David's Astronomy Pages Notes - Session 741 (2020-01-17)

Notes (S740)

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Notes (S742)

	Part A (T Point Mapping)
	Session Aims & Highlights
	- Night Summary Plot  - Session Event Log
	Part B (Imaging)
	Session Aims & Highlights
	- Observing Result  - Night Summary Plot  - Session Event Log
	Operational Issues
	- Critical Issues (0),  Major Issues (1),  Minor Issues (3),  Continuous Improvement (5)
	TPoint Mapping Run
	Images from 2020-01-17  >>

Session Aims & Highlights (2020-01-17)

Main aims

1. TPoint Model. Conduct a mapping run (100+ points) for building a new TPoint Model
2. Targets: Acquire images of selected variable and nearby stars (conditions too light for deep sky imaging) if conditions allowed

Equipment & Software

• 12" LX200 and ST-10XME
• 80mm APO and ZWO ASI 178MC
• CCDApp2, TheSky6, CCDSoft5, PHD2,  POTH Hub
• Pegasus UPB & Motor Focus, TCF-S
• SharpCap 3.2, PHD2  2.6.6dev3
   
• AstroMain 3.19.5 ,  Astroguard 1.2.9,   AstroPlan 1.13.9,  AstroShCap 1.2.10, AstroVOE 1.3.4, UPB 1.4.17  (AstroWeather 1.8.2, AstroAllSky 3.5.1)
  

Highlights

• TPoint Mapping.  TPoint Mapping run was successfully made and a new TPoint created.  New model used in imagimng session, good results.  Slew errors all < 5 arc min, mostly < 3 arc min.

Lowlights

•   Targets.  Wind and Seeing Conditions didn't allow an targets to be observed or imaged

Summary Plots & Logs

Part A) 2019-01-14, TPoint Mapping Session

Sky Conditions (Locate Frames) 2020-01-14

Night Sky Summary Plot,  2020-01-14 Top axis: Sky Brightness at Zenith (in ADU/s) Lefthand axis: Local Time (hh LT). Righthand axis: Sun Altitude (degs)

Pre-Session Weather Forecast (API data from darksky.net), 2020-01-14 Forecast showed  85-95% cloud cover clearing around 03:00 with strong winds (20-26 mph) In the event skies were clear the whole night but winds were strong throughout the night, peaking at around 02:00 Conditions were too windy for quality imaging and the observatory was operated for 3 hour period between 21:45 and 00:55 for a TPoint Mapping Run.

Session Event Log

Time     Event Detail 21:43:23 Session Created Live Session Created (2020-01-14 S00741, ImageSaveNum: 741001) 21:43:37   Scope Switched On Telescope Power has been switched on via UPB Powerbox. 21:45:19   Obs.Manager Started Obs.Manager started 21:45:21   Obs.Overseer Started Obs.Overseer started 21:45:26   Services Started Observatory Services started 21:46:20   Shutter Opened Shutter opened (opening time 44s) 21:46:35   Camera1 Connected SBIG Camera Connected (set point -20°C) 21:46:40   Telescope Connected Telescope Connected (TheSky6) 22:05:33       Focusing Started-Foc1 Foc1 Focusing Started (TCF-S) 22:11:26       Focusing Completed Foc1 AutoFocus Completed (Profile No 1) 00:56:02   Services Stopped Night Services stopped 00:57:15   Services Stopped Observatory Services stopped

Part B) 2019-01-17, Imaging Session

Observing Plan

Observing Result

Dome Slewing Performance

Slew/Centering Performance

Sky Conditions (Locate Frames)

Night Sky Summary Plot Top axis: Sky Brightness at Zenith (in ADU/s) Lefthand axis: Local Time (hh LT). Righthand axis: Sun Altitude (degs)

Pre-Session Weather Forecast (API data from darksky.net) Forecast showed  85-95% cloud cover clearing around 03:00 with strong winds (20-26 mph) In the event skies were clear the whole night but winds were strong throughout the night, peaking at around 02:00 Conditions were too windy for quality imaging and the observatory was operated for 3 hour period between 21:45 and 00:55 for a TPoint Mapping Run.

