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CG-5 question

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#1 acav2488

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Posted 15 March 2010 - 05:37 PM

Hi everyone,
I got a new CG-5 a few months ago and I've used it a couple of times and it works great...but, I want to try to improve its tracking accuracy (for AP). So my question is regarding the R.A. calibration feature in the utilities menu. I'm going to have a few days of rain so I just want to know a few things ahead of time before I go trying anything myself. What can you tell me about this feature? i.e. what does is it do for the mount? is it similar to PEC training it?
and what is the procedure for calibrating it? Is this something that I'm going to need a high power reticle eyepiece for? (as of now I cannot use the scope that's on the mount visually, only through a camera viewfinder).
I would just try it inside without an actual alignment but since I'm not sure what this feature does I'm just kind of afraid that I would be giving it a bad (or false?) calibration. Thanks in advance for any info!

#2 Eddgie

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Posted 15 March 2010 - 08:06 PM

If I rememeber correctly, the proceedure for calabrating is to point the scope at a fixed target like a distant terristial object. The process will drive the motor away from the target, then drive it back to the target in RA. If the scope does not go back so the object is dead center again, you use the RA keys to re-center the object. You do the same process for the DEC motor.

This proceedure does not actually do anything for tracking. I think it tries to ensure that the encoders and motor control are in sync. The primary function is to ensure accurate Go-To.

#3 mattyfatz

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Posted 15 March 2010 - 08:22 PM

...This is true, it will only improve accuracy by means of syncing the computer to the drive. Gear ratio's remain the same
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#4 acav2488

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Posted 15 March 2010 - 08:23 PM

Oh OK, thanks Eddgie, that should still be a useful improvement. Do you know of any way(s) to improve tracking accuracy with the cg-5? aside from guiding....maybe something similar to PEC?

#5 acav2488

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Posted 15 March 2010 - 08:29 PM

Thanks Matty,
Any thoughts on ways to improve the tracking?

#6 Erric

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Posted 15 March 2010 - 08:44 PM

Instead of making a new thread, let me ask this:
Can a CG5 track for 5 mins using a small scope (66ED/80ED) without a guider? Like a CGEM/Atlas can?

#7 Gregk

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Posted 16 March 2010 - 09:49 AM

Sometimes I can get 2 minutes with an ED80 at 600mm
Maybe at 200mm you could get 5 minutes

#8 Patrick

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Posted 16 March 2010 - 12:44 PM

Can a CG5 track for 5 mins using a small scope (66ED/80ED) without a guider? Like a CGEM/Atlas can?



No and No. The best I could get consistently with my CG5-GT with an AT66ED (320mm f/l with reducer)was 1 minute. I measured the PE on the CG5 at +/- 20 arc seconds.

I doubt you will be able to go unguided 5 minutes with a CGEM or Atlas either.

Patrick






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