David's Astronomy Pages Notes - Session 891 (2021-04-25)

Notes (S890)

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Notes (S892)

	Session Aims & Highlights
	- Observing Result  - Night Summary Plot  - Session Event Log
	Operational Issues
	- Critical Issues (0),  Major Issues (0),  Minor Issues (4),  Small Defects (2),  Continuous Improvement (10)
	Images from 2021-04-25 >>      [ Local Files >> ]
	Investigation - Slewing Scope Path Resolution

Session Aims & Highlights (2021-04-25)

Main aims

1. MeadeLX200GPS. Test out new 'bypass date prompts' method for resolving a show-stopping scope connection issue that had prevented use of the MeadeLX200GPS ascom telescope driver since the issue arose during session S887 (2021-04-16).  Ensure that the driver is available as a ready-to-go alternative to using MeadeGeneric driver, which has been used during session S888-S890.
2. Targets. Acquire images of a selection of variable stars, nearby stars, comets & deep sky targets as allowed by conditions

Equipment & Software

• 12" LX200 and ST-10XME
• 80mm APO and ZWO ASI 178MC
• CCDApp2, TheSky6, CCDSoft5, PHD2,  DeviceHub 6.5.1.0,  MeadeLX200GPS, UPB 1.5, ASCOM 6.5 SP1
• Pegasus UPB & Motor Focus, TCF-S
• SharpCap 3.2, PHD2  2.6.9Dev4
   
• AstroMain 3.39.3,  AstroPlan 1.21.6,  AstroShCap 1.3.11, AstroGuard 1.6,   AstroVOE 1.7, AstroSN 1.5,  AstroProtect 1.6
  (AstroWeather 1.12.4, AstroAllSky 3.10.3, AstroObsCam 1.5.5 )

Highlights

•   MeadeLX200GPS driver.  The new 'bypass date prompts' method for remediating a show-stopping scope connection issue when using MeadeLX200GPS telescope driver with AutoSetTime option worked successfully, and allowed session to be commenced in automated mode using 'AutoStart'
•   Sky Quality.  Sky Transparency gradually deteriorated until  it became so bad session had to be suspended. Resulting in fewer targets than hoped.

Notes:

Summary Plots & Logs

Observing Plan

Observing Result

Dome & Scope Slewing Performance

Slew/Centering Performance

Guiding Performance Dec Notes : Run 8 (black) failed due wrong Dec Guide Mode (South Guide Mode not suited to southerly star drift) Run 6 (red) impacted by periods of ineffective Dec guiding Run 3 and Run 5 (orange) impacted by periods of ineffective Dec guiding

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)