Session Event Log

Time     Event Detail 00:21:21 Session Created Live Session Created (2020-01-17 S00741, ImageSaveNum: 741001) 00:22:18   Scope Switched On Telescope Power has been switched on via UPB Powerbox. 00:23:58   Services Started Observatory Services started 00:24:08   Telescope Connected Telescope Connected (TheSky6) 00:24:34   Camera1 Connected SBIG Camera Connected (set point -20°C) 00:26:24   Shutter Opened Shutter opened (opening time 45s) 00:36:24 Observatory (Auto) Observatory placed in Fully-Automated Mode 00:36:25 Session Pending Session pending (2020-01-17) 00:36:27 Session Initiating Session initiating (2020-01-17) 00:36:29   Plan Requested Observing Plan requested from AstroPlan (1.13.10) 00:37:15   Plan Loaded Observing Plan loaded to queue (2020-01-17 V1 BEST PLAN, Plan ID: 454) 00:37:19   Camera1 Connected SBIG Camera Connected (set point -20°C) 00:37:23   Telescope Connected Telescope Connected (TheSky6) 00:37:36 Session Equilibration Session ready for dome & camera equilibration 00:37:39   Equilibration Started Dome Equilibration started 00:37:41   Equilibration Skipped Dome Equilibration skipped by user 00:37:43 Session Running Session running 00:37:45   Queue Started Observing Queue started (30 targets selected) 00:38:20       Focusing Started-Foc1 Foc1 Focusing Started (TCF-S) 00:40:19       Focusing Completed Foc1 AutoFocus Completed (Profile No 1) 00:40:22       Focusing Started Foc2 Focusing Started (Secondary Scope, using ShCap) 00:41:38       Focusing Failed Foc2 Focusing Failed - star lost 00:42:25     Target Started (1/30) Target started (1/30, GCVS CM Tau) 00:44:04       Focusing Started-Foc1 Foc1 Focusing Started (TCF-S) 00:46:11       Focusing Completed Foc1 AutoFocus Completed (Profile No 3) 00:59:49     Target Completed Target completed (1/30, GCVS CM Tau) 00:59:51     Target Started (2/31) Target started (2/31, NGC 4222) 01:18:31     Target Completed Target completed (2/31, NGC 4222) 01:18:33     Target Missed (3/31) Target's time slot was missed (3/31, GCVS U Mon) 01:18:35     Target Started (4/31) Target started (4/31, C/2017 T2 (PanStarrs)) 01:20:47       Focusing Started-Foc1 Foc1 Focusing Started (TCF-S) 01:22:36       Focusing Completed Foc1 AutoFocus Completed (Profile No 4) 01:30:23     Target Completed Target completed (4/31, C/2017 T2 (PanStarrs)) 01:30:25     Target Started (5/31) Target started (5/31, GCVS GK Per) 01:32:31       Focusing Failed Foc1 Focusing Failed - star is too dim (TCF-S) 01:35:27     Target Completed Target completed (5/31, GCVS GK Per) 01:36:04     Target Started (6/31) Target started (6/31, GCVS SY Cnc) 01:39:00       Focusing Started-Foc1 Foc1 Focusing Started (TCF-S) 01:40:32   SoftSuspend Called Soft Suspend is called due to Deteriorating Conditions (too few stars) 01:41:10       Focusing Completed Foc1 AutoFocus Completed (Profile No 5) 01:44:03     Target Completed Target completed (6/31, GCVS SY Cnc) 01:44:05   Queue Paused Queue paused for SoftSuspend 01:44:08 Session Suspended Session suspended 01:44:58   Shutter Closed Shutter closed (closing time 49s) 01:54:32     Target Cancelled Target cancelled (7/31, GCVS AM CVn) due to wind 02:04:42     Target Cancelled Target cancelled (8/31, GCVS SU Tau) due to wind 02:15:31     Target Cancelled Target cancelled (9/31, GCVS RR Tau) due to cloud 02:24:27     Target Cancelled Target cancelled (10/31, GCVS FU Ori) due to cloud 02:33:24     Target Cancelled Target cancelled (11/31, GCVS U Gem) due to cloud 02:43:27     Target Cancelled Target cancelled (12/31, GCVS ER UMa) due to wind 02:54:45     Target Cancelled Target cancelled (13/31, GCVS RZ LMi) due to wind 03:06:33     Target Cancelled Target cancelled (14/31, GCVS RZ LMi) due to wind 03:18:29     Target Cancelled Target cancelled (15/31, 38P/Stephan-Oterma) due to wind 03:27:25     Target Cancelled Target cancelled (16/31, GCVS