David's Astronomy Pages Notes - Session 792 (2020-07-03)

Notes (S791)

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Notes (S793)

	Session Aims & Highlights
	- Observing Result  - Night Summary Plot  - Session Event Log
	Operational Issues
	- Critical Issues (0),  Major Issues (2),  Minor Issues (5),  Continuous Improvement (0)
	Images from 2020-07-03 >>

Session Aims & Highlights (2020-07-03)

Main aims

1. Targets. Aquire variety of targets if conditions allowed

Equipment & Software

• 12" LX200 and ST-10XME
• 80mm APO and ZWO ASI 178MC
• CCDApp2, TheSky6, CCDSoft5, PHD2,  DeviceHub 4.6.1.10, UPB 1.5 
• Pegasus UPB & Motor Focus, TCF-S
• SharpCap 3.2, PHD2  2.6.8
   
• AstroMain 3.25.6,  AstroGuard 1.4.2,   AstroPlan 1.15.3,  AstroShCap 1.2.22, AstroVOE 1.3.6
  (AstroWeather 1.10.8, AstroAllSky 3.6)
  

Highlights

• None

Lowlights

• Cloud. Sky quickly clouded over and caused poor imaging/poor autoguiding and eventually prevented acquiring the planned southern targets

Summary Plots & Logs

Observing Plan

Observing Result (Southern targets added as ToO targets)

Dome & Scope Slewing Performance

Slew/Centering Performance

Guiding 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) Pre-Session Weather forecast showed variable skies range from 5 to 50% cloud cover,  light winds (wind 7mph) and a minimum temperature of 6°C. In the event conditions were clear and calm through the whole night, with a minimum temperature of around 4°C

Session Event Log

Time     Event Detail 23:34:52   Camera1 Connected SBIG Camera Connected (set point -15°C) 23:34:54 Session Created Live Session Created (2020-07-03 S00792, ImageSaveNum: 792001) 23:35:14   Scope Switched On Telescope Power has been switched on via UPB Powerbox. 23:37:54   Services Started Observatory Services started 23:38:05   Telescope Connected Telescope Connected (TheSky6) 23:39:20   Dome Opened Dome opened (opening time 46s) 23:39:27   Camera1 Connected SBIG Camera Connected (set point -15°C) 23:41:05       Focusing Started-Foc1 Foc1 Focusing Started (TCF-S) 23:43:57       Focusing Completed Foc1 AutoFocus Completed (Profile No 1) 23:43:59       Focusing Started Foc2 Focusing Started (Secondary Scope, using ShCap) 23:46:26       Focusing Completed Foc2 AutoFocus Completed (Profile No 2) 23:46:38       Focusing Started Foc2 Focusing Started (Secondary Scope, using ShCap) 23:49:12       Focusing Completed Foc2 AutoFocus Completed (Profile No 3) 23:49:25       Focusing Started Foc2 Focusing Started (Secondary Scope, using ShCap) 23:52:04       Focusing Completed Foc2 AutoFocus Completed (Profile No 4) 23:54:34 Observatory (Auto) Observatory placed in Fully-Automated Mode 23:54:36 Session Pending Session pending (2020-07-03) 23:54:38 Session Initiating Session initiating (2020-07-03) 23:54:40   Plan Requested Observing Plan requested from AstroPlan (1.15.3) 23:55:31   Plan Loaded Observing Plan loaded to queue (2020-07-03 V1 BEST PLAN, Plan ID: 521) 23:55:35   Camera1 Connected SBIG Camera Connected (set point -15°C) 23:55:39   Telescope Connected Telescope Connected (TheSky6) 23:55:52 Session Equilibration Session ready for dome & camera equilibration 23:55:55   Equilibration Started Dome Equilibration started 23:57:43   Equilibration Skipped Dome Equilibration skipped by user 23:57:45 Session Running Session running 23:57:47   Queue Started Observing Queue started (11 targets selected) 00:12:43     Target Started (1/11) Target started (1/11, HIP 87937) 00:19:32       Focusing Started-Foc1 Foc1 Focusing Started (TCF-S) 00:22:42       Focusing Completed Foc1 AutoFocus Completed (Profile No 5) 00:25:26     Target Completed Target partially completed (1/11, HIP 87937) 00:25:29     Target Started (2/11) Target started (2/11, GCVS CY Lyr) 00:35:55     Target Completed Target partially completed (2/11, GCVS CY Lyr) 00:35:57     Target Started (3/11) Target started (3/11, GCVS CI Cyg) 00:36:56     Target Failed Target failed due to aborted (3/11, GCVS CI Cyg) 00:36:58   Queue Aborted Job Queue aborted 00:37:52   Telescope Parked Telescope parked (parking time 41s) 00:38:09   Telescope Switched Off Telescope Power has been switched off via UPB Powerbox. 00:39:03   Services Stopped Observatory Services stopped 00:41:53   Obs.Manager Started Obs.Manager started 00:41:55   Obs.Overseer Started Obs.Overseer started 00:41:59   Services Started Observatory Services started 00:43:30   Scope Switched On Telescope Power has been switched on via UPB Powerbox. 00:45:07   Services Started Observatory Services started 00:48:42   Services Started Observatory Services started 00:49:06   Telescope Connected Telescope Connected (TheSky6) 00:49:16   Camera1 Connected SBIG Camera Connected (set point -15°C) 00:49:22 Observatory (Auto) Observatory placed in Fully-Automated Mode 00:49:26 Session Pending Session pending (2020-07-03) 00:49:28 Session Initiating Session initiating (2020-07-03) 00:49:30   Plan Loaded Observing Plan loaded to queue (2020-07-03 V1 ACTIVE PLAN S792, Plan ID: 521) 00:49:32   Camera1 Connected SBIG Camera Connected (set point -15°C) 00:49:33   Telescope Connected Telescope Connected (TheSky6)

