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Optical Tube Assemblies

Optical tube assemblies, commonly abbreviated by astronomers as OTAs are simply the tube of the telescope where the optics are internally located. OTAs can be helpful in a situation in which an observer has a compatible mount and doesn't want to buy a whole new telescope with a mount included. Optical Tube Assemblies can come in the form of Maksutov-Cassegrain, Astrographs, Reflectors, Refractors, Schmidt-Cassegrains and many others! With the right mounting connections and range of mount and tripod payload, OTAs are a great choice for changing optical type without changing the mount.

15 Item(s)

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  1. Borg - 45 ED II f/5 Astrograph Set (6045 + 7857 + 7885)

    Borg - 45 ED II f/5 Astrograph Set (6045 + 7857 + 7885)

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    FREE SHIPPING
    (48 States)
    Model#: B04561
    $850.00

  2. Borg 50mm F5 Achromat

    Borg - 50mm F5 Achromat

    Mini Borg scopes may be mounted directly with a 1/4"-20 threaded screw into the standard mounting block (left), or in an available finder bracket.

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    (48 States)
    Model#: 6150
    $215.00

  3. Tripod is NOT included!!!!

    Borg - 71FL Fluorite Optical Tube - Astro Visual Set

    Astro Visual set for the Borg 71FL Fluorite Optical Tube.

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    FREE SHIPPING
    (48 States)
    Model#: 6272
    $1,175.00

  4. Borg Series 45 Optical Tube Black

    Borg - Series 45 Optical Tube - Black

    The Borg Series 45 telescopes are based around a 45mm diameter tube and the 42mm/P1 thread used on the popular M42 photographic system.

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    (48 States)
    Model#: 6037
    $335.00

  5. Camera is NOT Included!!!

    Borg - 71FL Fluorite Optical Tube - Basic Set

    Basic set for the Borg 71FL Fluorite Optical Tube.

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    FREE SHIPPING
    (48 States)
    Model#: 6071
    $1,150.00

  6. Camera NOT included!!!

    Borg - 71FL Fluorite Optical Tube - Series 80 Set

    Series 80 set for the Borg 71FL Fluorite Optical Tube.

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    (48 States)
    Model#: 6171
    $1,150.00

  7. Borg - 77 ED II f/4.6 Astrograph Set (2178 + 7150 + 7137 + 7753 + 7835 + 7870)

    Borg - 77 ED II f/4.6 Astrograph Set (2178 + 7150 + 7137 + 7753 + 7835 + 7870)

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    FREE SHIPPING
    (48 States)
    Model#: B07746
    $1,695.00

  8. Borg - 60mm ED f/5.4 (325mm FL) Achromat

    Borg - 60mm ED f/5.4 (325mm FL) Achromat

    Mini Borg scopes may be mounted directly with a 1/4"-20 threaded screw into the standard mounting block (left), or in an available finder bracket.

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    FREE SHIPPING
    (48 States)
    Model#: 6161
    $299.00

  9. Borg - 71FL Fluorite Optical Tube - Fork Mount Set

    Borg - 71FL Fluorite Optical Tube - Fork Mount Set

    Fork mount set for the Borg 71FL Fluorite Optical Tube.

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    (48 States)
    Model#: 0271
    $1,450.00

  10.  Borg - 77 ED II f/4.3 Astrograph Set (2178 + 7135 + 7835 + 7704)

    Borg - 77 ED II f/4.3 Astrograph Set (2178 + 7135 + 7835 + 7704)

    • BORG 77EDII OTA
    • 0.65x reducer
    • Total of 6 elements
    • 330mm focal length
    • F4.3
    • 35mm full-frame coverage
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    FREE SHIPPING
    (48 States)
    Model#: B07743
    $2,175.00

  11. Borg - Mini Borg 45EDII F7.2

    Borg - Mini Borg 45EDII F7.2

    Mini Borg scopes are compatible with a wide variety of standard Borg back-end accessories:

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    FREE SHIPPING
    (48 States)
    Model#: 6045
    $375.00

  12. Camera is NOT Included!!!!!

    Borg - 71FL Fluorite Optical Tube - Telephoto Set

    Telephoto set for the Borg 71FL Fluorite Optical Tube.

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    FREE SHIPPING
    (48 States)
    Model#: 6271
    $1,195.00

  13. Borg Series 45 Optical Tube - White

    Borg - Series 45 Optical Tube - White

    The Borg Series 45 telescopes are based around a 45mm diameter tube and the 42mm/P1 thread used on the popular M42 photographic system.

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    FREE SHIPPING
    (48 States)
    Model#: 6036
    $315.00

  14. Borg - 60mm ED f/5.8 (350mm FL) Optical Tube

    Borg - 60mm ED f/5.8 (350mm FL) Optical Tube

    Mini Borg scopes may be mounted directly with a 1/4"-20 threaded screw into the standard mounting block (left), or in an available finder bracket.

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    FREE SHIPPING
    (48 States)
    Model#: 6260
    $575.00

  15. Borg - 71FL Fluorite Optical Tube - Fork Mount Set with Tripod

    Borg - 71FL Fluorite Optical Tube - Fork Mount Set with Tripod

    Fork mount set for the Borg 71FL Fluorite Optical Tube with Tripod.

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    FREE SHIPPING
    (48 States)
    Model#: 0271S
    $1,730.00

15 Item(s)

per page

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