R CrB) due to wind 03:38:21     Target Cancelled Target cancelled (17/31, GCVS U Her) due to wind 03:49:02     Target Cancelled Target cancelled (18/31, GCVS AM Her) due to other condition 03:59:43     Target Cancelled Target cancelled (19/31, GCVS AM Her) due to wind 04:13:17     Target Cancelled Target cancelled (20/31, GCVS S Cyg) due to other condition 04:19:47 Session Resuming Session resuming 04:20:32   Shutter Opened Shutter opened (opening time 45s) 04:20:35 Session Running Session running 04:20:37   Queue Resumed Observing Queue resumed 04:20:39     Target Started (21/31) Target started (21/31, GCVS DY Per) 04:27:18   SoftSuspend Called Soft Suspend is called due to Deteriorating Conditions (too few stars) 04:27:44     Target Completed Target completed (21/31, GCVS DY Per) 04:27:46   Queue Paused Queue paused for SoftSuspend 04:27:48 Session Suspended Session suspended 04:28:38   Shutter Closed Shutter closed (closing time 49s) 04:34:13     Target Cancelled Target cancelled (22/31, GCVS U Gem) due to other condition 04:44:16     Target Cancelled Target cancelled (23/31, GCVS ER UMa) due to wind 04:55:34     Target Cancelled Target cancelled (24/31, GCVS RZ LMi) due to wind 05:07:22     Target Cancelled Target cancelled (25/31, GCVS RZ LMi) due to wind 05:17:28     Target Cancelled Target cancelled (26/31, GCVS SS Her) due to wind 05:27:06     Target Cancelled Target cancelled (27/31, GCVS CY Lyr) due to other condition 05:36:34     Target Cancelled Target cancelled (28/31, GCVS CI Cyg) due to cloud 05:51:45     Target Cancelled Target cancelled (29/31, GCVS SS Cyg) due to wind 06:01:18     Target Cancelled Target cancelled (30/31, GCVS BL Lac) due to wind 06:20:52     Target Cancelled Target cancelled (31/31, GCVS Z And) due to wind 06:20:57   Queue Completed Job Queue completed 06:21:03 Session Continuing Session continuing 06:21:13   Plan Requested Observing Plan requested from AstroPlan (1.13.10) 06:21:23   Plan Loaded Observing Plan loaded to queue (2020-01-17 V2 BEST PLAN, Plan ID: 455) 06:22:13 Wait on Weather Waiting for acceptable weather conditions 06:22:16 Session Suspended Session suspended 06:22:18   Shutter Closed Shutter already closed (closed at 04:28, closing time 49s) 06:22:20   Queue Started Observing Queue started (3 targets selected) 06:30:14 Session Resuming Session resuming 06:30:59   Shutter Opened Shutter opened (opening time 45s) 06:31:02 Session Running Session running 06:31:04   Queue Resumed Observing Queue resumed 06:31:06     Target Started (1/3) Target started (1/3, 38P/Stephan-Oterma) 06:34:13       Focusing Started-Foc1 Foc1 Focusing Started (TCF-S) 06:36:15       Focusing Completed Foc1 AutoFocus Completed (Profile No 6) 06:40:32     Target Completed Target completed (1/3, 38P/Stephan-Oterma) 06:40:34     Target Started (2/3) Target started (2/3, GCVS R CrB) 06:42:03       Focusing Started-Foc1 Foc1 Focusing Started (TCF-S) 06:43:42       Focusing Completed Foc1 AutoFocus Completed (Profile No 7) 06:46:32     Target Completed Target completed (2/3, GCVS R CrB) 06:46:50     Target Started (3/3) Target started (3/3, GCVS U Her) 06:49:03       Focusing Started-Foc1 Foc1 Focusing Started (TCF-S) 06:50:51       Focusing Completed Foc1 AutoFocus Completed (Profile No 8) 06:58:29     Target Completed Target completed (3/3, GCVS U Her) 06:58:32   Queue Completed Job Queue completed 06:58:36 Session Closing Session closing 06:59:31   Shutter Closed Shutter closed (closing time 50s) 07:00:02   Dome Parked Dome parked (parking time 30s) 07:00:15   Telescope Parked Telescope parked (parking time 10s) 07:00:46   Scope Switched Off Telescope Power has been switched off via UPB Powerbox. 07:01:33   Services Stopped Night Services stopped 07:01:35 Session Housekeeping Housekeeping Started (Cleanup FITS, Create Fits Summary, Transfer Files) 07:01:43 Session Finished Session Finished