Actual Weather vs Pre-Session Weather Forecast

Session Event Log

Time     Event Detail 22:06:10 Session Monitoring AutoStart monitoring for Live Session opportunity starting between 22:06 & 03:13 22:06:13   AutoStart Delayed Session delayed due to cloud 22:15:44 Session AutoStarting Session autostarting (22:15) 22:16:14 Session Created Live Session Created (2021-04-25 S00891, ImageSaveNum: 891001) 22:16:17   Scope Switched On Telescope Power has been switched on via UPB Powerbox. 22:17:46   Services Started Observatory Services started 22:17:57 Observatory (Auto) Observatory placed in Fully-Automated Mode 22:17:59 Session Pending Session pending (2021-04-25) 22:18:01 Session Initiating Session initiating (2021-04-25) 22:18:03   Plan Requested Observing Plan requested from AstroPlan (1.21.6) 22:19:45   Plan Loaded Observing Plan loaded to queue (, Plan ID: 630) 22:20:02   Camera1 Connected SBIG Camera Connected (set point -15°C) 22:20:08   Telescope Connected Telescope Connected (TheSky6) 22:20:18 Session Equilibration Session ready for dome & camera equilibration 22:21:05   Dome Opened Dome opened (opening time 46s) 22:21:08   Equilibration Started Dome Equilibration started 22:26:00   Equilibration Ended Dome Equilibration ended (4.9 mins total) 22:26:02 Session Running Session running 22:26:04   Queue Started Observing Queue started (21 targets selected) 22:27:14       Focusing Started-Foc1 Foc1 Focusing Started (TCF-S) 22:30:46       Focusing Completed Foc1 AutoFocus Completed (Profile No 1, wide) 22:32:38       Focusing Completed Foc1 AutoFocus Completed (Profile No 1) 22:33:05       Focusing Started-Foc2 Foc2 Focusing Started (Secondary Scope, using ShCap) 22:35:32       Focusing Completed Foc2 AutoFocus Completed (Profile No 2, wide) 22:37:24       Focusing Completed Foc2 AutoFocus Completed (Profile No 2) 22:37:41       Focusing Checked Foc2 Focusing Check Succeeded 22:42:48     Target Started (1/21) Target started (1/21, NGC 4227 w/SN2021biz) 22:47:46       Focusing Started-Foc1 Foc1 Focusing Started (TCF-S) 22:49:54       Focusing Completed Foc1 AutoFocus Completed (Profile No 3) 23:02:49     Target Completed Target partially completed (1/21, NGC 4227 w/SN2021biz) 23:02:51     Target Started (2/21) Target started (2/21, C/2020 T2 (Palomar)) 23:06:48       Focusing Started-Foc1 Foc1 Focusing Started (TCF-S) 23:08:52       Focusing Completed Foc1 AutoFocus Completed (Profile No 4) 23:21:58     Target Completed Target completed (2/21, C/2020 T2 (Palomar)) 23:22:00     Target Started (3/21) Target started (3/21, Nova Per 2020 (CV)) 23:26:27       Focusing Started-Foc1 Foc1 Focusing Started (TCF-S) 23:28:28       Focusing Completed Foc1 AutoFocus Completed (Profile No 5) 23:37:04     Target Completed Target completed (3/21, Nova Per 2020 (CV)) 23:37:06     Target Started (4/21) Target started (4/21, AT2021hkn) 23:40:43       Focusing Started-Foc1 Foc1 Focusing Started (TCF-S) 23:42:34       Focusing Completed Foc1 AutoFocus Completed (Profile No 6) 23:48:12     Target Completed Target completed (4/21, AT2021hkn) 23:48:14     Target Started (5/21) Target started (5/21, NGC 3310 w/SN2021gmj) 23:52:21       Focusing Skipped Foc1 focusing skipped - star is too dim (TCF-S) 00:09:25     Target Completed Target completed (5/21, NGC 3310 w/SN2021gmj) 00:09:27     Target Started (6/21) Target started (6/21, UGC 6930 w/SN2020rcq) 00:13:00       Focusing Started-Foc1 Foc1 Focusing Started (TCF-S) 00:15:12       Focusing Completed Foc1 AutoFocus