Session Alerts

Time     Alert Detail -- No Alerts                --

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Operational Issues (2020-07-03, S792)

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

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Critical Issues

• None

Major Issues

• Dome not moving when scope slewed even though Dome is set to slaved in DeviceHub. Dome didn't appear to move to targets when scope was ordered to slew to Target 1 (HIP 87937), Target 2 (CY Lyr) or Target 3. (CI Cyg) even though Dome was slaved to Telescope in DeviceHub.   Previously the dome slewed ok to Near Zenith Focus Field, and arguably was already at a suitable azimuth (179 deg) for Target 1 (Az 179.9deg) and didn't require slewing.  For Target 2 and Target the dome remained at an apparent azimuth of 180 deg.   Dome azimuth appear to remain at 180 deg in AstroMain, even though DeviceHub was used to move the dome to Az 161.  ObsViewer is showing 'Dome Is Parked(Home)  (RED)  and 'Dome is Slewing' (YELLOW) at same time. This issue was a factor in the operational decision to finish the session early.  Examining the Pulsar Trace Log shows that there were no Get requests or Set Azimuth requests made between 00:17:26  and 00:28:23 suggesting that DeviceHub wasn't collecting data from the Dome and wasn't keeping the Dome Slaved to the Scope position.    Although a slew to Az 161 was successfully sent to dome via DeviceHub at 00:28:23, the new dome position wasn't recognised.  Issue was eventually fixed on 2020-10-15 by the installation of Device Hub 6.5.0.1 which has better exception trapping.   Issue deemed closed on 2020-11-06 after there were no similar incidents during the first 8 sessions using the new DH version. 
  Closed 2020-11-06 (Device Hub 6.5.0.1).
   
• SlewToTargetRaDec taking an unexpectedly long time (240s).   SlewToTargetRaDec for Target 1 (HIP 87937, Barnards Star) took an unexpectedly long time. Slew Table shows that telescope was required to make a very short (2 deg) slew from AzAlt 179.3 / 35.7 to AzAlt 179.9 / 37.2  but seemingly took 240s.  Log file shows that Scope Slew from Az/Alt  179.3 / 35.7 to AzAlt 178.8 / 37.2  in 17.1s which is probably about right.    After waiting for 240s or so, Az would have increased from 178.8 to 179.7 . Dome shows a pre-slew azimuth position of 179.0 deg and may not need to have moved to keep in within Slave Tolerance.  Post Slew aziumth was 179.0 with a vcNull slew time (-99).  It is postulated that the SlewTheSkyScopeToRaDec()  routine may have timed out waiting for Dome Slew to finish a slew it never started. Time out is set to 4 minutes in the code (=240s).  Code shows a section of code ' Handling Very Short Dome Slews' has been commented out.   Examining Pulsar Trace Log shows command to Slew Dome (from 179.0) to Azimuth 180.0079. This was completed in 2s and was probably too quick for SlewTheSkyScopeToRaDec()  to recognise that that dome slewing had started before the slew had finished.
  Slew to Target 2 (CY Lyr) also took an unexpectedly long time.  Slew Table shows that scope took 171s to complete 35.7 deg slew but the logfile shows that telescope slew was essentially completed in 22s. The entire slew timed out after 240s as the routine was evidently waiting on the Dome to move, but it was either slipping whilst at 180 deg or the DeviceHub command to slew dome to c. 161 deg at 00:25:28 didn't get through. Examining the Pulsar Trace Log shows that there were no Get requests or Set Azimuth requests made between 00:17:26  and 00:28:23.   As the dome was observed to have not moved to the Target the dome was ordered to move to Az 161 using DeviceHub direct which it did in around 9-10s.   The movement happened physically but wasn't recognised  At 00:29:28 an Abort Slew was sent to the Dome.  Issue was eventually fixed on 2020-10-15 by the installation of Device Hub 6.5.0.1 which has better exception trapping.   Issue deemed closed on 2020-11-06 after there were no similar incidents during the first 8 sessions using the new DH version. 
  Closed 2020-11-06 (Device Hub 6.5.0.1).

