Poor guiding with AM5 and OAG

27 views
Skip to first unread message

Jack Bernstein

unread,
Aug 4, 2026, 11:36:42 AM (yesterday) Aug 4
to Open PHD Guiding
I just switched my ~650 mm refractor to an AM5 and have added an OAG with a ASI220mm. I polar aligned it and followed recommendations from both calibration and guiding help. After about 20 min, guiding was lost with multiple star lost, low SNR and mass changed. Attached are my logs. I would appreciate it if someone could glance at them and give me some feedback as to how I can make this better. The debug log is compressed because it was too big.
PHD2_GuideLog_2026-08-03_213337.txt
PHD2_DebugLog_2026-08-03_213337.zip

Nelson Viegas

unread,
Aug 4, 2026, 11:57:01 AM (yesterday) Aug 4
to open-phd...@googlegroups.com
Hi Jack,

I'm no PHD2 expert, but I too guide my 950mm f/7.5 refrator with an OAG. You need to change the guider focal length to match the telescope. You focal length seems to indicate that you were guiding with a very short guide scope before, of about 160mm. Needless to say that that won't work. 😅
One thing to remember: If calibration is done quickly with only 3 or 4 steps, then is most likely you have something off in your PHD2 profile configuration. 

Good luck and clear skies!

Best regards,
Nelson Viegas
GOAAA

Jack Bernstein <jack.be...@gmail.com> escreveu (terça, 4/08/2026 à(s) 16:36):
I just switched my ~650 mm refractor to an AM5 and have added an OAG with a ASI220mm. I polar aligned it and followed recommendations from both calibration and guiding help. After about 20 min, guiding was lost with multiple star lost, low SNR and mass changed. Attached are my logs. I would appreciate it if someone could glance at them and give me some feedback as to how I can make this better. The debug log is compressed because it was too big.

--
You received this message because you are subscribed to the Google Groups "Open PHD Guiding" group.
To unsubscribe from this group and stop receiving emails from it, send an email to open-phd-guidi...@googlegroups.com.
To view this discussion visit https://groups.google.com/d/msgid/open-phd-guiding/4a930f61-ef51-469e-8fd7-7bcc21828df1n%40googlegroups.com.

Bruce Waddington

unread,
Aug 4, 2026, 1:55:01 PM (yesterday) Aug 4
to Open PHD Guiding
Nelson is right, whenever you make a configuration change like this, you must re-run the new profile wizard.  You did that when you first started, now you need to do it again.  Don't try to fix this by chipping away at individual parameters in the Advanced Settings dialog, you will just create a bigger mess.  

ProfileWizard_Entry.jpg

Also, going forward, please upload your logs to our server rather than attaching them to forum messages.


Bruce

Jack Bernstein

unread,
Aug 4, 2026, 3:29:33 PM (yesterday) Aug 4
to open-phd...@googlegroups.com, Open PHD Guiding
Thanks Bruce and Nelson!

Jack M. Bernstein
Sent from my iPhone

On Aug 4, 2026, at 13:55, Bruce Waddington <bw_m...@earthlink.net> wrote:


Nelson is right, whenever you make a configuration change like this, you must re-run the new profile wizard.  You did that when you first started, now you need to do it again.  Don't try to fix this by chipping away at individual parameters in the Advanced Settings dialog, you will just create a bigger mess.  

<ProfileWizard_Entry.jpg>

Also, going forward, please upload your logs to our server rather than attaching them to forum messages.


Bruce


On Tuesday, August 4, 2026 at 8:57:01 AM UTC-7 Nelson Viegas wrote:
Hi Jack,

I'm no PHD2 expert, but I too guide my 950mm f/7.5 refrator with an OAG. You need to change the guider focal length to match the telescope. You focal length seems to indicate that you were guiding with a very short guide scope before, of about 160mm. Needless to say that that won't work. 😅
One thing to remember: If calibration is done quickly with only 3 or 4 steps, then is most likely you have something off in your PHD2 profile configuration. 

Good luck and clear skies!

Best regards,
Nelson Viegas
GOAAA

Jack Bernstein <jack.be...@gmail.com> escreveu (terça, 4/08/2026 à(s) 16:36):
I just switched my ~650 mm refractor to an AM5 and have added an OAG with a ASI220mm. I polar aligned it and followed recommendations from both calibration and guiding help. After about 20 min, guiding was lost with multiple star lost, low SNR and mass changed. Attached are my logs. I would appreciate it if someone could glance at them and give me some feedback as to how I can make this better. The debug log is compressed because it was too big.

--
You received this message because you are subscribed to the Google Groups "Open PHD Guiding" group.
To unsubscribe from this group and stop receiving emails from it, send an email to open-phd-guidi...@googlegroups.com.
To view this discussion visit https://groups.google.com/d/msgid/open-phd-guiding/4a930f61-ef51-469e-8fd7-7bcc21828df1n%40googlegroups.com.

--
You received this message because you are subscribed to a topic in the Google Groups "Open PHD Guiding" group.
To unsubscribe from this topic, visit https://groups.google.com/d/topic/open-phd-guiding/kzKdS5gKjTg/unsubscribe.
To unsubscribe from this group and all its topics, send an email to open-phd-guidi...@googlegroups.com.
To view this discussion visit https://groups.google.com/d/msgid/open-phd-guiding/52e87939-0bae-4b25-9387-486e058282ben%40googlegroups.com.
<ProfileWizard_Entry.jpg>
Reply all
Reply to author
Forward
0 new messages