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Diagonals & Prisms

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  • $129.95 - $129.95
    $129.95
    $129.95 - $129.95
    $129.95

    Astro-Tech 2" 99% Reflectivity Dielectric Mirror Diagonal For Refractors

    Astro-Tech
    In Stock

    This 2” dielectric mirror-type star diagonal is an outstanding value. At this low price, if there ever was a bargain in astronomy, this is it. This...

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    $129.95 - $129.95
    $129.95
    $129.95 - $129.95
    $129.95
  • 1.25" 99% Reflectivity dielectric mirror diagonal
    $79.95 - $79.95
    $79.95
    $79.95 - $79.95
    $79.95

    Astro-Tech 1.25" 99% Reflectivity Dielectric Mirror Diagonal

    Astro-Tech
    In Stock

    This 1.25" Astro-Tech first-surface mirror star diagonal was named a Sky & Telescope Hot Product for 2007! Sky & Tel recognized that the As...

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    $79.95 - $79.95
    $79.95
    $79.95 - $79.95
    $79.95
  • 2" 99% Reflectivity dielectric mirror diagonal for SCTs
    $149.95 - $149.95
    $149.95
    $149.95 - $149.95
    $149.95

    Astro-Tech 2" 99% Reflectivity Dielectric Mirror Diagonal for SCTs

    Astro-Tech
    In Stock

    This 2" dielectric mirror-type star diagonal is designed to give you first-class performance with a Schmidt-Cassegrain - at a money-saving and far ...

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    $149.95 - $149.95
    $149.95
    $149.95 - $149.95
    $149.95
  • $394.00 - $394.00
    $394.00
    $394.00 - $394.00
    $394.00

    TeleVue 2" Everbrite Star Diagonal Package With 2" To 1.25" Adapter

    TeleVue
    In Stock

    This 90° 2” mirror-type star diagonal has Everbrite dielectric mirror coatings for 99% reflectivity. In addition to higher reflectivity than a conv...

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    $394.00 - $394.00
    $394.00
    $394.00 - $394.00
    $394.00
  • 2" Starbright XLT Enhanced aluminum mirror diagonal for SCTs
    $179.95 - $179.95
    $179.95
    $179.95 - $179.95
    $179.95

    Celestron 2" Starbright XLT Enhanced Aluminum Mirror Diagonal for SCTs

    Celestron
    In Stock

    This Celestron 2" mirror star diagonal for catadioptric telescopes has Starbright XLT enhanced aluminum multicoatings for a reflectivity of better ...

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    $179.95 - $179.95
    $179.95
    $179.95 - $179.95
    $179.95
  • 1.25" Prism diagonal
    $43.95 - $43.95
    $43.95
    $43.95 - $43.95
    $43.95

    Celestron 1.25" Prism Diagonal

    Celestron
    In Stock

    A Star Diagonal lets you view objects that are at a 90° angle from the direction the telescope is pointing, thereby allowing comfortable viewing wh...

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    $43.95 - $43.95
    $43.95
    $43.95 - $43.95
    $43.95
  • 1.25" Everbrite 99% Reflectivity mirror diagonal
    $285.00 - $285.00
    $285.00
    $285.00 - $285.00
    $285.00

    TeleVue 1.25" Everbrite 99% Reflectivity Mirror Diagonal

    TeleVue
    In Stock

    This 90° 1.25" mirror-type star diagonal has Everbrite dielectric mirror coatings for 99% reflectivity. In addition to higher reflectivity than a c...

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    $285.00 - $285.00
    $285.00
    $285.00 - $285.00
    $285.00
  • 45° Prism for 1.25" eyepieces
    $51.95 - $51.95
    $51.95
    $51.95 - $51.95
    $51.95

    Celestron 45° Prism for 1.25" Eyepieces

    Celestron
    In Stock

    This 45-degree viewing angle image erecting diagonal is designed to use 1.25" eyepieces in catadioptric scopes with a 1.25" visual back or in refra...

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    $51.95 - $51.95
    $51.95
    $51.95 - $51.95
    $51.95
  • Save $42.50 Save $0.00
    $170.00
    $170.00 - $170.00
    $170.00
    $127.50
    $127.50 - $127.50
    $127.50

    Takahashi 1.25” Prism Diagonal

    Takahashi
    More on the way

    This premium 1.25" Takahashi TAKSD1 compression ring prism star diagonal is the diagonal that Takahashi puts with all of their complete telescope s...

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    $170.00
    $170.00 - $170.00
    $170.00
    $127.50
    $127.50 - $127.50
    $127.50
    Save $42.50 Save $0.00
  • $409.00 - $409.00
    $409.00
    $409.00 - $409.00
    $409.00

    TeleVue Schmidt Cassegrain 2" Everbrite Diagonal Rich Field Kit

    TeleVue
    More on the way

    This kit is designed to allow a premium Tele Vue 2" Everbrite diagonal attach to your SCT. This 90° 2” mirror-type star diagonal has Everbrite diel...

