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Diagonals

This is our selection of diagonals. From dielectric mirrors to regular ones. The diagonal is the accessory you need when you own a refractor or a cassegrain telescope. 

 

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SVBONY SV188P Dielectric Diagonal for Refractor 1.25" (F9171B) - Astronomy Plus Save $8.40 Save $0.00
$70.00
$70.00 - $70.00
$70.00
$61.60
$61.60 - $61.60
$61.60

SVBONY SV188P Dielectric Diagonal for Refractor 1.25" (F9171B)

Svbony

SVBONY SV188P Dielectric Diagonal for Refractor 1.25" There are many 1.25" star diagonals on the market. Many of them have a mediocre mirror qualit...

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$70.00
$70.00 - $70.00
$70.00
$61.60
$61.60 - $61.60
$61.60
Save $8.40 Save $0.00
SVBONY SV223 Diagonal 90-degree 2 inch Clicklock (W9180B) - Astronomy Plus
SVBONY SV223 Diagonal 90-degree 2 inch Clicklock (W9180B) - Astronomy Plus Save $21.84 Save $0.00
$182.00
$182.00 - $182.00
$182.00
$160.16
$160.16 - $160.16
$160.16

SVBONY SV223 Diagonal 90-degree 2 inch Clicklock (W9180B)

Svbony

SVBONY SV223 Diagonal 90-degree 2 inch Clicklock SVBONY SV223 2inch 90-degree diagonal comes with a thick, precision, optical flat mirror with an ...

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$182.00
$182.00 - $182.00
$182.00
$160.16
$160.16 - $160.16
$160.16
Save $21.84 Save $0.00
Askar 2" Diagonal (DIAG2) - Astronomy Plus
Askar 2" Diagonal (DIAG2) - Astronomy Plus
$245.00 - $245.00
$245.00
$245.00 - $245.00
$245.00

Askar 2" Diagonal (DIAG2)

Askar

Askar 2" Diagonal The high-quality CNC machined diagonal, with its matte interior coating and gloss oxidized surface, brings a more premium texture...

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$245.00 - $245.00
$245.00
$245.00 - $245.00
$245.00
William Optics 2" Durabright Diagonal for SCT (D-DIG2D-C-DB-SCT) - Astronomy Plus
William Optics 2" Durabright Diagonal for SCT (D-DIG2D-C-DB-SCT) - Astronomy Plus Save $24.80 Save $0.00
$248.00
$248.00 - $248.00
$248.00
$223.20
$223.20 - $223.20
$223.20

William Optics 2" Durabright Diagonal for SCT (D-DIG2D-C-DB-SCT)

William Optics

William Optics 2" Durabright Diagonal for SCT This 90° 2"mirror-type star diagonal has a Dura-Bright 12mm thick mirror and dielectric mirror coatin...

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$248.00
$248.00 - $248.00
$248.00
$223.20
$223.20 - $223.20
$223.20
Save $24.80 Save $0.00
William Optics 2" Durabright Diagonal (D-DIG2D-C-DB) - Astronomy Plus
William Optics 2" Durabright Diagonal (D-DIG2D-C-DB) - Astronomy Plus
Save $22.80 Save $0.00
$228.00
$228.00 - $228.00
$228.00
$205.20
$205.20 - $205.20
$205.20

William Optics 2" Durabright Diagonal (D-DIG2D-C-DB)

William Optics

William Optics 2" Durabright Diagonal This 90° 2"mirror-type star diagonal has a Dura-Bright 12mm thick mirror and dielectric mirror coatings for 9...

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$228.00
$228.00 - $228.00
$228.00
$205.20
$205.20 - $205.20
$205.20
Save $22.80 Save $0.00
Baader 2" Mirror Diagonal with 2" ClickLock (CLDIAG-2) - Astronomy Plus
Baader 2" Mirror Diagonal with 2" ClickLock (CLDIAG-2) - Astronomy Plus
$438.00 - $438.00
$438.00
$438.00 - $438.00
$438.00

Baader 2" Mirror Diagonal with 2" ClickLock (CLDIAG-2)

Baader Planetarium

Baader 2" Mirror Diagonal with 2" ClickLock With their ground-breaking introduction several years ago of the all-dielectric 2" Maxbright star diago...

