - $159.00
$159.00

David Astro 99% Dielectric Twist-Lock Diagonal - 2"

DAV-DIG-TL-2
Only 5 left!

The 2" 99% Dielectric Twist-Lock Diagonal is an essential upgrade for astronomers seeking the best in optical performance and convenience. This pre...

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$159.00 - $159.00
$159.00
$159.00 - $159.00
$159.00
$149.00 - $149.00
$149.00
$149.00 - $149.00
$149.00

David Astro Penta Prism Diagonal - 1.25"

DAV-PENTA-1.25
Only 4 left!

The David Astro Penta Prism 90-Degree Diagonal is a non inverting non reversing diagonal. It’s particularly suited for use with the David Astro Pre...

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$149.00 - $149.00
$149.00
$149.00 - $149.00
$149.00
$219.99 - $219.99
$219.99
$219.99 - $219.99
$219.99

Explore Scientific 99% Reflective Diagonal -2"

ES-DD02-00CF

The Explore Scientific 2-inch Dielectric-Coated Diagonal Mirror comes complete with 1.25-inch Adapter and dust covers. Solid construction and light...

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$219.99 - $219.99
$219.99
$219.99 - $219.99
$219.99
$589.99 - $589.99
$589.99
$589.99 - $589.99
$589.99

Explore Scientific 99% Reflective Diagonal -3"

ES-DD03-01CF

The Explore Scientific 3-inch Dielectric-Coated Diagonal Mirror comes complete with 2 inch Adapter and dust covers. Solid construction and light we...

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$589.99 - $589.99
$589.99
$589.99 - $589.99
$589.99
Tele Vue 60º Everbrite Diagonal - 1.25" 2
Tele Vue 60º Everbrite Diagonal - 1.25" 1
$369.00 - $369.00
$369.00
$369.00 - $369.00
$369.00

Tele Vue 60º Everbrite Diagonal - 1.25"

TV-DPC-6012

Reflectivity: 99% Everbrite Dielectric Coatings Viewing Angle: 60° Barrel Size: 1.25" Construction: Machined Aluminum Housing Eyepiece Holder: Non...

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$369.00 - $369.00
$369.00
$369.00 - $369.00
$369.00
Tele Vue 90º Enhanced Aluminum Diagonal - 1.25" 1
$216.00 - $216.00
$216.00
$216.00 - $216.00
$216.00

Tele Vue 90º Enhanced Aluminum Diagonal - 1.25"

TV-DSC-0125

Diagonal Type: 90° Mirror (Star) Barrel Size: 1.25" Reflectivity: 96% Eyepiece Holder: Brass Clamp Ring Filter Threads: Yes (1.25") Weight: 5 oz (...

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$216.00 - $216.00
$216.00
$216.00 - $216.00
$216.00
Tele Vue 90º Everbrite Diagonal - 1.25" 1
$325.00 - $325.00
$325.00
$325.00 - $325.00
$325.00

Tele Vue 90º Everbrite Diagonal - 1.25"

TV-DPC-1250

Reflectivity: 99% Dielectric Coating Substrate Material: Pyrex Barrel Size: 1.25" Optical Angle: 90° Eyepiece Holder: Non-marring Brass Clamp Ring...

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$325.00 - $325.00
$325.00
$325.00 - $325.00
$325.00
Tele Vue 90º Everbrite Diagonal 1
$450.00 - $450.00
$450.00
$450.00 - $450.00
$450.00

Tele Vue 90º Everbrite Diagonal - 2"

TV-DDP-8004
1 in stock

Reflectivity: 99% Dielectric Coatings Mirror Substrate: Pyrex Body Construction: CNC-Machined Aluminum Eyepiece Holder: Non-Marring Brass Clamp Ri...

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$450.00 - $450.00
$450.00
$450.00 - $450.00
$450.00
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
$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
$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
$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
$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
3 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
$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