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    $409.00 - $409.00
    $409.00
    $409.00 - $409.00
    $409.00
  • 1.25" Enhanced aluminum 96% reflectivity mirror diagonal
    $189.00 - $189.00
    $189.00
    $189.00 - $189.00
    $189.00

    TeleVue 1.25" Enhanced Aluminum 96% Reflectivity Mirror Diagonal

    TeleVue
    More on the way

    This 90° 1.25" mirror-type star diagonal uses enhanced aluminum mirror coatings for a full 95% reflectivity. The mirror is overcoated with quartz f...

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    $189.00 - $189.00
    $189.00
    $189.00 - $189.00
    $189.00
  • 1/10Th wave accuracy 2" compression ring mirror w/1.25" adapter
    Save $162.50 Save $0.00
    $650.00
    $650.00 - $650.00
    $650.00
    $487.50
    $487.50 - $487.50
    $487.50

    Takahashi 1/10Th Wave Accuracy 2" Compression Ring Diagonal w/ 1.25" Adapter

    Takahashi
    More on the way

    This 2" diagonal uses a telescope-grade elliptical mirror with a guaranteed 1/10th wave surface accuracy for superb high contrast/high detail lunar...

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    $650.00
    $650.00 - $650.00
    $650.00
    $487.50
    $487.50 - $487.50
    $487.50
    Save $162.50 Save $0.00
  • Takahashi 4 Turret 1.25" Eyepiece Holder
    Save $160.00 Save $0.00
    $640.00
    $640.00 - $640.00
    $640.00
    $480.00
    $480.00 - $480.00
    $480.00

    Takahashi 4 Turret 1.25" Eyepiece Holder

    Takahashi
    More on the way

    Looking for a quick way to change magnifications and not use a zoom eyepiece?  This great accessory from Takahashi might be the ticket.A night of o...

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    $640.00
    $640.00 - $640.00
    $640.00
    $480.00
    $480.00 - $480.00
    $480.00
    Save $160.00 Save $0.00
  • $249.95 - $249.95
    $249.95
    $249.95 - $249.95
    $249.95

    Celestron 2" Dielectric Star Diagonal With Twist-Lock

    Celestron
    In Stock

    Enjoy better views through your telescope with this premium diagonal featuring diffraction-limited optics and dielectric coatings Ensure maximum li...

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    $249.95 - $249.95
    $249.95
    $249.95 - $249.95
    $249.95
  • $305.00 - $305.00
    $305.00
    $305.00 - $305.00
    $305.00

    TeleVue 2" Mirror Diagonal With 96% Reflectivity Enhanced Aluminum Coatings And 2" To 1.25" Eyepiece Adapter

    TeleVue
    In Stock

    This 90° 2” mirror-type star diagonal has enhanced aluminum mirror coatings for 96% reflectivity. The mirror is overcoated with quartz for long lif...

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    $305.00 - $305.00
    $305.00
    $305.00 - $305.00
    $305.00
  • Questar 2" Quartz silver mirror for 7" Questars
    $925.00 - $925.00
    $925.00
    $925.00 - $925.00
    $925.00

    Questar 2" Quartz Silver Mirror for 7" Questars

    Questar
    More on the way

    This 2" Questar star diagonal allows the use of 2" eyepieces with the 7" Questar Maksutov. Its 1/20th wave first surface quartz mirror has silver m...

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    $925.00 - $925.00
    $925.00
    $925.00 - $925.00
    $925.00
  • $322.00 - $322.00
    $322.00
    $322.00 - $322.00
    $322.00

    TeleVue 1.25" 99 Percent Reflectivity Everbite Mirror, 60 Degree Viewing

    TeleVue
    More on the way

    This unique 60° viewing angle 1.25" diagonal allows more comfortable extended viewing of objects near the ecliptic (the Moon and planets, among oth...

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    $322.00 - $322.00
    $322.00
    $322.00 - $322.00
    $322.00
  • $79.00 - $79.00
    $79.00
    $79.00 - $79.00
    $79.00

    iOptron Dielectic Star Diagonal

    iOptron
    More on the way

    Use the iOptron 90° Dielectric Star Diagonal to place your head in a comfortable viewing position when your refractor or catadioptric optical tube ...

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    $79.00 - $79.00
    $79.00
    $79.00 - $79.00
    $79.00
  • $395.00 - $395.00
    $395.00
    $395.00 - $395.00
    $395.00

    Questar 1.25" Mirror Diagonal for Brandon Eyepieces on a 3.5" Questar

    Questar
    More on the way

    The Questar #19107 is a mirror-type 90° viewing angle star diagonal for axial viewing with a 3.5" Questar telescope. It connects to the Cassegrain ...

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    $395.00 - $395.00
    $395.00
    $395.00 - $395.00
    $395.00
  • Questar 45°image erecting prism for Questar 3.5" scopes only
    $460.00 - $460.00
    $460.00
    $460.00 - $460.00
    $460.00

    Questar 45° Image Erecting Prism for Questar 3.5" Scopes Only

    Questar
    More on the way

    This premium Questar 45° viewing angle image erecting diagonal fits into the back of any Questar 3.5" scope to provide upright and correctly left-t...

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    $460.00 - $460.00
    $460.00
    $460.00 - $460.00
    $460.00

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