David's Astronomy Pages Notes - Session 1169 (2023-11-30)

Notes (S1168)

Notes Main

Home Page

Notes (S1170)

	Session Aims & Highlights
	- Observing Result  - Night Summary Plot  - Session Event Log
	Operational Issues
	- Critical Issues (0),  Major Issues (1),  Minor Issues (2),  Small Defects (2),  Continuous Improvement (5)
	Images from 2023-11-30 >>
	Investigation - Pulsar Dome holding up at Az 168°
	AllSky Camera  - Latest Modification to Control Dew

Session Aims & Highlights (2023-11-30)

Main aims

1. Resync Scope.  Resync Scope and conduct short mapping job to improve Slewing accuracy.
2. Targets.  Acquire images of a selection of variable stars, nearby stars, comets & deep sky targets as allowed by sky conditions.
3. 12P/Pons-Brooks. Acquire images of Comet 12P/Pons-Brooks which has been undergoing an outburst.

 Equipment & Software

• 12" LX200 and ST-10XME
• 80mm APO and ZWO ASI 178MC
• CCDApp2, TheSky6, CCDSoft5, DeviceHub 6.6.1.1,  MeadeGeneric 1.3.5.414, UPB 1.5, ASCOM 6.6,  Pulsar Dome Firmware 1.51 & Driver 6.3.10
• Pegasus UPB & Motor Focus, TCF-S
• SharpCap 3.2, PHD2  2.6.11dev4, Siril 1.0.6, deCONZ 1.18.2, ASCOM 6.6 SP1
   
• AstroMain 3.64.9, AstroPlan 1.39.1,  AstroShCap 1.3.15, AstroGuard 1.10.2
  AstroVOE 1.13  AstroSN 1.10.2,  AstroProtect 1.7,  AstroMove 1.12.7
  (AstroWeather 1.23, AstroAllSky 3.19.7,  AstroObsCam 1.11.4, AstroLaunch 1.11.1

Highlights

• ReSync Scope. Scope resynced and short mapping job successfully carried out (11/12 points mapped). Scope Restarted and made 18 target slews with average slew pointing error of just 1.1 arc min.
  Targets.16/40 planned targets observations were completed, with 1 other target partially completed. Other targets failed/cancelled due to cloud. One of these (Jupiter) plus one other additional target (144P ) were also completed as ToO targets.
• 12P/Pons-Brooks. Images of Comet 12P/Pons-Brooks were successfully acquired.
• AstroMain. New version of AstroMain worked successfully and didn't introduce any new issues
•  Dome Slews. 4 Dome slews were affected by significant hold-ups of 172-223s (3 held-up at Az 168°, 1 held up at Az 258°)
    (Hold Up Stats:4/34 slews affected, 12%, 1.4 minutes total hold-up time). 
•  Dome Parking.  Dome left at Az 168° at end of session and didn't parked at correct location and therefore didn't automatically begin re-charging.

Notes:

• .
  

Summary Plots & Logs

Observing Plan

Observing Result

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)