Completed (Profile No 7) 00:25:52     Target Completed Target completed (6/21, UGC 6930 w/SN2020rcq) 00:25:54     Target Started (7/21) Target started (7/21, NGC 4774 w/AT2021cjd) 00:28:16   SoftSuspend Called Soft Suspend is called due to Deteriorating Conditions (too few stars) 00:28:51   SoftSuspend Cancelled Soft Suspend is cancelled due to Improved Conditions 00:29:15       Focusing Skipped Foc1 focusing skipped - unable to find a star (TCF-S) 00:33:57   SoftSuspend Called Soft Suspend is called due to Deteriorating Conditions (too few stars) 00:41:47   SoftSuspend Cancelled Soft Suspend is cancelled due to Improved Conditions 00:46:47     Target Completed Target completed (7/21, NGC 4774 w/AT2021cjd) 00:47:08     Target Started (8/21) Target started (8/21, MCG +6-30-84 w/SN2021K) 00:49:28   SoftSuspend Called Soft Suspend is called due to Deteriorating Conditions (too few stars) 00:49:53   SoftSuspend Cancelled Soft Suspend is cancelled due to Improved Conditions 00:50:28       Focusing Started-Foc1 Foc1 Focusing Started (TCF-S) 00:52:21       Focusing Completed Foc1 AutoFocus Completed (Profile No 8) 00:53:58   SoftSuspend Called Soft Suspend is called due to Deteriorating Conditions (too few stars) 00:54:08   SoftSuspend Cancelled Soft Suspend is cancelled due to Improved Conditions 01:00:49   SoftSuspend Called Soft Suspend is called due to Deteriorating Conditions (too few stars) 01:02:24   SoftSuspend Cancelled Soft Suspend is cancelled due to Improved Conditions 01:04:54   SoftSuspend Called Soft Suspend is called due to Deteriorating Conditions (too few stars) 01:08:01     Target Completed Target completed (8/21, MCG +6-30-84 w/SN2021K) 01:08:03   Queue Paused Queue paused For Session Suspension 01:08:05 Session Suspended Session suspended 01:08:55   Dome Closed Dome closed (closing time 50s) 01:28:22     Target Cancelled Target cancelled (9/21, UGC 9083 w/AT2021buk) due to cloud 01:50:14     Target Cancelled Target cancelled (10/21, NGC 6223 w/SN2021bls) due to cloud 02:04:06     Target Cancelled Target cancelled (11/21, AT2021gux (CV)) due to cloud 02:13:32     Target Cancelled Target cancelled (12/21, GCVS R CrB) due to cloud 02:21:37     Target Cancelled Target cancelled (13/21, HIP 87937) due to cloud 02:31:35     Target Cancelled Target cancelled (14/21, GCVS AM Her) due to cloud 02:51:12     Target Cancelled Target cancelled (15/21, NGC 4165 w/SN2021gno) due to cloud 03:03:30     Target Cancelled Target cancelled (16/21, GCVS BL Lac) due to cloud 03:12:40     Target Cancelled Target cancelled (17/21, GCVS HH And) due to cloud 03:20:55     Target Cancelled Target cancelled (18/21, WDS GRB 34) due to cloud 03:31:52     Target Cancelled Target cancelled (19/21, AT2021hqd (CV)) due to cloud 03:39:54     Target Cancelled Target cancelled (20/21, 61 Cyg) due to cloud 04:00:36     Target Cancelled Target cancelled (21/21, GCVS U Her) due to cloud 04:00:41   Queue Completed Job Queue completed 04:00:45 Session Closing Session closing 04:00:50   Dome Closed Dome already closed (closed at 01:08, closing time 50s) 04:01:49   Dome Parked Dome parked (parking time 50s), Az: 90.0 deg 04:02:30   Telescope Parked Telescope parked (parking time 37s) 04:03:00   Telescope Switched Off Telescope Power has been switched off via UPB Switch. 04:03:47   Services Stopped Night Services stopped 04:03:49 Session Housekeeping Housekeeping Started (Cleanup FITS, Create Fits Summary, Transfer Files) 04:04:01 Session Finished Session Finished

