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Thanks to you all Love my new CGEM 1100

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#1 blg


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Posted 17 February 2009 - 11:49 PM

:jump: :bow:I want to thank all of those who provide their expertise to these forums. I've been lurking in these forums for two months, primarily to arrive at a decision on what scope to buy. After 20 years of wishing, I got my dream scope. I just retired and this was my wife's retirement gift. I took a jump in the deep end and bought a CGEM 1100. Previously, I wasn't even in the shallow end. I was in the wading pool.

And, I also learned some pretty basic stuff about the new CGEM and mounts in general that helped me get a quick start.

I got my scope a week ago last Friday. I first set it up in the living room to make sure it was in working order and then waited impatiently for clear skies. Finally, Friday night I took it out for first light.

Unfortunately, I could not get a good alignment. It became painfully obvious that I need to study the sky a lot more than I have. I set it up roughly to the celestial pole as many suggested that was all that was necessary to start alignment. I could not get a good alignment, even after 3 calibration stars. I'm sure I misjudged how far off the alignment stars would initially be and I just accepted the closest bright stars. I knew I had a bad alignment when the 3rd calibration star – Sirius, the only alignment star I was confident of -- wasn't even in the finder scope. In retrospect, I'm sure I got at least one star wrong, probably more than one. Nevertheless, I found M42 – who can't find M42 - and had a great time, that is until the clouds unexpectedly rolled in and I called it a night.

So, I studied my star charts and alignment and calibration stars before taking it out again, which I did tonight. I started with a good polar alignment. (I did not use the polar alignment routine.) Using the two-star alignment, I selected alignment stars I reasonable thought I could find. By the third calibration star, I was right on the money. I started my tour and the selected objects were right in the middle of the eyepiece.

Again, thanks a lot for all the contributions you have made that help us novices get going.


#2 Lane



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Posted 18 February 2009 - 12:13 AM

Congrats on the scope - I did not see you mention collimation in your post. Make sure you do a good collimation as soon as you can get under some steady stars and of course allow the scope to adjust to the outside temp before starting this procedure. These scopes are only roughly collimated at the factory and you will see improvement with a precise collimation.

#3 blg


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Posted 19 February 2009 - 07:14 PM

Thanks for the tip. From what I could tell, the collimation looked good with the out of focus stars centered. Will check more carefully whan I have more time and it's warmer outside.


#4 Dave H.

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Posted 19 February 2009 - 11:15 PM

Congratulations on the CGEM 1100 blg, excellent choice!

Good advice on the collimation. If you are new to SCTs and are not familiar with the process, there is much to be learned on the web, just google SCT collimation.

Also it has been my experience that the 11" tubes can take a little time to cool, and I would recommend you should be certain your scope has cooled and equalized before even checking your collimation. Keeping the big 11" tube in my garage helps make equalization much faster than keeping it in the house, although if you decide to keep yours in your living room it would certainly stimulate conversation when you have house guests! :grin:

Enjoy! :jump:

#5 Arizona-Ken


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Posted 22 February 2009 - 11:35 AM

Congratulations on the new scope!

I recently updated my old C8 with the CG5 GOTO mount, and like you, I had initial problems with the alignment. However, you're right with that three star alignment. Once I started using that, I have had no problems with the GOTO working well.

Arizona Ken

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