Actual Weather vs Pre-Session Weather Forecast

Session Event Log

Time     Event Detail 17:57:01   CCDSoft Restarting CCDSoft being restarted (to set AutoSave No.) 17:57:26   Camera1 Connected SBIG Camera connected (Set point -25°C) 17:57:28 Session Created Session Created (Live, 2023-11-30 S01169, ImageSaveNum: 1169001) 17:58:48   Automapping Started Automapping started (12 points planned) 18:12:20   Automapping Completed Automapping completed (11 points mapped out of 12 points) 18:21:28   Telescope Parked Telescope parked (parking time 64s) 18:21:43   Telescope State Handbox reads 'Scope parked Turn scope off.' 18:22:24   Telescope Switched Off Telescope Power has been switched off via UPB Switch. 18:23:04   Scope Switched On Telescope Power has been switched on via UPB Powerbox. 18:24:55 Session Monitoring AutoStart monitoring for Live Session opportunity between 18:24 & 06:04 18:24:57 Observatory (AutoStart) Observatory placed in Auto-Start Mode 18:24:59 Session AutoStarting Session autostarting (18:24) 18:25:19   Services Started Observatory Services started 18:25:25 Observatory (Auto) Observatory placed in Fully-Automated Mode 18:25:27 Session Pending Session pending (2023-11-30) 18:25:29 Session Initiating Session initiating (2023-11-30) 18:25:31   Plan Requested Observing Plan requested from AstroPlan (1.39) 18:26:43   Plan Loaded Observing Plan loaded to queue (Plan ID: 943) 18:26:57   Camera1 Connected SBIG Camera connected (Set point -25°C) 18:27:02   Telescope Connected Telescope connected (TheSky6) 18:27:46 Session Running Session running 18:27:48   Queue Started Observing Queue started (40 targets selected) 18:27:52     Target Started (NrZen) Target started (Focus Field 23, HIP 113729) 18:29:18       Focusing Started-Foc1 Foc1 Focusing Started (TCF-S) 18:31:48       Focusing Completed Foc1 AutoFocus Completed (Profile No 1, wide) 18:33:37       Focusing Completed Foc1 AutoFocus Completed (Profile No 1) 18:33:40       Focusing Started-Foc2 Foc2 Focusing Started (Secondary Scope, using ShCap) 18:35:46       Focusing Completed Foc2 AutoFocus Completed (Profile No 2, wide) 18:37:29       Focusing Completed Foc2 AutoFocus Completed (Profile No 2) 18:37:49     Target Completed (NrZen) Target completed (Focus Field 23, HIP 113729) 18:40:57     Target Started (1/40) Target started (1/40, GCVS BL Lac) 18:42:34   PHD2 Communication Restarting PHD2 service (12 incomplete data stream reads) 18:43:24   PHD2 Restarted PHD2 service restarted 18:46:00   PHD2 Communication PHD2 is potentially stalled ('LoopingExposures' Events not detected) 18:46:26   PHD2 Restarted PHD2 service restarted 18:47:37       Focusing Started-Foc1 Foc1 Focusing Started (TCF-S) 18:49:35       Focusing Completed Foc1 AutoFocus Completed (Profile No 3) 18:53:34     Target Completed Target completed (1/40, GCVS BL Lac) 18:53:38     Target Started (2/40) Target started (2/40, AT2023txn) 18:56:44       Focusing Started-Foc1 Foc1 Focusing Started (TCF-S) 18:58:55       Focusing Completed Foc1 AutoFocus Completed (Profile No 4) 19:04:53     Target Completed Target completed (2/40, AT2023txn) 19:04:57     Target Started (3/40) Target started (3/40, UGC 831 w/AT2023wdd) 19:09:03     Dome Slew Dome slew held up at Az. 167.8° (Delay 198s) 19:27:13     Target Completed Target completed (3/40, UGC 831 w/AT2023wdd) 19:27:17     Target Started (4/40) Target started (4/40, NGC 7625 w/SN2023vyl) 19:30:13       Focusing Started-Foc1 Foc1 Focusing Started (TCF-S) 19:32:08       Focusing Completed Foc1 AutoFocus Completed (Profile No 5) 19:48:23     Target Completed Target completed (4/40, NGC 7625 w/SN2023vyl) 19:48:27     Target Started (5/40) Target started (5/40, M31 w/Nova M31 AT2023yoa) 19:52:33     