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$438.00 - $438.00
$438.00
$438.00 - $438.00
$438.00
Celestron 1.25" 45° Erect Image Diagonal (94112-A) - Astronomy Plus
Celestron 1.25" 45° Erect Image Diagonal (94112-A) - Astronomy Plus
$60.00 - $60.00
$60.00
$60.00 - $60.00
$60.00

Celestron 1.25" 45° Erect Image Diagonal (94112-A)

Celestron

Celestron 1.25" 45° Erect Image Diagonal Did you know that most telescopes work well for daytime viewing as well as for astronomy? If you have a re...

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$60.00 - $60.00
$60.00
$60.00 - $60.00
$60.00
$35.00 - $35.00
$35.00
$35.00 - $35.00
$35.00

Astronomy Plus 1.25" Erect Image Prism Diagonal (TA156)

Astronomy Plus

Astronomy Plus 1.25" Erect Image Prism Diagonal  An erect image diagonal corrects the image orientation, making it appear right-side up and cor...

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$35.00 - $35.00
$35.00
$35.00 - $35.00
$35.00
$164.00 - $164.00
$164.00
$164.00 - $164.00
$164.00

Takahashi 1.25" Diagonal Mirror (TKA00547)

Takahashi

Takahashi 1.25" Diagonal Mirror The Takahashi muli-coated 90 degree diagonal is the perfrect complement to Takahashi eyepieces.  This high quality ...

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$164.00 - $164.00
$164.00
$164.00 - $164.00
$164.00
Antares 2" 90° Dielectric Twist-Lock Diagonal (2MD-DTL) - Astronomy Plus
$175.00 - $175.00
$175.00
$175.00 - $175.00
$175.00

Antares 2" 90° Dielectric Twist-Lock Diagonal (2MD-DTL)

Antares

Antares 2" 90° Dielectric Diagonal The Antares 2" 90° Dielectric Twist-Lock Diagonal has multilayer dielectric coating with 99% reflectivity in gre...

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$175.00 - $175.00
$175.00
$175.00 - $175.00
$175.00
Antares 1.25" 45° Erecting Prism Diagonal (EID45) - Astronomy Plus
$42.00 - $42.00
$42.00
$42.00 - $42.00
$42.00

Antares 1.25" 45° Erecting Prism Diagonal (EID45)

Antares

Antares 1.25" 45° Erecting Prism Diagonal EID45 is a 1.25" 45 degree erecting amici prism for terrestrial viewing and is not recommended for high m...

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$42.00 - $42.00
$42.00
$42.00 - $42.00
$42.00
$161.00 - $161.00
$161.00
$161.00 - $161.00
$161.00

Baader Prism Diagonal T-2/90° 32mm (2456005)

Baader Planetarium

Baader Prism Diagonal T-2/90° 32mm High-quality Zenith Prism T-2/90 ° with 32mm Prism Rigid metal body Connection objective side: T-2 internal t...

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$161.00 - $161.00
$161.00
$161.00 - $161.00
$161.00
$198.00 - $198.00
$198.00
$198.00 - $198.00
$198.00

Baader Zenith Prism Diagonal T-2/90 ° with 32mm Prism (2456005K)

Baader Planetarium

Baader Zenith Prism Diagonal T-2/90 ° with 32mm Prism Includes: T-2/32 Diagonal with focusing 1¼" eyepiece clamp (#2458125) and 1¼" nose piece (...

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$198.00 - $198.00
$198.00
$198.00 - $198.00
$198.00
SVBONY Diagonal 1.25 inch 90-degree Clicklock (W9180A) - Astronomy Plus
Save $18.48 Save $0.00
$154.00
$154.00 - $154.00
$154.00
$135.52
$135.52 - $135.52
$135.52

SVBONY Diagonal 1.25 inch 90-degree Clicklock (W9180A)

Svbony

SVBONY Diagonal 1.25 inch 90-degree Clicklock The diagonal comes with a thick, precision, optical flat mirror with an enhanced 99% reflective diel...

