7 replies to this topic

[ghilios]

Hey folks, has anyone successfully done PEC training with CPWI? I've found the instructions in the manual fairly confusing. In particular, it says to connect the auto guider directly to the mount. I typically do my auto guiding via PHD2, so I'm not sure what else I need to do to configure auto guiding with this approach.

 

What steps have you all used or would recommend?

 

Thanks!

[goldtr8]

At the end of the day its actually quite easy.

 

Use your imaging camera as the guide scope connected to PHD do not use an externally mounted guide scope.    Make sure that you set up the correct parameters in PHD for the camera and OTA if you miss this step you will have to do this all over again (ask me how I know).   Then do the calibration.

 

Now make sure the guiding is working in PHD.   

 

Here is the key that you may have missed.   You should only have CPWI running and PHD running.   CPWI must be connected to the scope and be in full control mode.      Now to connect directly to the mount requires an ASCOM driver but this is tricky as you do not choose any of the normal celestron drivers you must pick CPWI.

 

So once aligned and connected and guiding you start the PEC traninng in CPWI and you are good to go.

 

Dillion has some youtubes that I watched and the lights turned on as I could not figure out how to do it either.

 

So my normal setup is CPWI as the control software using StareSense for calibration.   Then I use SharpCap Pro for my EAA efforts with it connected to CPWI this allows it do plate solves and center objects.   I also use Starry Night again connected via CPWI for slewing to objects in my observation lists.

 

I do not have a guider as of yet, however when I do get one I will have it also connected via CPWI as this is supposed to make the calibration in PHD more robust.   Again here I reference Dillion and his youtube videos.

 

I assume what I wrote is clear as mud but if you watch the youtube's it will make sense.

[ghilios]

Ohhhh this makes perfect sense now. The instructions saying "guiding via ST4" is what threw me off. I think I have what I need to try this now, and will post back after I am back at my imaging site to try it out.

 

Thanks!

[StevenBellavia]

Hi,

 

I am replying to this old thread, as I stumbled upon it while doing the PEC training on our observatory's Celestron CGX-L. I suspect this may also be true for the AVX, but not 100% sure.

 

We discovered that you MUST have the ST4 cable plugged-in for the PEC to be successful.  During training, with CPWI, you must have the on-camera selected for the Mount in PHD2 connections, and the ST4 cable connected.  You can also have the Aux Mount as CPWI (ASCOM).

 

One of many frames, before and after PEC training and playback, is attached.  Almost identical results were attained for over an hour for each, before and after the PEC, all 300 seconds, unguided (we used the main telescope and camera during the training as we do not have a guide-scope or guide camera)

 

Steve

 

P.S.  overexposed after the training as I had the wrong gain set on the camera

Attached Thumbnails

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Edited by StevenBellavia, 02 October 2023 - 01:48 PM.

[freestar8n]

Hi,

 

I am replying to this old thread, as I stumbled upon it while doing the PEC training on our observatory's Celestron CGX-L. I suspect this may also be true for the AVX, but not 100% sure.

 

We discovered that you MUST have the ST4 cable plugged-in for the PEC to be successful.  During training, with CPWI, you must have the on-camera selected for the Mount in PHD2 connections, and the ST4 cable connected.  You can also have the Aux Mount as CPWI (ASCOM).

 

One of many frames, before and after PEC training and playback, is attached.  Almost identical results were attained for over an hour for each, before and after the PEC, all 300 seconds, unguided (we used the main telescope and camera during the training as we do not have a guide-scope or guide camera)

 

Steve

 

P.S.  overexposed after the training as I had the wrong gain set on the camera

This is pretty strange to me because I have done PEC training in various ways with cpwi and cgx-l and I never used the st-4 cable.  At a low level all cpwi does is 1) tell the mount to find the pec index and 2)  tell the mount to begin recording guide corrections.  Later it needs to tell the mount to start PEC playback.  So - all this stuff is really happening in the mount itself.

 

If you guide via ascom into the cpwi ascom driver and you see the mount is actually responding and guiding well, then the mount should be able to record those corrections that it's making.

 

So the main things I'd check are 1)  The guiding is actually working well while you are recording and 2)  the pec playback is really happening.

 

It certainly looks like things worked the way you did them - but I think it should also work via ascom pulseguide, without st4.  And PECTool has the advantage of being able to average many runs - if you can get it set up right.

 

Frank

[StevenBellavia]

Hi Frank,

 

I too thought this was strange.

On my EQ6R Pro using EQMOD ASCOM, I only use pulse guiding to record and playback PEC.

 

We had excellent guiding during the first attempt at recording and playback.

But during our series of 300-second, unguided test exposures, there was no improvement at all.

(I will attach that in the next post).

 

This was the guiding during the first attempt with no cable.

 

Attached Thumbnails

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[freestar8n]

One thing I have seen is that CPWI will make it look as if playback is on, but it really isn't.  This mainly happens after hibernate, and if you go into the configuration menu it may show PEC playback as On.  But if you turn it off, then on and close the window - suddenly it seeks the PEC index and then enables PEC playback.

 

So that might be one explanation - somehow PEC playback isn't actually happening after recording the curve with cpwi.

 

I've gotten in the habit of turning it off and on to make sure it is on...

 

Frank

[StevenBellavia]

This is 5 each of the various 300-second , unguided test exposures.

We did 5 to 12 for each case (the PEC training within minutes of each other, same part of the sky) and the none-PEC a month ago), and they all look similar for each case.

 

On page 32 of the instructions (which seem to only exist for the AVX, as they left it out of the CGX-L manual), it says:

 

"4. Plug the autoguider cable into the autoguider port on the mount’s electronics panel"

 

This is the AVX manual, which Celestron tech support instructed me to use, when I mentioned that the CGX-L is missing it.

 

https://s3.amazonaws...VX-Manual-F.pdf

 

This is just our experience so far, so it would be great if other readers of this post would report their findings.

 

Maybe something went wrong, but not much to do except to click "Begin" and make sure guiding is happening, which it was.  We never turned off the mount or anything between the two different methods.  We just added the cable and created a new PHD2 profile with new connections.

 

Steve

Attached Thumbnails

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Edited by StevenBellavia, 02 October 2023 - 07:02 PM.