Dome Slew Dome slew held up at Az. 167.9° (Delay 223s) 19:54:22       Focusing Started-Foc1 Foc1 Focusing Started (TCF-S) 19:56:47       Focusing Completed Foc1 AutoFocus Completed (Profile No 6) 20:12:35     Target Completed Target completed (5/40, M31 w/Nova M31 AT2023yoa) 20:12:39     Target Started (6/40) Target started (6/40, UGC 530 w/SN2023yma) 20:15:01       Focusing Started-Foc1 Foc1 Focusing Started (TCF-S) 20:17:00       Focusing Completed Foc1 AutoFocus Completed (Profile No 7) 20:32:59     Target Completed Target completed (6/40, UGC 530 w/SN2023yma) 20:33:03     Target Started (7/40) Target started (7/40, AT2023wvl (CV)) 20:36:35       Focusing Started-Foc1 Foc1 Focusing Started (TCF-S) 20:38:44       Focusing Completed Foc1 AutoFocus Completed (Profile No 8) 20:44:31     Target Completed Target completed (7/40, AT2023wvl (CV)) 20:44:35     Target Started (8/40) Target started (8/40, 12P/Pons-Brooks) 20:48:33       Focusing Started-Foc1 Foc1 Focusing Started (TCF-S) 20:50:57       Focusing Completed Foc1 AutoFocus Completed (Profile No 9) 21:02:38     Target Completed Target completed (8/40, 12P/Pons-Brooks) 21:02:42     Target Started (9/40) Target started (9/40, AT2023tvi (CV)) 21:05:21       Focusing Skipped Foc1 focusing skipped - star is too dim (TCF-S) 21:11:20     Target Completed Target completed (9/40, AT2023tvi (CV)) 21:13:37     Target Started (10/40) Target started (10/40, AT2023uzx (CV)) 21:16:27       Focusing Started-Foc1 Foc1 Focusing Started (TCF-S) 21:18:37       Focusing Completed Foc1 AutoFocus Completed (Profile No 10) 21:25:10     Target Completed Target completed (10/40, AT2023uzx (CV)) 21:25:57     Target Started (11/40) Target started (11/40, GCVS HH And) 21:30:04     Dome Slew Dome slew held up at Az. 258.0° (Delay 195s) 21:32:16       Focusing Started-Foc1 Foc1 Focusing Started (TCF-S) 21:33:18       SoftSuspend Called Soft Suspend is called due to Deteriorating Conditions (too few stars) 21:34:26       Focusing Completed Foc1 AutoFocus Completed (Profile No 11) 21:36:26     Target Completed Target completed (11/40, GCVS HH And) 21:36:28   Queue Paused Queue paused for Session Suspension 21:36:31 Session Suspending Session suspending 21:37:18   Dome Closed Dome closed (closing time 50s) 21:37:21 Session Suspended Session suspended 21:47:22     Target Cancelled Target cancelled (12/40, Jupiter) due to cloud 22:06:23     Target Cancelled Target cancelled (13/40, UGC 68 w/SN2023xqn) due to cloud 22:28:42     Target Cancelled Target cancelled (14/40, AT2022yeu (CV)) due to cloud 22:37:19 Session Resuming Session resuming 22:38:04   Dome Opened Dome opened (opening time 45s) 22:38:07 Session Running Session running 22:38:09   Queue Resumed Observing Queue resumed 22:38:11     Target Started (15/40) Target started (15/40, SN 2023bid) 22:56:27     Target Completed Target completed (15/40, SN 2023bid) 22:56:31     Target Started (16/41) Target started (16/41, Jupiter, ToO) 23:03:09     Target Completed Target completed (16/41, Jupiter, ToO) 23:03:13     Target Started (17/41) Target started (17/41, M33 w/AT2023ypg) 23:18:33     Target Completed Target partially completed (17/41, M33 w/AT2023ypg) 23:18:38     Target Started (18/41) Target started (18/41, SN 2022mww) 23:21:15       Focusing Started-Foc1 Foc1 Focusing Started (TCF-S) 23:23:43       Focusing Completed Foc1 AutoFocus Completed (Profile No 12) 23:40:02     Target Completed Target completed (18/41, SN 2022mww) 23:40:06     Target Started (19/41) Target started (19/41, AT2023xum) 23:43:12       Focusing Started-Foc1 Foc1 Focusing Started (TCF-S) 23:45:14       Focusing Completed Foc1 AutoFocus Completed (Profile No 13) 00:01:41     Target Completed Target completed (19/41, AT2023xum) 00:01:45     Target Started (20/41) Target started (20/41, AT2023wbv (CV)) 00:04:24       Focusing Started-Foc1 Foc1 Focusing Started (TCF-S) 00:06:21       Focusing Completed Foc1 AutoFocus Completed (Profile No 14) 00:12:24     Target Completed Target completed (20/41, AT2023wbv (CV)) 00:12:29     Target Started (21/41) Target started (21/41, UGC 3174 w/SN2023mut) 00:15:55       Focusing Started-Foc1 Foc1 Focusing Started (TCF-S) 00:18:08       Focusing Completed Foc1 AutoFocus Completed (Profile No 15) 00:33:55     Target Completed Target completed (21/41, UGC 3174 w/SN2023mut) 00:34:00     Target Started (22/42) Target started (22/42, 144P/Kushida, ToO) 00:37:29       Focusing Started-Foc1 Foc1 Focusing Started (TCF-S) 00:39:53       Focusing Completed Foc1 AutoFocus Completed (Profile No 16) 00:50:49     Target Completed Target completed (22/42, 144P/Kushida, ToO) 00:50:53     Target Started (23/42) Target started (23/42, AT2023xzr) 00:59:53       SoftSuspend Called Soft Suspend is called due to Deteriorating Conditions (too few stars) 01:02:05     Target Failed (23/42) Target failed due to (23/42, AT2023xzr) 01:02:07   Queue Paused Queue paused for Session Suspension 01:02:09 Session Suspending Session suspending 01:04:14 Session Suspended Session suspended 01:04:24   Dome Closed Dome closed (closing time 135s) 01:09:46     Target Cancelled Target cancelled (24/42, C/2017 K2 (PANSTARRS)) due to cloud 01:21:51     Target Cancelled Target cancelled (25/42, AT2022vdr (CV)) due to cloud 01:41:51     Target Cancelled Target cancelled (26/42, AT2023ru (CV)) due to cloud 01:55:17     Target Cancelled Target cancelled (27/42, GCVS SU Tau) due to cloud 02:07:07     Target Cancelled Target cancelled (28/42, AT2021afkt (CV)) due to cloud 02:19:10     Target Cancelled Target cancelled (29/42, GCVS DX Cnc) due to cloud 02:30:53     Target Cancelled Target cancelled (30/42, GCVS U Mon) due to cloud 02:49:34     Target Cancelled Target cancelled (31/42, 29P/Schwassmann-Wachmann) due to cloud 03:06:18     Target Cancelled Target cancelled (32/42, 103P/Hartley) due to cloud 03:20:50     Target Cancelled Target cancelled (33/42, 61P/Shajn-Schaldach) due to cloud 03:41:10     Target Cancelled Target cancelled (34/42, NGC 3705 w/SN2022xxf) due to cloud 04:03:30     Target Cancelled Target cancelled (35/42, UGC 6608 w/SN2022zvr) due to cloud 04:25:50     Target Cancelled Target cancelled (36/42, UGC 6265 w/SN2023wcw) due to cloud 04:48:10     Target Cancelled Target cancelled (37/42, M101 w/SN2023ixf) due to cloud 05:10:30     Target Cancelled Target cancelled (38/42, NGC 3690 w/SN2023wrk) due to cloud 05:32:51     Target Cancelled Target cancelled (39/42, NGC 4611 w/SN2023dtz) due to cloud 05:54:50     Target Cancelled Target cancelled (40/42, UGC 9002 w/SN2023pls) due to cloud 06:16:50     Target Cancelled Target cancelled (41/42, NGC 5532 w/SN2023omo) due to cloud 06:49:10     Target Cancelled Target cancelled (42/42, NGC 4995 w/SN2023gfo) due to too few stars 06:49:15   Queue Completed Job Queue completed 06:49:21 Session Closing Session closing 06:49:26   Dome Closed Dome already closed (closed at 01:04, closing time 135s) 06:52:34     Dome Slew Dome slew held up at Az. 168.1° (Delay 172s) 06:52:36   Dome Park Aborted Dome Park aborted (0s, Az=168.1°) 06:53:46   Telescope Parked Telescope parked (parking time 68s) 06:54:01   Telescope State Handbox reads 'Scope parked Turn scope off.' 06:54:23   Telescope Switched Off Telescope Power has been switched off via UPB Switch. 06:55:49   Services Stopped Night Services stopped 06:55:52 Session Finishing Session Finishing started (Create Fits Summary, Transfer Files) 06:56:12 Session Finished Session Finished