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$154.00
$154.00 - $154.00
$154.00
$135.52
$135.52 - $135.52
$135.52
Save $18.48 Save $0.00
William Optics 1.25" DURA BRIGHT Dielectric Diagonal (D-125D-C-DB) - Astronomy Plus
William Optics 1.25" DURA BRIGHT Dielectric Diagonal (D-125D-C-DB) - Astronomy Plus
Save $15.80 Save $0.00
$158.00
$158.00 - $158.00
$158.00
$142.20
$142.20 - $142.20
$142.20

William Optics 1.25" DURA BRIGHT Dielectric Diagonal (D-125D-C-DB)

William Optics

William Optics 1.25" DURA BRIGHT Dielectric Diagonal Introducing New model William Optics Dura-Bright diagonal - a dramatic step forward in the evo...

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$158.00
$158.00 - $158.00
$158.00
$142.20
$142.20 - $142.20
$142.20
Save $15.80 Save $0.00
Celestron 2" Dielectric Star Diagonal with Twist-Lock (93573) - Astronomy Plus
Celestron 2" Dielectric Star Diagonal with Twist-Lock (93573) - Astronomy Plus
$360.00 - $360.00
$360.00
$360.00 - $360.00
$360.00

Celestron 2" Dielectric Star Diagonal with Twist-Lock (93573)

Celestron

Celestron 2" Dielectric Star Diagonal with Twist-Lock Ensure maximum light transmission without loss of optical quality with the Celestron Dielectr...

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$360.00 - $360.00
$360.00
$360.00 - $360.00
$360.00
Celestron 1.25" Star Diagonal (94115-A) - Astronomy Plus
Celestron 1.25" Star Diagonal (94115-A) - Astronomy Plus
$60.00 - $60.00
$60.00
$60.00 - $60.00
$60.00

Celestron 1.25" Star Diagonal (94115-A)

Celestron

Celestron 1.25" Star Diagonal The Celestron 1.25” Star Diagonal slides into the focuser (1.25”) of your refractor or catadioptric telescope and acc...

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$60.00 - $60.00
$60.00
$60.00 - $60.00
$60.00
Baader FlipMirror II Star Diagonal (BFM-II) - Astronomy Plus
Baader FlipMirror II Star Diagonal (BFM-II) - Astronomy Plus
$332.00 - $332.00
$332.00
$332.00 - $332.00
$332.00

Baader FlipMirror II Star Diagonal (BFM-II)

Baader Planetarium

Baader FlipMirror II Star Diagonal Baader-FlipMirror II Star Diagonal (BFM II) with three ports: Straight-through (S52, M48 and T-2 on both sides...

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$332.00 - $332.00
$332.00
$332.00 - $332.00
$332.00
Antares 1.25" 90° Erecting Prism Diagonal (EID90) - Astronomy Plus
$83.00 - $83.00
$83.00
$83.00 - $83.00
$83.00

Antares 1.25" 90° Erecting Prism Diagonal (EID90)

Antares

Antares 1.25" 90° Erecting Prism Diagonal EID90 is a 1.25" 90 degree erecting amici prism for terrestrial viewing and is not recommended for high m...

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$83.00 - $83.00
$83.00
$83.00 - $83.00
$83.00
$196.00 - $196.00
$196.00
$196.00 - $196.00
$196.00

Antares Diagonal, 2",prism, 45 Degree (2EID45)

Antares

Antares Diagonal, 2",prism, 45 Degree 2" 45 degree correct image prism diagonal, precision polished   In the Box 2EID45 is a 45 degree 2" precision...

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$196.00 - $196.00
$196.00
$196.00 - $196.00
$196.00
Save $6.72 Save $0.00
$56.00
$56.00 - $56.00
$56.00
$49.28
$49.28 - $49.28
$49.28

SVBONY 1.25" Right Angle Mirror Diagonal (F9171A)

Svbony

SVBONY SV188 1.25" Right Angle Mirror Diagonal The SV188 mirror diagonal is suitable for refractors, Celestron EQ, Meade Infinity, and similar tel...

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$56.00
$56.00 - $56.00
$56.00
$49.28
$49.28 - $49.28
$49.28
Save $6.72 Save $0.00
SVBONY Diagonal 45 Degree 1.25-inch Fully Multi-Coated (W9179A) - Astronomy Plus
SVBONY Diagonal 45 Degree 1.25-inch Fully Multi-Coated (W9179A) - Astronomy Plus
Save $9.36 Save $0.00
$78.00
$78.00 - $78.00
$78.00
$68.64
$68.64 - $68.64
$68.64

SVBONY Diagonal 45 Degree 1.25-inch Fully Multi-Coated (W9179A)

Svbony

SVBONY Diagonal 45 Degree 1.25-inch Fully Multi-Coated High-quality 45-degree erecting prism with Phase Coatings allows for good contrast and bri...