Minor Issues

• Telescope unexpectedly appearing to have been just powered up . After waiting some 15 minutes for 1st target to commence the 1st target was commenced.  Unexpectedly the Obs Viewer showed the Scope Power has only just been turned on (16s, 18s, 20s etc). This was confusing as there might have been a problem that had caused the scope power to go off/come back on which could have led to the scope restarting/resuming from a non-parked position with consquential risk of cable rap on collisions with fork base.  Examining the set of ObsPics collected from the session shows that Scope Power On started counting up from Power Up events (0s) at 00:12:10 and again at 00:19:10 (whilst waiting to begin focusing) at  00:23:13 ,  at 00:29:12 (just after starting CY Lyr),  at 00:32:11 (during Cy Lyr) and at 00:46:07.  (Note Power Scope on event at 00:43 was intentional and followed a temporary Parking of the scope at 00:38).  There is no indication that the scope was actually powered off/powered on at these times, but instead the behaviour is more typical of either the UPS Powerbox Switch object being restarted or the Power State becomig momentarily set to 0 or vcNull . The Switch Reconnection events seem to be semi-regular,  based a 7m, 4m, 6m & 3m gaps    Logfile doesn't indicate any cases where ASCOM Switch Object has been restarted. Instead the logfile is noted to show 'Setting DewHeaters' messages occuring at 00:12:08.15,  00:19:08.86, 00:23:09.22, 00:29:09.63 &  00:46:04.46 just before the 'scope power restarts' which suggests that use of Switch Driver is resulting in 'failed requests' for the power status of Switch 1 (LX200).  Code shows that problem is an unintentional sideeffect of trying to utilise a 'user lock' on the Ascom Switch Object.  Code modified to fix the bug.
  Fixed 2020-07-06  (AstroMain 3.25.7)
   
• Obs Viewer showed 'Dome is Parked (At Home)' with Red Circular Flag when dome was at 180 deg.  Problem fixed in code.  The issue only affects the display  and cannot have been the cause of the Dome Slewing problem noted above.
  Fixed  2020-07-06 (AstroMain 3.25.7)
   
• Dome rotation drive is occassionally slipping (drive running but dome not moving). This is a know occasional problem and can occur when rotation drive wheels are tightly positioned against the roof flange.  Unclear if problem is caused by dampness/grease on the roof flange. This issue was a factor in the operational decision to finish the session early. 
  Tested Ok  2020-07-06  (Observatory)
   
• AstroMain froze at 00:49:45 shortly after restarting session / restarting Equilibration State
  Resolved Q4 2020 (AstroMain)
   
• Logfile captured exception getting XY coordinates in CalculatePointingError (Image.RaDectoXY).  Exception caught for 00792001.HIP_87937.FIT. Logfile shows exception affected locate frame  792001 with Error code = 206 (0xce).  but not for locate frames 729002, 792003, 792014 & 792015.  Locate frame 792002 had too few stars and didn't called the CalculatePointingError() routine, but the other frames successfully negioated the routine without exception.   There was no problem calling CalculatePointingError() routine in either of the two previous sessions (S791 & S790) , but did occur once in session (S789,   Frame  00789069.NGC_582.FIT).  Problem didn't stop the Locate frame from being successfully utitlised and the problem is put down to being a glitch.   It seems problem occurs when Linking is achieved with Stars = 5 or 6 but analysig stars shows 'Stars= 0/0' .  Appears to be the same issue that was reported in session S820 (See S820, 2020-10-23 Op. Issues). Issue closed following review 2021-05-13 as Issue resolved or otherwise no longer occurs.
  Closed 2021-05-13 (AstroMain).

Continuous Improvement

• None

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