Session Alerts

Time     Alert Detail 00:00:03 Dome Alert DomeRecords have stopped updating 00:00:23 Dome Alert DomeRecords have resumed updating

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Operational Issues (2021-04-25, S891)

• Critical Issues (0)
• Major Issues (0)
• Minor Issues (4)
• Small Defects (2)
• Continuous Improvement (10)

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Critical Issues

• None

Major Issues

• None

Minor Issues

• Slew to first target (NGC 4227) has unexpectedly large pointing error of 22.9' .  Slew to Target 1/21 (NGC 4227) had a realtime pointing error of 22.89'  (W: -15.42', N: -16.92'). Whilst the following corrective jog had an estimated scope change of : 22.82 arc mins (W= 15.34', N= 16.90'), second locate frame indicated that scope had seemingly hardly move and still showed a pointing error of 22.71'  (W: 16.18', N: 15.94') . This was corrected by the next corrective jog and the final locate frame showed pointing of 0.36'  (W: -0.35', N: 0.09').  Slews to later targets had normal pointing errors ranging from 1.2' to 3.3'.    NGC 4227 was at a uncomplicated sky position (Az 166.4 / Alt 65.7) and its slew result is unexplained.  Reviewing slew & centering data from indicates that the Locate frame following the slew actually had a pointing error of only 1.1' and the reason that a realtime error of 22.9' was determined in realtime was due to a mis-linking of the image.  This is evident both from visual inspection of the image (the target is clearly close to the center of the frame) and the reported rotation angle of 356.7 degs is some 180 degs different from the actual rotation angle of 179.3 deg.  Believing the 22.9' error in realtime the job queue moved the telescope scope some 22.9' which explains why the estimated scope change and explains why the second locate frame had a pointing error of 22.7'.   Plate Linking code should really not have accepted a image rotation angle of 356.7 for CCD image from main scope when it is evidently well outside any reason working tolerance surrounding the notional setup angle of 180 deg.
  Issue is understood. (Session)
   
• First Locate Frame for Target 1/21 (NGC 4227) slipped through Plate Solution with invalid rotation angle. Realtime plate solution for #891001 was solved with rotation angle of 356.7 degs which is some 180 degs different from the actual rotation angle of 179.3 deg.  At the moment DoImageLink uses PositionAndSync () routine which tests the results from DoImageLink(SyncMode, x, y) and updates BestMatch data if the following condition statement is true
   " If (varActiveStars >= 8) Or ((varActiveStars >= 4) And (GetMisRotation(varScreenRotation) > -RotateTolerance) And (GetMisRotation(varScreenRotation) < RotateTolerance)) "    It would seem that the plate solution slipped through the condition statement because the image had Active Stars=9.  
  (Camera and its notional rotation angle is already accounted for by reference to gUseCam2Linking variable (True/False) from within the GetMisRotation() routine.
  RotateTolerance is set to RotateTolerance_Fine before calling PositionAndSync()  where RotateTolerance_Fine = 3  (which is set in SetInitialParams routine '
  (The alternative variable RotateTolerance_Course = 10 is not currently used anywhere)
  Condition statement changed in AstroMain 3.39.8 to
  " If (varActiveStars >= 20 Or Math.Abs(GetMisRotation(varScreenRotation)) > RotateTolerance) "
  Fixed 2021-05-04 (AstroMain 3.39.8)
   
• The Get UTC Times from Telescope show varying time offsets from Computer's UTC time ranging from 2 to 18s (2021-04-28).  Investigation carried out following daytime testing.  Values returned to client program (AstroMain) indicate an apparent difference of between 2 and 6s between Telescope UTCDate and Computer UTCDate. Looking at MeadeGeneric Log it seem that was a real (or apparent) computer to telescope time difference of around 2s  (probably a time delay getting date/time into telescope during connection + delay in LX200 whilst it set the clock + a time delay getting date/time back out from the telescope) . It seems that in addition to the basic 2s difference a further 0 to 3s delay is probably attributable to DeviceHub with it returning either a freshly obtained UTC value or a slightly less fresh UTC value depending on whereabouts it is in its slow polling rate cycle.    A bit later  the time difference jump to a larger value (with the time difference typically being up to 12 to 18s).  This was initially harder to explain - but is now explained as being data collected after the telescope was parked but before the ASCOM telescope/driver was disconnected. MeadeGeneric log does not shown any completed Get UTCDates messages after the scope is parked. It seems that scope simply can’t/didn’t return a UTCDate/Time when it was parked, or the driver chooses not to fetch it when the scope is parked. Then after some sort of timeout period a time (but not the current UT time) is somehow returned.
  TIssue understood  (MeadeGeneric / DeviceHub / LX200GPS )
   
• Log file contain multiple messages "Network Monitor |  Info |  Check.Network | Network Monitor loop has taken ..." (2021-04-28) This was due to network being down for several hours on 2021-04-28  (10:27 to 15:56).   Error messages should be curtailed or decimated.   Log message S2 and S3 elements need to be switched around.
  Done 2021-04-29 (AstroMain 3.39.5)