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$78.00
$78.00 - $78.00
$78.00
$68.64
$68.64 - $68.64
$68.64
Save $9.36 Save $0.00
SVBONY 90 Degree Prism Diagonal 1.25" (W9179B) - Astronomy Plus
SVBONY 90 Degree Prism Diagonal 1.25" (W9179B) - Astronomy Plus
Save $13.44 Save $0.00
$112.00
$112.00 - $112.00
$112.00
$98.56
$98.56 - $98.56
$98.56

SVBONY 90 Degree Prism Diagonal 1.25" (W9179B)

Svbony

SVBONY 90 Degree Prism Diagonal 1.25" High-quality 90-degree erecting prism with anti-reflection coating allows for good contrast and bright imag...

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$112.00
$112.00 - $112.00
$112.00
$98.56
$98.56 - $98.56
$98.56
Save $13.44 Save $0.00
Takahashi 2" Diagonal Mirror with 1.25" adapter (TKA00543) - Astronomy Plus
Takahashi 2" Diagonal Mirror with 1.25" adapter (TKA00543) - Astronomy Plus
$699.00 - $699.00
$699.00
$699.00 - $699.00
$699.00

Takahashi 2" Diagonal Mirror with 1.25" adapter (TKA00543)

Takahashi

Takahashi 2" Diagonal Mirror with 1.25" adapter The Takahashi 2in diagonal is the perfrect complement to Takahashi eyepieces.  This high quality di...

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$699.00 - $699.00
$699.00
$699.00 - $699.00
$699.00
William Optics 90° 1.25" Erect Prism (D-EP90-125II) - Astronomy Plus
William Optics 90° 1.25" Erect Prism (D-EP90-125II) - Astronomy Plus
Save $13.80 Save $0.00
$138.00
$138.00 - $138.00
$138.00
$124.20
$124.20 - $124.20
$124.20

William Optics 90° 1.25" Erect Prism (D-EP90-125II)

William Optics

William Optics 90° 1.25" Erect Prism This 1.25" 90 deg. erecting prism will very happy to be used with that nice premium refractor of yours! Perf...

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$138.00
$138.00 - $138.00
$138.00
$124.20
$124.20 - $124.20
$124.20
Save $13.80 Save $0.00
William Optics 1.25" inch RedCat Erecting Prism - Silver Version (D-EP90-125-RC51-SL) - Astronomy Plus
William Optics 1.25" inch RedCat Erecting Prism - Silver Version (D-EP90-125-RC51-SL) - Astronomy Plus
Save $19.70 Save $0.00
$197.00
$197.00 - $197.00
$197.00
$177.30
$177.30 - $177.30
$177.30

William Optics 1.25" inch RedCat Erecting Prism

William Optics

William Optics 1.25" inch RedCat Erecting Prism High quality erecting prism with Red anodized plate, the complete housing is made by 6061T Alumin...

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$197.00
$197.00 - $197.00
$197.00
$177.30
$177.30 - $177.30
$177.30
Save $19.70 Save $0.00
Tele Vue 2" 90° Everbrite Diagonal (DDP-8004) - Astronomy Plus
$568.00 - $568.00
$568.00
$568.00 - $568.00
$568.00

Tele Vue 2" 90° Everbrite Diagonal (DDP-8004)

Tele Vue

Tele Vue 2" 90° Everbrite Diagonal Whiter and brighter images. Simply put, that is the benefit the Everbrite mirror coating. The Tele Vue 2″ 90° Ev...

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$568.00 - $568.00
$568.00
$568.00 - $568.00
$568.00
Tele Vue 1.25" 90° Everbrite Diagonal (DPC-1250) - Astronomy Plus
$410.00 - $410.00
$410.00
$410.00 - $410.00
$410.00

Tele Vue 1.25" 90° Everbrite Diagonal (DPC-1250)

Tele Vue

Tele Vue 1.25" 90° Everbrite Diagonal Whiter and brighter images. Simply put, that is the benefit the Everbrite mirror coating. The Tele Vue 1.25″ ...

