SGP Pier flip failure (AP1100/APMM pro and SGP)


Michael 'Mikey' Mangieri
 

 

Hey all, I’m having this issue with my AP1100/APCCPro and SGP.  This was posted to the SGP forum, but maybe I’m doing something wrong in APCC that is causing the issue.  Here is the story:

 

Recently I’ve had SGP fail to execute a pier flip and lost two evenings of precious clear skies. I thought I had everything set up correctly, as many nights have worked out great. But alas, maybe not.

 

I have an AP1100GTO mount operating under APCC Pro and SGP 3.2.0.613.

 

I have setup APCC to use meridian limits so that I can have CWUP within the safe zones with Pier side east so that in those cases a pier flip is not necessary. However, when that is not possible (high DECs) the OTA must pier flip.

 

Here is the section of the log that shows the issue (I can send the entire file if needed, but I’m not on a computer where I can do that right now):

 

[11/10/20 00:04:49.099][DEBUG][Sequence Thread][SQ;] Sending commands…

[11/10/20 00:04:49.099][DEBUG][Sequence Thread][SQ;] SetFlatBox: Frame Type is Light

[11/10/20 00:04:49.099][DEBUG][Sequence Thread][SQ;] EventMarker(2) - t:NGC 1514 (0); e:3; f:1; o:

[11/10/20 00:04:49.099][DEBUG][Sequence Thread][SQ;] Checking if Meridian Flip is needed

[11/10/20 00:04:49.101][DEBUG][Sequence Thread][SQ;] Telescope is on the West side of the mount

[11/10/20 00:04:49.105][DEBUG][Sequence Thread][SQ;] Meridian Flip needed, Hour Angle >= Degrees Past To Flip: -13.4899333333333 >= -14.75

[11/10/20 00:04:49.105][DEBUG][Sequence Thread][SQ;] Running blocking meridian flip…

[11/10/20 00:04:49.105][DEBUG][Main Thread][SQ;] Adding sequence level notification: Running automatic pier flip…

[11/10/20 00:04:49.119][DEBUG][Sequence Thread][SQ;] Sending Notification: Status - Running automatic pier flip…

[11/10/20 00:04:49.128][DEBUG][Main Thread][SQ;] Adding sequence level notification: Cannot Run Meridian Flip:

-Telescope must be pointed across the meridian to pier flip.

 

[11/10/20 00:04:49.186][DEBUG][Main Thread][SQ;] Sending Notification: Error - Cannot Run Meridian Flip:

-Telescope must be pointed across the meridian to pier flip.

 

[11/10/20 00:04:49.191][DEBUG][Main Thread][SQ;] Adding sequence level notification: Failed to complete automatic meridian flip, aborting sequence!

[11/10/20 00:04:49.261][DEBUG][Sequence Thread][SQ;] Sending Notification: Error - Failed to complete automatic meridian flip, aborting sequence!

[11/10/20 00:04:54.352][DEBUG][Image History Worker][SQ;] Star detection using min star size of 2px…

[11/10/20 00:04:54.353][DEBUG][Image History Worker][SQ;] Star detection using max star size of 40px…

[11/10/20 00:04:54.471][DEBUG][Image History Worker][SQ;] Find stars took: 6032 ms…

[11/10/20 00:04:54.471][DEBUG][Image History Worker][SQ;] Star list contains 31 stars…

[11/10/20 00:04:54.471][DEBUG][Image History Worker][SQ;] Calculating HFR with sample size: 2

[11/10/20 00:04:54.821][DEBUG][Image History Worker][SQ;] Image analysis (async) END

[11/10/20 00:05:30.303][DEBUG][Main Thread][SQ;] PopulateDataModel: Transferring view to the data model…

[11/10/20 00:05:30.318][DEBUG][MF Update Thread][SQ;] Performing serialize…

[11/10/20 00:05:51.104][DEBUG][Sequence Thread][SQ;] Blocking Pier Flip: Failed to meridian flip, aborting sequence (True)

[11/10/20 00:05:51.104][DEBUG][Sequence Thread][SQ;] Aborting sequence: Failed to meridian flip

[11/10/20 00:05:51.104][DEBUG][Sequence Thread][SQ;] Set sequence abort

 

Basically it has to do with SGP reporting incorrect time to flip when you are East of the meridian but outside the safe zone. This is just like a normal GEM with CW down. It is reporting 0:47 to flip when in fact the object is 1:50 from the meridian. If I click the Set button in SGP to get to the Meridian Flip settings I get the message about this mount not allowing pier flips prior to crossing the meridian and sets the Degrees Past Meridian to 0. Now SGP correctly reports the time to flip as 1:47.

 

My guess is that if I don’t press the Set button and leave SGP with the incorrect time to flip the flip will fail and I will get the error message. If I press the Set button and let SGP set the Degrees Past Meridian to 0 the flip will succeed.

 

 

AND, here is an experiment I ran last night:

 

Selected an object east of the meridian and outside the meridian safe limit. Mount slewed to the object, CW down. Normal. SGP reports meridian flip in 00h47m. The object, however, is ~ 1h50m east of the meridian. APCC and the V2Driver show a meridian delay of 1.1 hrs. I predicted that the flip would fail, and it did. In 47min I immediately got the error message that the flip was aborted and the log shows the error message “Telescope must be pointed across the meridian to pier flip”.

 

Another attempt is made selecting an object (NGC1444) also east of the meridian and also outside the meridian safe limit. Slew and guiding, CW down, normal. SGP reports a meridian flip that is again too early based on the object’s current location. However, this time I click the ‘Set’ button on the telescope dialog to bring up the meridian flip settings in SGP. SGP immediately responds with a warning message: “Your mount does not allow pier flips prior to crossing the meridian and your ‘Degrees

Past Meridian to Flip’ value has automatically been set to 0’” Clicking OK to dismiss the dialog I see that SGP is now reporting the correct time to flip. Allowing the mount to continue it indeed completes the flip and continues with no problem.

 

It seems to me that (maybe) SGP should be setting the ‘Degrees

Past Meridian to Flip’ to 0 automatically. I’m pretty sure even if I set the value to 0, then slew to an eastern object as above, the value gets reset to a non-zero value. Unless I go and click the ‘Set’ button before starting a sequence, flips will fail.

 

Any ideas if this is a real problem or just a SUE (stupid user error).  Sorry for the long post

 

Mikey

_____________________________________

Michael "Mikey" Mangieri

Astronomy and Rocketry stuff at SkyAndRockets  http://skyandrockets.blogspot.com

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