Author Topic: PEC Recording with a CGX mount.  (Read 997 times)

Chaudhari Evans

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PEC Recording with a CGX mount.
« on: December 28, 2017, 12:09:56 AM »
I am using a CGX-L which I guidewith PHDusing Celestrons ASCM drivers. As you probably know it is controlled through the hand controller via USB.

Now I 'used' to use EQmod which I had a fairly good handle on how to record perodic error using that. But with this new to me setup I was wondering if there was and 'good' way to automate the data collection.

Or is the old manual guide while recording for 6 minutes or so still the best?

What about the huge ring gear on the CGX-L is 6 minutes enough?

Thanks in advance



David Felkel

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Re: PEC Recording with a CGX mount.
« Reply #1 on: December 28, 2017, 02:26:17 AM »
Interesting that you ask. I too am beginning to look at this.
I will be using PemPro (version III - Beta required). All is set up and ready. Probably tomorrow night.
PemPro, and the Celestron ASCOM driver for it, seem to want to say that the WormCycle Period is 478.69 seconds, which seem long to me. That would be 7.9782 minutes. I guess i will see what happens when i connect it all together and initialize the process.

I would be curious.... Has anyone actually verified the worm cycle period of the CGX-L ??
I have been searching and searching, but cannot seem to locate a reference, other that the screen information as outlined above. That would be verified during initialization, hopefully tomorrow evening.... (unless i try it tomorrow morning just to see if i can read it....). Now... why wait ?? Because i cannot take the computer out to the observatory when the temp is over about 95 degrees (ambient), and right now, it is over 100..... (It is a MAC BOOK PRO).

olaralal

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Re: PEC Recording with a CGX mount.
« Reply #2 on: December 28, 2017, 04:50:13 AM »
There was a recent thread on using the PECTool with cgx-L - and my main point about it with all celestron mounts including this one is that you may need to guide through the st4 port while you do the training.

In this day and age I really don't think anyone needs to resort to manual guide corrections - for any reason. And it won't be as accurate as guiding.

It's not clear if either of you intend to record with the PECTool - but if you have a way to connect to the st4 port for guiding, then the PECTool is free and effective at recording a number of worm periods, averaging them, and loading them into the mount.

I don't think there is a way to use the PECTool and guide with the ascom driver. But there are ascom drivers for cameras and other devices that connect to the st4 port. So ascom is still possible to use in that sense - but you can't use the actual celestron ascom driver and its pulseguide commands to guide while recording with the pectool.

I hope that makes sense...

Frank

vidysriret

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Re: PEC Recording with a CGX mount.
« Reply #3 on: December 29, 2017, 01:26:12 AM »
Quote
I am using a CGX-L which I guidewith PHDusing Celestrons ASCM drivers. As you probably know it is controlled through the hand controller via USB.

Now I 'used' to use EQmod which I had a fairly good handle on how to record perodic error using that. But with this new to me setup I was wondering if there was and 'good' way to automate the data collection.

Or is the old manual guide while recording for 6 minutes or so still the best?

What about the huge ring gear on the CGX-L is 6 minutes enough?

Thanks in advance


No, the old manual guiding is less reliable and precise than using your guide camera. As for "how long"? the period of your worm. Please see the manual under PEC recording.

As for how, you can just record one revolution of the worm using the routine in the HC, or you can record/average several using software like Pempro or Celestron's freebie Pectool.

What I'd do is just record one cycle with the HC and see if that improves things enough for you.

carmiphypart

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Re: PEC Recording with a CGX mount.
« Reply #4 on: January 08, 2018, 08:41:33 AM »
Quote
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

Kash Dickens

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Re: PEC Recording with a CGX mount.
« Reply #5 on: January 09, 2018, 11:38:53 PM »
I can't speak for the CGX mount. But PEC is a recording of the mechanical variations in your individual mount.
Playing it back helps the control anticipate those variations.
Once recorded, all it needs is to be started after alignment, if desired.

For me, if I don't start mine, I get blobby stars. But when I remember to run it, I get much sharper stars generally.
Since it is a recording of the individual mount, once done, all it should need is to be played back.
So take the time to record it once. Then play that back when you want (If you can remember to start the darned thing).

I usually remember after I have some hours of blobby stars images. About then I wonder why some genius didn't make it automatic.

Lots more here to wade through.

gladinises

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Re: PEC Recording with a CGX mount.
« Reply #6 on: January 10, 2018, 06:29:53 AM »
Quote
<p class="citation">QuotePlease 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 [/quote]

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.

Gregory Station

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Re: PEC Recording with a CGX mount.
« Reply #7 on: January 11, 2018, 12:25:45 PM »
I saw somewhere that a PEC recording 'session' lasts 6 minutes. Now if that is just some arbitrary number I do not know. I have a feeling that it is arbitrary and 'hard coded' into the hand controller.

The ONLY thing I have found so far is that the Worm gear is 144mm. No mention on how many teeth etc.

I have submitted a request for info at the Celestron Web site we will see if even they have a clue!

reaipasjime

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Re: PEC Recording with a CGX mount.
« Reply #8 on: January 11, 2018, 04:27:47 PM »
Quote
I saw somewhere that a PEC recording 'session' lasts 6 minutes. Now if that is just some arbitrary number I do not know. I have a feeling that it is arbitrary and 'hard coded' into the hand controller.

The ONLY thing I have found so far is that the Worm gear is 144mm. No mention on how many teeth etc.

I have submitted a request for info at the Celestron Web site we will see if even they have a clue!

It isn't a matter of ratio's or sizes. PEC records the particular irregularities in the gearing. Then does electronic adjustments during motion by the current sent to the motor for that function.
Last time I studied PEC for my particular mount, it said ~10 minutes for it to record. I believe it took less, but who cares?

Try not to over think it. Just do it, then play it back. (Hopefully you can be more diligent than I about actually remembering to turn it on.)

steviselath

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Re: PEC Recording with a CGX mount.
« Reply #9 on: January 11, 2018, 10:46:18 PM »
LOL I plan to, if the weather ever cooperates.

ceusesugua

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Re: PEC Recording with a CGX mount.
« Reply #10 on: January 13, 2018, 11:42:40 AM »
Quote
LOL I plan to, if the weather ever cooperates.

The weather we can't change...
But if you come across a setting to get the darned PEC to come on by default, or a miracle memory booster (Maybe a frozen boot butt kicking machine?)....
Please share!

arovuzar

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Re: PEC Recording with a CGX mount.
« Reply #11 on: January 18, 2018, 11:42:48 AM »
Well crap I downoladed PECTool and it will not install on my laptop.

Says "PEC Tool is not allowed to run on WinTx"

I tried running it as an admin but same error.

Windows 10 64 bit btw.

Kunjan Blanco

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Re: PEC Recording with a CGX mount.
« Reply #12 on: January 20, 2018, 05:35:57 PM »
Quote
Well crap I downoladed PECTool and it will not install on my laptop.

Says "PEC Tool is not allowed to run on WinTx"

I tried running it as an admin but same error.

Windows 10 64 bit btw.

Try running it in compatibility mode for Windows 7, or Windows 8/8.1.
That is yet another wonderful thing about the software for many mounts and programs.
It's like a rotary phone in a digital world.

It's enough to Tee off the Pope.

unetankem

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Re: PEC Recording with a CGX mount.
« Reply #13 on: January 20, 2018, 06:18:37 PM »
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?

unllamerblood

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Re: PEC Recording with a CGX mount.
« Reply #14 on: January 23, 2018, 01:13:49 PM »
Quote
Quote
Quote
<p class="citation">QuotePlease 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 RodIf 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.