Session Alerts & Alarms

Session: 2023-12-01 (General) Time     Type       Name Detail 17:31:04 Yellow Alert Shutter Battery Shutter battery level has fallen below 88% 17:31:44 Green Clear Shutter Battery Shutter battery level has climbed above 95% 17:32:14 Red Alarm Dome Opening Dome failed to finish opening after 140s (ShutterState=Opening) 17:37:41 Red Alarm Dome Opening Dome failed to finish opening after 140s (ShutterState=Opening) 17:39:46 Yellow Alert Shutter Battery Shutter battery level has fallen below 88% 17:40:46 Green Clear Shutter Battery Shutter battery level has climbed above 95% 17:41:11 Red Alarm Dome Closing Dome closure hasn't finished after 140s (ShutterState=Closing) 17:43:03 Red Alert Shutter Battery Shutter battery level has fallen below 85% 17:43:16 Green Clear Shutter Battery Shutter battery level has climbed above 95% 17:52:47 Red Alert CcdCamera CcdCamera appears to be frozen (last cycle at 17:52:11) in section 'GetCameraProperties' 17:53:07 Green Clear CcdCamera CcdCamera has resumed again (17:53) after 0.1 mins Session: 2023-11-30 (S01169) Time     Type       Name Detail 18:27:50 Yellow Alert PHD2 Alert No. of incomplete PHD2 stream reads has exceeded 5 18:43:52 Yellow Alert PHD2 Alert No. of incomplete PHD2 stream reads has exceeded 5 18:57:48 Green Clear PHD2 Alert PHD2 stream reading has stablised again 19:09:03 Red Alert Dome Slew Dome slew held up at Az. 167.8° (Delay 198s) 19:09:11 Yellow Alert Dome Discrepency Difference between Dome Az and Telescope Az is > 8 deg (UGC 831) 19:09:13 Yellow Alert Dome Discrepency Difference between Dome Az and Slave Az is > 1 deg (UGC 831) 19:20:51 Yellow Alert Dome Dome has been stationary for more than 15 mins 19:25:26 Green Alarm Dome Dome Movements have begun again (outage 19.7 mins) 19:52:33 Red Alert Dome Slew Dome slew held up at Az. 167.9° (Delay 223s) 19:52:42 Yellow Alert Dome Discrepency Difference between Dome Az and Slave Az is > 1 deg (M31) 21:30:04 Red Alert Dome Slew Dome slew held up at Az. 258.0° (Delay 195s) 21:30:12 Yellow Alert Dome Discrepency Difference between Dome Az and Slave Az is > 1 deg (GCVS HH And) 06:52:34 Red Alert Dome Slew Dome slew held up at Az. 168.1° (Delay 172s) 06:52:37 Red Alert Dome Failed To Park Parking aborted after 3 mins, Rotation Drive wheels are likely to be slipping (Dome at Az 168.1°)

Back to Top

Operational Issues (2023-11-30, S1169)

• Critical Issues (0)
• Major Issues (1)
• Minor Issues (2)
• Small Defects (2)
• Continuous Improvement (5)
  

