Plate solving changing the hint for image scale


#1

Last night my M51 sequence almost got lost after the meridian flip, due to a bad solve.

I use Pinpoint as the primary solver and a local installation of astrometry.net as the secondary solver. The profile is setup with 2.15 arcsec/pixel. The first successful solve of the night was in astrometry.net and this returned a scale of 2.12 arcsec/pixel. This new value replaced the setting for the sequence. When doing so, the system also changed the setting for the smallest stars to be used in the solve (used by Pinpoint) from 15mag to 20mag. Subsequent solves stayed at these values and everything went good, except Pinpoint was not able to solve anymore.


[17.04.2016 23:22:44] [DEBUG] [Telescope Thread] Plate Solve Hint RA: 13,4939691481826
[17.04.2016 23:22:44] [DEBUG] [Telescope Thread] Plate Solve Hint DEC: 47,2080522017045
[17.04.2016 23:22:44] [DEBUG] [Telescope Thread] Plate Solve Hint Scale: 2,12065954832021
[17.04.2016 23:22:44] [DEBUG] [Telescope Thread] Plate Solve Hint Angle: 356,047163185657
[17.04.2016 23:22:44] [DEBUG] [Telescope Thread] Plate Solve Search: Use up to magnitude 20 stars
[17.04.2016 23:22:44] [DEBUG] [Telescope Thread] Plate solve binning: 1600
[17.04.2016 23:22:44] [DEBUG] [Telescope Thread] Plate solve exp len: 20
[17.04.2016 23:22:48] [DEBUG] [Telescope Thread] Auto center scope frame failed to solve.Solve failed! Failed to solve plate, possibly due to input plate scale being too far off.
[17.04.2016 23:22:48] [DEBUG] [Telescope Thread] Center Here validation frame solve failed, invoking blind failover…
[17.04.2016 23:22:48] [DEBUG] [Telescope Thread] Astrometry.NET: Sequence endpoint data: Astrometry.NET (Remote)
[17.04.2016 23:22:48] [DEBUG] [Telescope Thread] Astrometry.NET: Sequence endpoint data: Astrometry.NET (Remote)
[17.04.2016 23:22:48] [DEBUG] [Telescope Thread] Astrometry.NET: Sequence endpoint data: http://192.168.2.103:8082/api
[17.04.2016 23:22:48] [DEBUG] [Telescope Thread] Astrometry.NET convertedAstrometry.fits path: C:\Users\HCO\AppData\Local\SequenceGenerator\Temp\convertedAstometry.fits
[17.04.2016 23:22:48] [DEBUG] [Telescope Thread] Astrometry.NET - File is too large, resizing
[17.04.2016 23:22:48] [DEBUG] [Telescope Thread] Astrometry.NET - Saving file
[17.04.2016 23:22:48] [DEBUG] [Telescope Thread] Astrometry.NET using endpoint: http://192.168.2.103:8082/api/
[17.04.2016 23:22:48] [DEBUG] [Telescope Thread] Astrometry.NET - Calling Async Solve
[17.04.2016 23:22:49] [DEBUG] [Unknown] Astrometry.NET uploading file: C:\Users\HCO\AppData\Local\SequenceGenerator\Temp\convertedAstometry.fits
[17.04.2016 23:23:09] [DEBUG] [Unknown] Astrometry.NET - Upload complete
[17.04.2016 23:23:09] [DEBUG] [Unknown] Astrometry.NET - Waiting for solve to complete
[17.04.2016 23:23:10] [DEBUG] [Unknown] Astrometry.NET - Job successfully solved
[17.04.2016 23:23:10] [DEBUG] [Unknown] Astrometry.NET solve done in 13 seconds.
[17.04.2016 23:23:10] [DEBUG] [Telescope Thread] Astrometry.NET - Solve Completed
[17.04.2016 23:23:10] [DEBUG] [Telescope Thread] Astrometry.NET - Solve Successful
[17.04.2016 23:23:10] [DEBUG] [Telescope Thread] Astrometry.NET - RA: 13,5835297850667
[17.04.2016 23:23:10] [DEBUG] [Telescope Thread] Astrometry.NET - DEC: 48,8060466124
[17.04.2016 23:23:10] [DEBUG] [Telescope Thread] Astrometry.NET - Scale: 2,12087941551616
[17.04.2016 23:23:10] [DEBUG] [Telescope Thread] Checking to see if solve might be bad…
[17.04.2016 23:23:10] [DEBUG] [Telescope Thread] Solve appears to be good…

Then the meridian flip came. The first solve after the flip returned a new scale of 1.937 arcsec/pix and this got to be the new hint. With this value, neither Pinpoint nor astrometry.net were able to solve the frames anymore and the system got in an endless recovery. Endless due to the wrong value for the image scale.


