Struggling with what might be wrong with my PHD2 calibration

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Kevin McQuown

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Nov 14, 2025, 10:15:30 AMNov 14
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I've attached images of everything I discuss below. I believe I have successfully run the "automatic" calibration where I do steps 1 and 2. My first target last night was the Pelican Nebula. It slewed and centered properly, started guiding and seemed to be good for the first few minutes but then went haywire. I noticed this about an 1 hour into the session, so I just stopped guiding in PH2 and started guiding again. I though that fixed it although I was concerned why I would even need to do that. This morning I see that it seemed to hold good guiding until the 1st dither and after that it went haywire again. Eventually it slewed to my 2nd target, the Pacman Nebula. Here guiding was excellent throughout the entire target. It then went to the horsehead Nebula and guiding was off the rails again. I've attached my settings for everything that I think is relevant. Unfortunately all the settings needed aren't all in one place. Here is my system. Guide Scope: Uniguide 32 Guide Camera: ASI220M Main Scope: WO RedCat 91 Main Camera: ASI6200MM Pro Mount: AM5N, (no backlash) Any help would be greatly appreciated.

Bruce Waddington

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Nov 14, 2025, 11:42:05 AMNov 14
to Open PHD Guiding
It looks like you're using a separate guide scope (finder-scope) and guide camera but you have PHD2 connected to a rotator.  That doesn't make any sense.  The rotator is presumably for your main imaging camera and telescope.  So only the main camera is being rotated, not the guide camera.  Assuming what I've described is accurate, re-run the new-profile-wizard and don't include a connection to the rotator.

Regards,
Bruce

Kevin McQuown

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Nov 14, 2025, 11:52:38 AMNov 14
to Open PHD Guiding
Not sure why my formatting was off.  Here is a little easier to read.
I've attached images of everything I discuss below.

I believe I have successfully run the "automatic" calibration where I do steps 1 and 2. My first target last night was the Pelican Nebula. It slewed and centered properly, started guiding and seemed to be good for the first few minutes but then went haywire.

I noticed this about an 1 hour into the session, so I just stopped guiding in PH2 and started guiding again. I thought that fixed it although I was concerned why I would even need to do that. This morning I see that it seemed to hold good guiding until the 1st dither and after that it went haywire again.

Eventually it slewed to my 2nd target, the Pacman Nebula. Here guiding was excellent throughout the entire target. It then went to the horsehead Nebula and guiding was off the rails again.

I've attached my settings for everything that I think is relevant.

Unfortunately all the settings needed aren't all in one place.

Here is my system.
Guide Scope: Uniguide 32
Guide Camera: ASI220M
Main Scope: WO RedCat 91
Main Camera: ASI6200MM Pro
Mount: AM5N, (no backlash) Any help would be greatly appreciated. 

Here is a link to all my images and log files. 

Kevin McQuown

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Nov 14, 2025, 11:53:35 AMNov 14
to Open PHD Guiding
OMG, I'm an IDIOT.  Checking that now.

Kevin McQuown

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Nov 14, 2025, 11:56:14 AMNov 14
to open-phd...@googlegroups.com
Hmm, here is my configuration.
Screenshot 2025-11-14 at 10.55.02 AM.png

Kevin McQuown

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Nov 14, 2025, 11:57:05 AMNov 14
to Open PHD Guiding
I see it.  I have disconnected the rotator completely.

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