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50 products

Showing 1 - 24 of 50 products

Enjoy Comfortable, High-Quality Viewing with Telescope Diagonals

Enhance your observing experience with precision Diagonals from Telescopes Canada. Designed to provide a comfortable viewing angle and superior optical performance, diagonals make stargazing easier on the neck while preserving image brightness and clarity. Perfect for both refractors and catadioptric telescopes, they help you observe the Moon, planets, and deep-sky objects with comfort and precision.

Our collection includes mirror and prism diagonals crafted from high-quality, multi-coated optics that deliver bright, true-color images with minimal distortion. Whether you’re upgrading from a stock diagonal or optimizing your setup for astrophotography, these accessories make a noticeable difference in performance and comfort.

Why Choose Diagonals from Telescopes Canada?

Provides a comfortable, natural viewing position
High-quality mirror and prism options for excellent image clarity
Fully multi-coated optics for maximum light transmission
Compatible with most refractors, SCTs, and Maksutovs
Durable construction built for long-term performance

Experience sharper views and effortless comfort during every observing session.

Shop Telescope Diagonals at Telescopes Canada and elevate your stargazing with precision optics and ergonomic design.

Showing 1 - 24 of 50 products

Save $13

William Optics Accessory William Optics Dura Bright Carbon Fiber 2" Dielectric Diagonal with 99 % Reflectivity - D-DIG2D-C-DB

William Optics Accessory William Optics Dura Bright Carbon Fiber 2" Dielectric Diagonal with 99 % Reflectivity - D-DIG2D-C-DB

William Optics William Optics Dura Bright Carbon Fiber 2" Dielectric Diagonal with 99 % Reflectivity - D-DIG2D-C-DB

$248 CAD $261 CAD

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$Svbony Accessory Svbony 1.25" SV188P Dielectric Diagonal for Refractor - F9171B$ $Svbony Accessory Svbony 1.25" SV188P Dielectric Diagonal for Refractor - F9171B$

Svbony Svbony SV188P Dielectric Diagonals for Refractors - F9171

From $49 CAD

More on the way

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William Optics Accessory William Optics 1.25" Dura Bright Dielectric Diagonal with Carbon Fiber Plates, 99 % Reflectivity - D-125D-C-DB

William Optics Accessory William Optics 1.25" Dura Bright Dielectric Diagonal with Carbon Fiber Plates, 99 % Reflectivity - D-125D-C-DB

William Optics William Optics 1.25" Dura Bright Dielectric Diagonal with Carbon Fiber Plates, 99 % Reflectivity - D-125D-C-DB

$181 CAD $190 CAD

In stock

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William Optics Accessory William Optics NEW Super Quality 1.25" 90° Erect Prism - D-EP90-125II

William Optics Accessory William Optics NEW Super Quality 1.25" 90° Erect Prism - D-EP90-125II

William Optics William Optics NEW Super Quality 1.25" 90° Erect Prism - D-EP90-125II

$152 CAD $160 CAD

In stock

Baader Planetarium Accessory Baader Prism Diagonal T-2/90deg 32mm, including 1.25" Eyepiece Holder and 1.25" Nosepiece - 2456005K

Baader Planetarium Accessory Baader Prism Diagonal T-2/90deg 32mm, including 1.25" Eyepiece Holder and 1.25" Nosepiece - 2456005K

Baader Planetarium Baader Prism Diagonal T-2/90deg 32mm, including 1.25" Eyepiece Holder and 1.25" Nosepiece - 2456005K

$198 CAD

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William Optics Accessory William Optics 1.25" RedCat Erecting Prism - Silver Version (for RedCat/WhiteCat 51 only) - D-EP90-125-RC51-SL

William Optics William Optics 1.25" RedCat Erecting Prism - Silver Version (for RedCat/WhiteCat 51 v2 only, not v2.5) - D-EP90-125-RC51-SL

$187 CAD $197 CAD

In stock

$Svbony Accessory Svbony 1.25" 90 Degree Zenith Mirror Diagonal For Refractors - F9171A$

Svbony Svbony 1.25" 90 Degree Zenith Mirror Diagonal For Refractors - F9171A

$33 CAD

In stock

Baader Planetarium Accessory Baader 2" Clicklock Mirror Diagonal (Was numbered MAX-2C) - 2956100

Baader Planetarium Baader 2" Clicklock Mirror Diagonal (Was numbered MAX-2C) - 2956100

$431 CAD

In stock

Antares Accessory Antares 1.25" 90 Degree Mirror Diagonal for 0.965" Telescopes - MSDH

Antares Antares 1.25" 90 Degree Mirror Diagonal for 0.965" Telescopes - MSDH

$55 CAD

In stock

Save $8

William Optics Accessory William Optics 1.25" 45° Erect prism (upright correct image) - D-EP125