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Operational Issues (2020-01-14 & 17, S741)

• Critical Issues (0)
• Major Issues (1)
• Minor Issues (3)
• Continuous Improvement (5)

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Critical Issues

• None

Major Issues

• Problems with TCF-S Focuser Driver locking up, causing problems to AstroMain, and to the Computer. This occurred twice in the 48 hours prior to session though wasn't an issue during the session itself.  Unable to find a cause or a solution. Update 2020-01-20: the problem seems to have now gone away.   A backdoor button/facility 'Restart TCF-S Service' has been added to More/Backdoor tab to restart TCF Service if/when the issue arises
   Closed 2H 2020 (AstroMain).

Minor Issues

• Guiding wasn't active during session. Principal reason was the 'Settle Guiding Whilst Focusing' checkbox wasn't checked and b) JobQueue/Guiding routines didn't revert to 'old guiding processes'  . Part fixed by setting 'Settle Guiding Whilst Focusing' checkbox to checked in the Design (ie default setting when program starts)
  Part Fixed, 2020-01-20 (AstroMain 3.19.6)
   
• AstroGuard program hung (stopped responding) whilst Stopping Observatory Services. Program hung after stopping POTH.Telescope (which was in a powered off state) and before Stopping Scorecard. Similar problem has been seen several times before.  Fixed attempted:
  Fixed  2020-01-21 (AstroGuard  1.2.11)
   
• AstroGuard program automatically starts Observatory Services within seconds of manually stopping Services, giving little time to close the program. A delay of ~1 minutes needs to be added to the manager checking process.   Fixed attempted.
  Fixed  2020-01-21 (AstroGuard  1.2.11)

Continuous Improvement

• Add Telescope/Dome Slews associated with Mapping onto the Dome/Scope Chart
  Done  2020-05-19 (AstroMain  3.22.3)
   
• Query: How long does it take to perform Sync followed by short mapping run.  
  S741: Start 00:27:24, End 00:35:00.  Duration 7.5 mins
  S742: Start 20:20:12, End 20:29:00.  Duration 9.5 mins
  Closed.  Answer is 7.5 to 9.5 mins
    
• Create routine that can automate the sync of scope followed by short mapping run 
  Done Apr 2021 (AstroMain)
   
• Weather/Condition charts should ignore data associated with OTA readings that are 'stuck' on a constant value.  Confirmed to have been implemented (2021-05-26).
  Done  (AstroWeather)
   
