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Key Features
- Upright, Laterally-Reversed Images
- Fits Catadioptric 2"-18 Rear Threads
- Starbright XLT Coatings
The Celestron 90-Degree Mirror Diagonal (2") is a star diagonal with StarBright XLT coating, for use with Schmidt-Cassegrain telescopes with the 2"-18 threaded device.
More DetailsStar diagonal is the term commonly associated with 90° mirror diagonals such as this, which let you view objects that are at a 90° angle from the direction the telescope is pointing. This allows quite comfortable viewing when the telescope is at or near the zenith (directly overhead), and is fairly comfortable when observing terrestrial imagery as well-albeit a bit unorthodox at first.
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question
What is the clear aperture of the Celestron 2 SCT diagonoal?
The Diameter of the ring is 38mm. However no Aperture.
Date published: 2020-07-18
question
este accesorio Celestron 90 Degree mirror diagonal 2 sirve para el telescopio CPC 1100 XLT 280mm ?
Yes, the 90-Degree Mirror Diagonal 2" for SCT Scopes can be used with the CPC 1100 XLT telescope.
Date published: 2022-06-23
Can I use it with a Alpine Astronomical Baader ...
Can I use it with a Alpine Astronomical Baader Diamond Steeltrack Crayford Focuser for SCTs?
The 90-Degree Mirror Diagonal (2-) for SCT Scopes is not made to slide into a Crayford Focuser but to attach directly to the rear cell of SCT telescopes. The Celestron Dielectric Star Diagonal 2" #93573 comes with two interchangeable adapters which allows to switch between a Schmidt-Cassegrain thread adapter and a 2” barrel adapter that would work in a Crayford Focuser.
Date published: 2022-04-26
question
Does this fit edgeHD 800 sct when visual back is removed?
Yes you can remove the visual back from the edge HD 8 , and the 2 diagonal 93527 will fit perfect.
Date published: 2018-08-27
Will this fit a Celestron NexStar Evolution 6". ...
Will this fit a Celestron NexStar Evolution 6". should I just get the the other 1.25" Dielectric Diagonal(with the orange Twist-lock)
Hi ! This diagonal fits Celestron 6 SCT, BUT thing about 6" OTA is that is it focused on using 1,25 accesuaries. The baffle opening on it's back is only 27mm in diameter, and that's why it is useless to use 2 inch eyepieces for example.
Date published: 2025-08-28
Is this diagonal compatible with the Orion ED80 ...
Is this diagonal compatible with the Orion ED80 80mm f/7.5 apochromatic refractor’s 2” Crawford focuser?
No, the Celestron 90-Degree Mirror Diagonal (2") for SCT Scopes would not be compatible with a refractor like the Orion ED80 80mm f/7.5 Apochromatic Refractor Telescope.
Date published: 2022-11-17
how muck precent light it reflects
how muck precent light it reflects
The 90-Degree XLT mirror diagonal is 95-96% reflectivity.
Date published: 2021-02-02
The Diagonal (2") has 2"-18 threads; will it fit ...
The Diagonal (2") has 2"-18 threads; will it fit the rear cell of the Celestron 8" evolution OTA which has a thread spec of 2"-24?
Yes, the Celestron 90-Degree Mirror Diagonal (2") for SCT Scopes will fit the rear threads of the Celestron NexStar Evolution 8 203mm f/10 Schmidt-Cassegrain GoTo Telescope.
Date published: 2023-06-19