[ Prev | Next ]

Critical Issues

• None

Major Issues

• Dome Holding up for significant time at Az 168°. For slew to two targets (UGC 831 & M31) and later on for slew to Pre-Park the dome held-up at Az 167.8° - 168.1° for 189s, 223s & 172s.   One slew (to GCVS HH And) also held up for 195s at Az 258°.  Dome was left at Az 168° at end of session instead of it's expected Park Position at Az 90°. The hold-up is very specifically at one or two points, rather general slippage problem. It is possible that the Drive Wheel Tension is too great and isn't allowing the roof flange to move through the drive wheel system (two wheels on outside, one wheel on inside).  It appears that the problem was due to the movement of the dome being heldup where roof flange/rubber trim runs against the flanges between 2 or 3 of the 4 wall sections and compounded by the inner drive wheels wearing away the anti-slip tape on the roof flane creating a divot that the drive system couldn't get out of. It was unclear if the drive tension was incorrect or played any part in this.  Anti-Slip tape was removed, wall flanges filed back by some 3mm and the drive wheel tension adjusted (see Investigation - Pulsar Dome holding up at Az 168°).
  Fixed  2023-12-01 (Pulsar Dome)

Minor Issues

• Test Session on Development.Computer can lead to a SessionStarting ObsCam picture being taken in the Observatory (2023-12-01). Whilst running a playback of 12P/Pons-Brooks on development computer, the action of connecting TheSky6 Telescope led a request to take an ObsCam picture with 'lights on' in the Observatory. This could interfere with imaging in an actual live session should one be currently active.   Investigate if this is a failure to put up a confirmation message, or user clicking ok.  Prehaps the facility should simply not be active at all when running from Development Computer. Fix implemented in AstroMain 3.65.2 which doesn't allow TakeSpecialObsCamImage() to proceed if MachineName doesn't correspond with that of the Observatory Computer.
  Fixed  2023-12-06 (AstroMain 3.65.2)
   
• Issue with PHD2 Server Connection during first target. During Target 1/40 (GCVS BL Lac) an alert was reported at 18:42 just before Guiding Setup with the message . "12 IncompleteReads (Restarting PHD2 service as precaution)" and the job executoer automatically stopped/killed PHD2 and then restarted PHD2 Service. During Guiding Setup an exception was raised whilst trying to set PHD2 Profile to 'Cam2' Profile (ID=1) and Camera/Mount details couldn't be read. The ObsManager issued a warning "Incomplete PHD2 Reads > 5" .  The job executor failed to 'Capture Reference Frame'   and an alert was raised "Check PHD2 Program, PHD2 Stalled (Restarting PHD2 as a precaution)", and at 18:46 PHD2 was again stopped/killed and restarted.  [ A small side effect of killing PHD2 was that two alerts were reported "PHD2 ListeningLoop has unexpectedly stopped" & ."Unable to read data from the transport connection: A blocking operation was interrupted by a call to WSACancelBlockingCall" should probably use a bRestartingPHD2 flag to suspend such reporting ?) . This time the restart was successfully made, PHD2 automatically connected profile TS8/178MC, ID=1) and camera/mount details were successfully reported. Thereafter PHD2 Guiding proceeded without any further issues.  The problem may have arise as the Camera/Mount which were connected due initial Start PHD2 Service where manually disconnected ahead of parking the telescope following short mapping job, and this somehow upset the PHD2 Server connection.  A separate continuous improvement ticket is raised to review the process involved when Parking Scope / Restarting Scope during a session wrt to PHD2 to prevent the issue arising.
  To investigate & fix  2023-12-01 (AstroMain 3.65)