[18.04.2016 01:36:29] [DEBUG] [Camera Thread] SGM_CAMERA_PLATE_SOLVER_CAPTURE complete…
[18.04.2016 01:36:29] [DEBUG] [Telescope Thread] Plate Solve Hint RA: 13,4938051684944
[18.04.2016 01:36:29] [DEBUG] [Telescope Thread] Plate Solve Hint DEC: 47,1985440340909
[18.04.2016 01:36:29] [DEBUG] [Telescope Thread] Plate Solve Hint Scale: 1,93761895504216
[18.04.2016 01:36:29] [DEBUG] [Telescope Thread] Plate Solve Hint Angle: 55,3542808406799
[18.04.2016 01:36:29] [DEBUG] [Telescope Thread] Plate Solve Search: Use up to magnitude 20 stars
[18.04.2016 01:36:29] [DEBUG] [Telescope Thread] Plate solve binning: 1600
[18.04.2016 01:36:29] [DEBUG] [Telescope Thread] Plate solve exp len: 20
[18.04.2016 01:36:35] [DEBUG] [Telescope Thread] Auto center validation frame failed to solve. Solve failed! Failed to solve plate. Possibly due to a gross mismatch in the number of detected stars versus the number of catalog stars in the area.
[18.04.2016 01:36:35] [DEBUG] [Telescope Thread] Auto center validation frame solve failed, invoking blind failover…
[18.04.2016 01:36:35] [DEBUG] [Telescope Thread] Astrometry.NET: Sequence endpoint data: Astrometry.NET (Remote)
[18.04.2016 01:36:35] [DEBUG] [Telescope Thread] Astrometry.NET: Sequence endpoint data: Astrometry.NET (Remote)
[18.04.2016 01:36:35] [DEBUG] [Telescope Thread] Astrometry.NET: Sequence endpoint data: http://192.168.2.103:8082/api
[18.04.2016 01:36:36] [DEBUG] [Telescope Thread] Astrometry.NET convertedAstrometry.fits path: C:\Users\HCO\AppData\Local\SequenceGenerator\Temp\convertedAstometry.fits
[18.04.2016 01:36:36] [DEBUG] [Telescope Thread] Astrometry.NET - File is too large, resizing
[18.04.2016 01:36:36] [DEBUG] [Telescope Thread] Astrometry.NET - Saving file
[18.04.2016 01:36:36] [DEBUG] [Telescope Thread] Astrometry.NET using endpoint: http://192.168.2.103:8082/api/
[18.04.2016 01:36:36] [DEBUG] [Telescope Thread] Astrometry.NET - Calling Async Solve
[18.04.2016 01:36:36] [DEBUG] [Unknown] Astrometry.NET uploading file: C:\Users\HCO\AppData\Local\SequenceGenerator\Temp\convertedAstometry.fits
[18.04.2016 01:36:44] [DEBUG] [PHD2 Listener Thread] PHD2 - No messages received from PHD2 for 1 minute, checking socket with status…
[18.04.2016 01:36:44] [DEBUG] [PHD2 Listener Thread] Checking PHD2 state…
[18.04.2016 01:36:44] [DEBUG] [PHD2 Listener Thread] PHD2 GetPhdStatus - Pre-Wait : Stopped
[18.04.2016 01:36:44] [DEBUG] [PHD2 Listener Thread] Sending to PHD2:
{“method”: “get_app_state”, “id”: 1001}

[18.04.2016 01:36:44] [DEBUG] [PHD2 Listener Thread] PHD2 GetPhdStatus - Post-Wait: Stopped
[18.04.2016 01:36:59] [DEBUG] [Unknown] Astrometry.NET - Upload complete
[18.04.2016 01:36:59] [DEBUG] [Unknown] Astrometry.NET - Waiting for solve to complete
[18.04.2016 01:36:59] [DEBUG] [Unknown] Astrometry.NET solve done in 22 seconds.
[18.04.2016 01:37:00] [DEBUG] [Telescope Thread] Astrometry.NET - Solve Completed
[18.04.2016 01:37:00] [DEBUG] [Telescope Thread] Astrometry.NET - Failed to solve image.
[18.04.2016 01:37:00] [DEBUG] [Telescope Thread] Auto center validation frame solve failed. Failed to solve image
[18.04.2016 01:37:12] [DEBUG] [Pier Flip Thread] Recovering the sequence (when centering after the meridian flip)
[18.04.2016 01:37:12] [DEBUG] [Pier Flip Thread] Adding sequence level notification: Something has gone wrong when centering after the meridian flip

Fortunately, I was half-awake and, after some time, I managed to understand what happened and could bring the sequence back on track then went to bed. The sequence closed in the morning with a computer crash but this might be due to Windows 10 deciding to get an update during the morning hours.

The complete log is here:

sg_logfile_20160417213743.zip (95.8 KB)

I would like to suggest to let the solve parameter at the values set in the Profile/Control Panel and not try to improve them dynamically. After all, the image scale for a given profile does not change and it should be measured and decided upon by the user outside of the sequence. The way it is now, there is always a risk of a sequence committing suicide due to a bad solve.

Regards,
Horia


#2

@Horia

Thx for the report. We’ll put some thought into this.

Ken


www.mainsequencesoftware.com