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CGEM-DX will not guide in dec

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#51 Peter in Reno

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Posted 01 September 2013 - 06:11 PM

+1 what James said.

Celestron mounts are notorious for excessive Dec backlash. I had the same issue with CPC0800 but CGEM as well as other Celestron mounts also have same issue. The best way to minimize Dec backlash issue is to increase PHD Max Dec duration to about 1500-2000msec. This helped me quite a bit but it's not 100% perfect. It's a mechanical issue found in all Celestron mounts. You get what you paid for. I upgraded to Astro-Physics Mach1GTO and Dec backlash was practically eliminated but costs about 4 times more than CGEM.

So, start with PHD Max Dec Duration of about 1500msec. This usually solves Dec backlash issues. Do not set any Dec backlash compensation in CGEM hand controller, leave it at 0.

Peter

#52 Stargazer78

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Posted 01 September 2013 - 06:56 PM

Just got off the phone with James. I am about 95 percent sure I am the error and not the mount! Gonna try again tonight if the clouds break.

#53 Raginar

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Posted 01 September 2013 - 07:26 PM

Orly, I didn't know that! Thanks :)

#54 TimP

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Posted 01 September 2013 - 07:56 PM

Just got off the phone with James. I am about 95 percent sure I am the error and not the mount! Gonna try again tonight if the clouds break.


Did you rule out the cogging issue ? I understand about the up and to the right buttons but that still doesn't address the motor getting hung up when it's tracking.

Tim

#55 Stargazer78

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Posted 01 September 2013 - 08:35 PM

I don't think that's my problem. Starting to think it has been poor polar alignment all this time. I just assumed that was the issue because I believed what my display told me

#56 TimP

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Posted 01 September 2013 - 09:15 PM

I don't think that's my problem. Starting to think it has been poor polar alignment all this time. I just assumed that was the issue because I believed what my display told me


It wouldn't hurt to join Team Celestron. It's free and you can get some good information.

Tim

#57 Bill W.

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Posted 02 September 2013 - 06:25 AM

You definitely have the Dec cogging issue. Go to teamcelestron.com and apply to be a beta tester. You can download the beta firmware and try it. if it doesn't work you can always go back to the original firmware. I have a CGE Pro and had the same issue but it wasn't as severe as you're dealing with.


-Bill

#58 Stargazer78

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Posted 02 September 2013 - 01:47 PM

Well guys I am a little embarrassed here. I do not have the dec cogging issue. I watched a you tube video of that problem and I don't have it. What I do have is operator error! I assumed that my polar alignment was right and in doing so mistook being way off the pole for this dec cogging issue. I want to thank everyone for all your responses. It helped me narrow down my issues..... myself and poor polar alignment!

#59 fetoma

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Posted 02 September 2013 - 02:49 PM

That's cool. This is what we do here to help each other out. Troubleshooting your issues will help someone else's issue down the line. It's what makes these forums an this community so valuable! :grouphug:






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