Small Defects

• Add Target Circle for 12P/Pons-Brooks wasn't in correct position on Focus & Main Frame JPG pictures (20:48 ). Target circle for Target 8/40 (12P/Pons-Brooks) is correct on Locate Frames but is incorrect on Focus and Main Frame pictures (Fig 1). Target was replayed later using On-The-Fly Observing in Test Mode (Target ID 2904, Images 1169059-68) which confirmed the issue.    Between the Final Locate Frame (3) and 1st Main Frame there is a 90 px (2.1') shift in telescope pointing.  This is surprising since Final Locate Frame had a pointing error of 0.61' and since pointing error was < 1' no jog adjustment was made.  2nd Locate Frame shows unexpectedly large star trailing of 20px (0.47') in 10s exposure, and Cam2 Reference frame also shows significant star trailing of 48 px (0.82') indicating that there is some relaxation of telescope pointing taking place for some reason (cable hold-up ?).   The 'match brightest stars' operation on the 1st Main Frame referenced back to Final Locate Frame should neverthess still be capable of determining the shift and use it for adjusting the Target Circle.  Target Circle & Ellipse for UGC 530 w/SN2023yma is also incorrectly positioned (TargetID  3073, images 1169046-51).  A new Star Matching algorithm added to AstroMain 3.65.4 (CalculateImageShift() ) and successfully tested against the 12P/Pons-Brooks dataset (Fig  2) from this session (S1169). The algorithm has also been successfully tested against UGC 530  w/SN2023yma dataset from this session (S1169)  and BL Lac datasets from the following two sessions (S1170 & S1170).
  Fixed 2023-12-10 (Session, AstroMain 3.65.4)
   
• Session's Finalised Report File contains a double (duplicated) <hr> line between Observatory Zigbee Network and Map Local Points sections (17:58).  Session S1169's  Report File contains a two successive line breaks rather than a single line break above the Map Local Points section.   The ReportZigbeeNetwork() routine finishes with a ReportLine(). The MapLocalPoints() routine uses ReportLineTitle("Map Local Points", "", TitleType.General1, "").  The FinaliseReportFile() routine does not remove double <hr>. Fixed in AstroMain 3.65.4 by removing the ReportLine from end of the ReportZigbeeNetwork() routine.
  Fixed 2023-12-12 (AstroMain 3.65.5)

Continuous Improvement

• Add Zigbee Shutter Opening/Closing Time to Dome Opening/Closing Event and Alert Messages. e.g.
     Dome Closed (closing time 134s, zigbee 43s)
  Done  2023-12-12 (AstroMain 3.65.5)
   
• Jupiter is too bright for using C Filter that is normally used for Locate Frames. Locate Frames use 3x3 binning and C Filter. Even at lowest exposure time (0.11-0.12s), Jupiter appears elongated due to blooming. This looks bad, could slightly hinder the locate brightest object centering, and could introduce or worsen the ghosting of Jupiter on image frames for the following deep sky target. Special handling should be employed to use a filter with lower light transmissibility, such as V filter or Nd Filter.  Jupiter uses T.LocateMethod = cdBrightStarLocate and  LocateMode is consequently set to cdBrightStarLocate in OB.CentreTarget() routine. Locate frame is taken by call to ImageAndLink(cNoSync, LocateMode, TaskError).  ImageAndLink() routine has code line 
    SetFilter(gDefaultFilter)
  Solution implemented in AstroMain 3.65.5, code changed to 
    If szTargetName = "Jupiter" Then
     SetFilter(10)              ' Use Filter 10 in CFW10 Filter Wheel, normally this is a Neutral Density Filter
   Else
     SetFilter(gDefaultFilter)  ' Use Default Filter, normally this is a Clear Filter (1)
   End If
  Done  2023-12-12 (AstroMain 3.65.5)
   
