Anyone own a Celestron 11'' schmidt cassegrain?

  • Thread starter Thread starter EIRE2003
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The user is experiencing issues with aligning their Celestron C11 telescope using the auto three-star alignment method. Despite correctly setting the counterweight bar to point north and aligning the eyepiece with Polaris, the telescope incorrectly slews towards the western horizon when selecting Betelgeuse as the first alignment star. There is confusion regarding the initial setup, particularly the orientation of the counterweight and optical tube. Suggestions include verifying time zone settings and ensuring the telescope's position aligns with the expected celestial coordinates. The discussion highlights the importance of proper alignment and understanding the mount's mechanics for successful operation.
EIRE2003
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Hi there,

I am using a celestron C11. But I really need some help with aligning it up through auto 3 star align.

The counter weight bar pointing approximately due north with the index marks aligned and locked.

I aligned the eyepiece with the finderscope on polaris.

I set the exact time and date, longitude and latitude for Dublin where I live.

I then selected auto three star alignment method.

I selected betelgeuse as my first alignment star, and that star was in the south east but when i clicked enter on it the telescope slewed down towards the western horizon.

What am I doing wrong??
 
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As a matter of fact, I do... :biggrin:
www.russsscope.net

However, I'm guessing yours is mounted on a Celestron CG-5 mount? Mine is on an Orion mount. But, maybe I can help...

I don't understand what you mean by this:
The counter weight bar pointing approximately due north with the index marks aligned and locked.
Since the counterweight shaft is the dec axis, it is always perpendicular to the polar axis. The hole through the center of the mount (if you don't have a polar alignment scope in it) should point at Polaris. Usually, the home position has the counerweight shaft pointed down and the scope pointed north (like the picture on the front of the manual).

Other things to check:
-Time Zone
-E vs W longitude
 
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Yes its on a CG-5 mount.
I mean the counter weight bar is pointing down and the optical tube is pointing at polaris. And the index marks (the two pairs of triangles are aligned with each other).
 
Another possibility - Beetlegeuse is due south at sunset right now. Please don't be insulted, but you aren't mixing it up with Procyon, are you (which is in the southeast)?

The telescope and counterweights should be turning roughly parallel to the ground with the scope rotating something like 140 degrees around the dec axis. Is it actually pointed down at the ground or just lower and further south than you think it should?
 
No betelgeuse is the red supergiant star situated diagonally to rigel. And it was in the south when was I trying to align it.

The image I have attached indicates how the scope is aligned initially when pointing at polaris in the north. Is that right?
The tube points to the west on the horizon.
 

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3I/ATLAS, also known as C/2025 N1 (ATLAS) and formerly designated as A11pl3Z, is an iinterstellar comet. It was discovered by the Asteroid Terrestrial-impact Last Alert System (ATLAS) station at Río Hurtado, Chile on 1 July 2025. Note: it was mentioned (as A11pl3Z) by DaveE in a new member's introductory thread. https://www.physicsforums.com/threads/brian-cox-lead-me-here.1081670/post-7274146 https://earthsky.org/space/new-interstellar-object-candidate-heading-toward-the-sun-a11pl3z/ One...

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