• Mapping Runs to automatically create a file of points that failed to map allowing points to be re-run/infilled .   Eventually implemented in AstroMain 3.40.2 (2021-05-29). Failed and not completed Map Points are written to file "C:\Data\CCD Imaging\Targets\_Mapping\FailedMapPoints.dat". These can be called up for rerunning using new  'Use FailedMapPoints file' button facility.   Map Point names are carried throughto failed map points file permitting later auditing.
  Done  2021-05-28 (AstroMain 3.40.2)

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TPoint Mapping Run (2020-01-14)

With bright moonlit skies and poor seeing/wind oppportunity was taken to renew the LX200 mount's TPoint Model

155 points were successfully mapped across the sky area that can be accessed by the scope (this is the majority of the sky apart from a circular region having a Declination exceeding 68 degrees above which the camera would collide with the fork base)..  This comprise an initial set of 14 points, a main run of 103 points and then a series of infills (38 points).   In the main run 103 points were successfully mapped out of 123 points attempted (ie rejection rate of 16%)

Without a TPoint Model the Sky RMS Error of the 155 mapped points is 1258 arc sec (21 arc mins).

This is much larger than for the last mapping run made in May 2018 which had a Sky RMS Error of 410 arc secs (6.8 arc mins).  
This would seem to be due to a poorer polar alignment at the time of the new data.

New Mapping Run - 155  data points Scatter Plot. No Terms Modelled		Earlier Mapping Run - 121 data points (2018-05-17) Scatter Plot . No Terms Modelled

The 'best' TPoint Model for the new mapping run incorporates 16 terms (6 equatorial terms, Tube Flexure TX, ACES, ECEC and 6 harmonic terms) and reduces Sky RMS error down to 39 arc secs (0.65 arc mins).    [One data point was dropped from the dataset used for the final TPoint Modelling, 4 data points remain as outliers]

This is a slightly better result than for the last mapping run made in May 2018 which had a Sky RMS Error that reduced down to only 47 arc secs (0.8 arc mins).

With 16 terms the Sky RMS error from the 2018 Mapping fell back from 47 arc secs to 54 arc secs.  If the same 12 terms used for 2018 Model are used for the new TPoint Model the Sky RMS reduces to only 120 arc secs (2.0 arc mins) showing the benefit of extra terms for the new model.  The new model shows a distinct irmprovement when a Fork Flexure term is used which wasn't the case in the old model. It's hard to imagine that the scope's Fork Flexure would have changed but the modelling suggests it has !.

New Mapping Run - 155 data points Scatter Plot with Best Determined TPoint Model  - 16 terms (6 equatorial terms, Fork Flexure, Tube Flexure(tan), ACES, ECEC & 6 harmonic terms)		Earlier Mapping - 121 data points (2018-05-17) Scatter Plot with Best Determined TPoint Model  - 12 terms (6 equatorial terms, Tube Flexure(tan), ACES, ECEC & 3 harmonic terms)

Although overall improvements to Polar Alignment were believed to have been made during measurements and adjustments in Dec 2019 (after worsening between May 2018 and Nov 2019) and the data suggests that the azimuthal error (1.4 arc mins) is indeed improved the mount's altitude alignment has deteriorated such that the mounts polar axis is lying some 19 arc minutes too high.

Looking atan  alternate TPoint model using only 8 terms shows MA (azimuth) error changing from +44 secs to -18 secs (ie opposite polarity), whilst the ME (altitude) error changing from -1159 to -1063 (ie same polarity & similar magnitude ).  Drift Checks in December showed Polar Alignment Errors of only 1.4 arc min based on star drift in West Sky (70 deg W of S , Dec 0 deg), but a Polar Alignment Error of 8.7 arc min based on star drfit in East Sky (65 deg E of S, Dec 0 deg)

Polar Alignment Information from New Mapping Run 155 data points.  Best TPoint Model 16 terms		Polar Alignment Information from Earlier Mapping  (2018-05-17) 121 data points. Best TPoint Model 12 terms
Polar Alignment Information from New Mapping Run 155 data points.  Alternate TPoint Model 8 terms		Polar Alignment Information from Earlier Mapping  (2018-05-17) 121 data points.  Alternate TPoint Model 8 terms

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