Author Topic: PEC Recording with a CGX mount.  (Read 81 times)


  • Active Astronomer
  • ***
  • Posts: 109
  • Activity:
  • Reputation: +0/-0
    • View Profile
Re: PEC Recording with a CGX mount.
« Reply #15 on: January 31, 2018, 01:12:33 PM »

<p class="citation">UlteriorModem, on 25 Aug 2017 - 02:30 AM, said:<a href=";module=forums&amp;section=findpost&amp;pid=8065854" rel="citation">[/url]<blockquote class="ipsBlockquote built" data-author="UlteriorModem" data-cid="8065854" data-time="1503621022">

<p class="citation">Quote
Please see the manual under PEC recording
Well the manual that comes with the CGX and the XLunder PEC states to see the supplement on astro imaging. The supplement is not included.

You have to refer back to the CGE manual which does have the supplement but off course does not have the worm period for the GGX or XL for that matter.

I will look into this PECtool. If I understand correctly you have to get ST4 guiding working first. Right now I am using pulse guiding. Never even tried ST4 with this mount.

But good advice on trying a 'manual' run once and see if it changes anything.

Right now I have been tinkering with the gear mesh and balance on the RA however weather keeps holding me back. As usual. Once I get that narrowed down I will start on PEC.

Thanks for the input so far

Well, ain't that the pits? At any rate, just do the recording using the HC (the instructions can be found in the AVX manual), and how long that takes will give you the worm period of your mount.


Uncle Rod
If you do it according to the HC doesn't the HC tell you when your done? I remember that way, of course, I'm old.[/quote]

Yes, that's what I'm saying...if you use the HC instead of a laptop, the HC will tell you when the recording is done. Start your guide-camera guiding with PHD or whatever, go to the HC and stat the pec recording, and watch for it to prompt you that it is done.

Elijah York

  • Active Astronomer
  • ***
  • Posts: 112
  • Activity:
  • Reputation: +0/-0
    • View Profile
Re: PEC Recording with a CGX mount.
« Reply #16 on: February 09, 2018, 11:02:43 AM »
Thanks ran it in Win7 compatiblity and that worked.

Let me see if I got this straight.

1.) I have to set up guiding through phd2 via the ST4 port?
2.) I do not need an imaging camera running, just the guide camera?

Then just get the program to 'talk' with the hand controller. Start the mount guiding, then start the pectool?

If it's possible for you to guide through the st4 port then I would go ahead and use the pectool since you have it installed.

But if it's a problem setting up st4 guiding then I would do what Rod suggests and just record PEC with the handcontrol - while autoguiding with ascom or whatever you normally use. That will record one worm period and tell you when it's done.

One worm period may be ok but it depends on how the cgx-l is geared. Some mounts have multiple frequencies in the PE graph and you get a big benefit by averaging many. But other mounts don't have that problem and one curve would do pretty well. I haven't seen a multi-period guide curve from cgx-l so I can't tell. CGE's and CGE-Pro's benefit from averaging many curves - which the PECTool can do.

No matter how you record PEC you need to find the worm index first - so be prepared for the mount to warn you that it needs to seek the index - which means moving away in RA for a degree or so.

If you use the hc to record PEC just follow its instructions after finding the index and guiding well on a star.

If you use the PECTool then do the same, and then set it up for batch training with up to 8 periods or so. It will do multiple curves in succession and save them to individual files - then at the end it will ask if you want to average them and load them into the mount. It makes it all very easy.

There is another option that I think would work that lets you use PECTool and averaging - but without needing st4 - but it would be more trouble. You could use the hc to record a curve, then use PECTool to download the curve from the mount and save to file. If you did that several times you could then use PECTool to average them and load them back.

But the simplest of all, which may be perfectly adequate, is just to record one period with the hc and see how well it works.