Small Defects

• After parking scope but before scope is disconnected,  the Tracking and Status field on AstroMain's Observatory tab both show the scope as Tracking. At such times the Tracking should be off and Status should show 'Parked' . ObsViewer fields look to be correct and show scope as 'Parked'
  Fixed 2021-04-28 (AstroMain 3.39.5)
   
• After disconnection of both Scope and Dome, the Dome object sends multiple log messages "Get objDome.Slaved | Exception : Object reference not set to an instance of an object" (2021-04-27).   Log message is  "Dome | Get objDome.Slaved |   Error | Exception whilst getting Dome.Slaved property, Object reference not set to an instance of an object.
  Fixed 2021-04-28 (AstroMain 3.39.5)

Continuous Improvement

• Remove blue HFD (zero value) points from Foc1 Wide Focus Profile Plots. Problem due to HFD not being explicity set to vcNull when using Wide Focus Mode.
  Done 2021-04-26 (AstroMain 3.39.4 )
   
• Add a scope power traffic light to the 'Scope Power' area of AstroMain's More/Obs tab. This avoids the user needing to refer back to the ObsViewer window to see the Scopes' current power state.
  Done 2021-04-28 (AstroMain 3.39.5)
   
• The reporting of Pulsar trace log filename should be be delayed until all service are started.  Currently the report / log message interrupts the flow of report messages.
  Done 2021-04-28 (AstroMain 3.39.5)
   
• Angular change tabulated in ScopePath table in log file to be changed from arc mins to arc degs (3 d.p.). Static points should be removed from table.
  Done 2021-04-28 (AstroMain 3.39.5)
   
• Reduce the number of calls to Scope.Azimuth and Scope.Altitude during slewing.  It is thought that calls to Get Azimuth and Get Altitude might be slowing down the processing of requests to the MeadeGeneric telescope driver (due to calculating Az/Alt from RA/Dec coordinates).  In many cases calls to get Az/Alt are unnecessary as there is no new RA/DEC position data to provide a new segment one the slew path.  Although this modifcation was implemented in AstroMain 3.39.4 (2021-04-27) testing showed that the change failed to give the improvement hoped. 
  Done 2021-04-27 (AstroMain 3.39.4 )
   
• Save LX200 Scope Driver (MeadeGeneric or MeadeLX200GPS) to program settings (to be available upon next program restart)
  Done 2021-04-28 (AstroMain 3.39.5)
   
• Query. Is it necessary/appropriate to write 'SlewDomeToAzimuth | Resetting DomeSlewStopped as dome appears to be slewing again' message to log file, what activity is it logging and why (2021-04-27).  Message hidden from appearing SlewTheSkyScope  (the reset is still performed however)
  Done 2021-04-28 (AstroMain 3.39.5)
   
• Scope COM Port to be shown on ObsViewer picture.   To be written 'Scope on COM7' in similar fashion to 'Dome on COM9'
  Done 2021-04-28 (AstroMain 3.39.5)
   
• Disable logging of 'Check PulsarDomeLog Fail | Pulsar Dome Log has stopped updating' messages when scope is disconnected. Fixed by only allowing message to be shown once (unless subsequently reset by the Dome log begin to update again.
  Done 2021-04-28 (AstroMain 3.39.5)
   
• Removing trailing # symbol (if present) from Handbox display message returned from scope. The applies to message returned by either Scope.CommandString(":ED#", true)  or Scope.Action("handbox","readdisplay").
  Done 2021-04-29 (AstroMain 3.39.5)
   
• Rationalise/update Logfile S1 & S3 columns.  Aim is to provide greater clairty to information in log file.
  Get,  Set,  Start,  Stop,  Check,  Calc, :  Slew,  Take,  Park, Open, Close,  WaitOn, Read,  Update,
  A new WriteLogFileRecord2() routine has been added with S3 element divided in S3a and S3b parts, written  LAlign(S3a, 7) + " " + LAlign(S3a, 20)
  and process of converting existing WriteLogFileRecords has begun.  For consistency the S3 element in existing WriteLogFileRecord () is widened to 28 char, written LAlign(S3, 28)
  Done 2021-04-29 (AstroMain 3.39.5)

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