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$410.00 - $410.00
$410.00
$410.00 - $410.00
$410.00
Celestron 1.25” Dielectric Star Diagonal with Twist-Lock (93571) - Astronomy Plus
Celestron 1.25” Dielectric Star Diagonal with Twist-Lock (93571) - Astronomy Plus
$220.00 - $220.00
$220.00
$220.00 - $220.00
$220.00

Celestron 1.25” Dielectric Star Diagonal with Twist-Lock (93571)

Celestron

Celestron 1.25” Dielectric Star Diagonal with Twist-Lock Ensure maximum light transmission without loss of optical quality with the Celestron Diele...

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$220.00 - $220.00
$220.00
$220.00 - $220.00
$220.00
APM 2" Dielectric Star Diagonal with Fast Lock (APM-2-diag-DX-FL) - Astronomy Plus
APM 2" Dielectric Star Diagonal with Fast Lock (APM-2-diag-DX-FL) - Astronomy Plus
$300.00 - $300.00
$300.00
$300.00 - $300.00
$300.00

APM 2" Dielectric Star Diagonal with Fast Lock (APM-2-diag-DX-FL)

APM

APM 2" Dielectric Star Diagonal with Fast Lock With 1/10 wavelength p-v, our star diagonal offers excellent surface accuracy, which results in top ...

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$300.00 - $300.00
$300.00
$300.00 - $300.00
$300.00
Antares 2" 90° Dielectric Diagonal for SCT (2MDS-D) - Astronomy Plus
$161.00 - $161.00
$161.00
$161.00 - $161.00
$161.00

Antares 2" 90° Dielectric Diagonal for SCT (2MDS-D)

Antares

Antares 2" 90° Dielectric Diagonal for SCT 2MDS-D: 2" Mirror Diagonal for Schmidt-Cassegrain thread-on with pressure band retainer and multilayer d...

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$161.00 - $161.00
$161.00
$161.00 - $161.00
$161.00
Save $19.90 Save $0.00
$199.00
$199.00 - $199.00
$199.00
$179.10
$179.10 - $179.10
$179.10

William Optics 1.25" 90° Erect Prism for Cat 61 WIFD (D-EP90-125-RC61)

William Optics

William Optics 1.25" 90° Erect Prism for Cat 61 WIFD Transform your observing experience with this 90° erect-image prism diagonal, ideal for both t...

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$199.00
$199.00 - $199.00
$199.00
$179.10
$179.10 - $179.10
$179.10
Save $19.90 Save $0.00
$22.00 - $22.00
$22.00
$22.00 - $22.00
$22.00

Astronomy Plus 1.25" Mirror Diagonal (TA153)

Astronomy Plus

Astronomy Plus 1.25" Mirror Diagonal  A 1.25" 90-degree diagonal mirror is a key accessory for astronomy, designed to provide a more comfortabl...

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$22.00 - $22.00
$22.00
$22.00 - $22.00
$22.00
$120.00 - $120.00
$120.00
$120.00 - $120.00
$120.00

Astronomy Plus 2'' 99% Reflexivity Mirror Diagonal (TA163)

Astronomy Plus

Astronomy Plus 2'' 99% Reflexivity Mirror Diagonal A 2" 90-degree diagonal mirror is an essential upgrade for astronomers using refractor and S...

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$120.00 - $120.00
$120.00
$120.00 - $120.00
$120.00
$450.00 - $450.00
$450.00
$450.00 - $450.00
$450.00

Baader 2" ClickLock Diagonal Mirror M68 thread (Zeiss) (CLDIAG-2Z)

Baader Planetarium

Baader 2" ClickLock Diagonal Mirror M68 thread (Zeiss) Telescope side with Carl Zeiss M68 thread / optical length = 109 mm Mirror repels UV and IR...

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$450.00 - $450.00
$450.00
$450.00 - $450.00
$450.00
$324.00 - $324.00
$324.00
$324.00 - $324.00
$324.00

Baader T-2 Maxbright® Mirror Diagonal (MAX-1)

Baader Planetarium

Baader T-2 Maxbright® Mirror Diagonal  1¼ "Maxbright Universal Star Diagonal Borosilikat-mirror, 1/10 lambda surface precision dielectric coating ...

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$324.00 - $324.00
$324.00
$324.00 - $324.00
$324.00
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