
Rebuilding my CGE Pro
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Rebuilding my CGE Pro
by Benne Piscaer (CN member MensaDei)
Celestron has stopped repairing and selling replacement parts for the CGE Pro for some time now. This former heavy equatorial mount had a payload of approx. 45 kg, more than enough to carry their heaviest telescope. The mount was solidly built and reliable.
My CGE Pro started having pointing and tracking problems after installing the Celestron WLAN SkyPortal module and became completely useless. I found a “clone” of the MC online from Camera Concept in NY and after installation, all seemed to work fine. But as soon as I used the Skyportal module again, the same problems came again: Declination didn't respond correctly and the mount was completely messed up, even a simple polar alignment became impossible.
I loved my CGE Pro, and I had no intention of buying a new CGX-L with tripod or using my CGE Pro as a flower stand or doorstop.
Thus, I started looking online for those who had similar experiences and maybe solutions. Solutions with replacing components with expensive reproductions could lead to the same issues again. And there were no longer HC or MC updates. I found some parts (such as servomotors) could be bought via Cloudy Nights and Camera Concept, but origin and delivery time are often unknown. Moreover the costs to replace the different parts was relatively high.
My search online lead to a website owned by an amateur and long-time Celestron CGE Pro owner, Chad Gray, who had faced the same issues with his CGE Pro. Turns out he did a retrofit of his mount with stepper motors instead of servos and a controller based on the OnStep computer (with Sky Planetarium). Chad is making these sets available to CGE Pro owners who want to give a second life to the mount. He has clearly illustrated the mounting and operation in a series of videos that you can find here.
The package offered consists of two parts: the stepper motors with belt connection, and the computer with cables. Everything fits neatly in 3D printed boxes that replace the original motor cases (the computer is mounted on the side of the electronics pier). Wi-Fi is included.
Instructions are included and very clear, supplemented with YouTube Videos (CGE Pro Onstep Conversion Chad Gray) illustrating everything clearly. The cost of the package is less than the cost of a servo motor clone from Mexico!!
Below are a few pictures of the completed Onstep module and the RA motor cabinet with the stepper motor.
The OnStep software is simple and logical, and in combination with Sky Planetarium software my old CGE Pro has many extras. There is also an ease of use comparable to Celestron's Nexstar.
After the installation, a few more adjustments were needed, which were solved swiftly with Chad. And I got fast answers and assistance. So I just waited for a clear night and “first light” with the retrofitted CGE Pro.
The setup: a Tec 102mm F7 apo with AISAir Plus and the ASI
Visually the result is beautiful, astrophotography requires tracking (tracking alone produces round stars up to about 90 sec.). I did a “3 star alignment” and I think, with the “9 star alignment” a better model and better tracking is possible, without the need for autoguiding.
A first result was M13 (taken without filter):
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- LarryAlvarez, Thomas Ashcraft, B McCandless and 15 others like this
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