William Optics Accessory William Optics 1.25" 45° Erect prism (upright correct image) - D-EP125

William Optics William Optics 1.25" 45° Erect prism (upright correct image) - D-EP125

$144 CAD $152 CAD

In stock

Antares Accessory Antares 2" Diagonal Mirror (Dielectric) with Twist-Lock - 2MD-DTL

Antares Antares 2" Diagonal Mirror (Dielectric) with Twist-Lock - 2MD-DTL

$173 CAD

In stock

Svbony Accessory SV223 Diagonal 90-degree Clicklock 99% Reflective Dielectric Coating - W9180

Svbony Accessory SV223 Diagonal 90-degree Clicklock 99% Reflective Dielectric Coating - W9180

Svbony SV223 Diagonal 90-degree Clicklock 99% Reflective Dielectric Coating - W9180

From $129 CAD

In stock

Save $14

William Optics Accessory William Optics Dura Bright Carbon Fiber 2" Dielectric Diagonal with 99 % Reflectivity Threads for SCT Scopes - D-DIG2D-C-DB-SCT

William Optics Accessory William Optics Dura Bright Carbon Fiber 2" Dielectric Diagonal with 99 % Reflectivity Threads for SCT Scopes - D-DIG2D-C-DB-SCT

William Optics William Optics Dura Bright Carbon Fiber 2" Dielectric Diagonal with 99 % Reflectivity Threads for SCT Scopes - D-DIG2D-C-DB-SCT

$272 CAD $286 CAD

In stock

Antares Accessory Antares 90° 1.25" Correct Image Star Diagonal - EID90

Antares Antares 90° 1.25" Correct Image Star Diagonal - EID90

$82 CAD

In stock

Baader Planetarium Accessory Baader 2" BBHS ® Prism Star Diagonal Prism with 2" ClickLock Clamp - 2456117

Baader Planetarium Accessory Baader 2" BBHS ® Prism Star Diagonal Prism with 2" ClickLock Clamp - 2456117

Baader Planetarium Baader 2" BBHS ® Prism Star Diagonal Prism with 2" ClickLock Clamp - 2456117

$736 CAD

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Antares Accessory Antares 2" Diagonal Mirror (Dielectric) with Twist-Lock and SCT Threads - 2MDS-DTL

Antares Antares 2" Diagonal Mirror (Dielectric) with Twist-Lock and SCT Threads - 2MDS-DTL

$173 CAD

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Antares Accessory Antares 1.25" 45 Degree Prism Diagonal for 0.965" Telescopes - EID45H

Antares Antares 1.25" 45 Degree Prism Diagonal for 0.965" Telescopes - EID45H

$41 CAD

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Baader Planetarium Accessory Baader 2" BBHS Mirror Diagonal with 2" Click-Lock Clamp - 2456115

Baader Planetarium Accessory Baader 2" BBHS Mirror Diagonal with 2" Click-Lock Clamp - 2456115

Baader Planetarium Baader 2" BBHS Mirror Diagonal with 2" Click-Lock Clamp - 2456115

$698 CAD

More on the way

Antares Accessory Antares 2" 90° Dielectric Diagonal - 2MD-D

Antares Antares 2" 90° Dielectric Diagonal - 2MD-D

$159 CAD

In stock

Askar Accessory Askar 2" High Precision Diagonal

Askar Accessory Askar 2" High Precision Diagonal

Askar Askar 2" High Precision Diagonal

$242 CAD

In stock

iOptron Accessory iOptron 1.25" Dielectric Mirror Diagonal - 6231

iOptron iOptron 1.25" Dielectric Mirror Diagonal - 6231

$110 CAD

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$Svbony Accessory SV222 Correct Image Prism Diagonal 45 Degree 1.25-inch Fully Multi-Coated Metal for Refractor Telescope - W9179A$ $Svbony Accessory SV222 Correct Image Prism Diagonal 45 Degree 1.25-inch Fully Multi-Coated Metal for Refractor Telescope - W9179A$

Svbony SV222 Correct Image Prism Diagonal 45 Degree 1.25-inch Fully Multi-Coated Metal for Refractor Telescope - W9179A

$56 CAD

In stock

Antares Accessory Antares 2" Diagonal Mirror (Dielectric) with SCT Threads - 2MDS-D

Antares Antares 2" Diagonal Mirror (Dielectric) with SCT Threads - 2MDS-D

$159 CAD

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Svbony Accessory SvBony SV221 Mirror Diagonal 1.25inch 90 Degree with Brass Compression Rings - W9178A

Svbony SvBony SV221 Mirror Diagonal 1.25inch 90 Degree with Brass Compression Rings - W9178A

$21 CAD

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Every purchase includes ongoing help with product configuration, assembly and setup, and troubleshooting (hardware/software). While manufacturer warranties still govern repairs, replacements and parts, we’ll guide you through diagnostics and assist with warranty claims.

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