• Hold back Zigbee Shutter Opening/Closing report lines until the ObsManager Dome Opening/Closing report lines are written. Structurally this looks better on Console/Report File. Need to have a timeout wait feature so that zigbee report line is still written if the ObsManager report line isn't written for some reason.
  SavedShutterMessage is a new varaiable structure that records the report message that needs to be help back.   RecordShutterMessage() is a new routine for recording the report message being held back.  WriteSavedShutterMessage()  is a new routine that reports the previously delayed report message. The  'Dome is opening' or 'Dome is closing' reporting code in manager.vb has been modified to call WriteSavedShutterMessage(). As a catch-all in the ObsWorker has been modified to call WriteSavedShutterMessage() is there is a savedShutterMessage that is more than 10s old, with further catch-all added in the ObsMonitor that calls WriteSavedShutterMessage() is there is a savedShutterMessage that is more than 15s old.
  Done  2023-12-21 (AstroMain 3.65)
   
• Complete backlog of image building and web page documentation from Nov 2023.  6 sessions still incomplete as of 2024-01-01 (S1160-61,  S1166-69). Completed backlog on 2024-02-2.
  Done  2024-03-01 (Website)
   
• Review process involved when Parking Scope / Restarting Scope during a session with respect to the  PHD2 Server Connection.  Cam2 Profile (ID)  Camera/Mount was connected to ok during initial Start PHD2 Service but later on the camera/mount devices were manually disconnected from PHD2 ahead of parking the telescope following short mapping job, and this somehow upset the PHD2 Server connection.   After restarting telescope and beginning the observing run issues arose when trying to setup PHD2 for the first target, with alerts about "Incomplete PHD2 Reads" and the PHD2 Service had to be restarted (twice).  This was performed automatically by the job executor and the session continued on okay, but it took up a little extra time and a Cam2 Reference image wasn't captured as per design.   How should the disconnect / reconnect PHD2 been performed so that the server issues didn't arise.  Fixed in AstroMain 3.66 or earlier sub-version. Closed after review 2024-03-20
  Done  2024-03-20 (AstroMain 3.66, PHD2)

[ Prev | Next ]

Back to Top

Investigation - Pulsar Dome holding up at Az 168°

Issue.
Dome Holding up for significant time at Az 168°.  Dome couldn't park at end of session and left at Az 168°

Description
30 out of 34 slews in session S1169 were normal, but slews to two targets (UGC 831 & M31) and later on for slew to Pre-Park position (Az 90) the dome held-up at Az 167.8° - 168.1° for 189s, 223s & 172s respectively.   One slew (to GCVS HH And) also held up for 195s at Az 258°.  Dome was left at Az 168° at the end of the session instead of it's expected Park Position at Az 90°. The hold-up is very specifically at one or two points, rather general slippage problem.   The dome slewing performance chart from the session is shown below in which the hold-up points are indicated by the red lines radiating away from the outer circle.

Analysis

Previous problems with dome delays and hold-ups was eventually determined in late October 2013 to have been largely due to a loose/worn drive wheel connector (see Pulsar Dome - Loose Rotation Drive Whee, 2023-10-27 ) which was fixed in mid November 2023 (see Pulsar Dome - Replacement Rotation Drive Wheel, 2023-11-17).  After the fix and after good slewing performance in subsequent daytime tests and during the S1168 session ( though the number of slews made in the live session, only 7 , was relatively few ) the new problems in the S1169 session came as both a surprise and a disappointment.

During a visit to the Observatory the following morning, it was noted that the dome wouldn't slew clockwise or anticlockwise from its position at Az 168, unless manual assistance was given to the help push the dome.   Examining the roof flange it was clear that the inner drive wheel had worn a hole in the anti-slip tape that is stuck to the inner surface of the roof flange. Probably assisted by grit eroded from the anti-slip tape the wheel had also worn away the several layers of paint on the roof flange and worn right down to the fibreglass, creating a 'well' that the dome couldn't be driven out of.  The slew records indicate that the drive wheel were spinning on this one spot for a total of nearly 10 minutes, easily explaining the extent of wear.  A small wear patch on the anti-slip tape was noted at position corresponding to the hold up at Az 258°.

Wear in Anti-Slip Tape and Underlying Paint caused by Drive Wheel spinning at the same spot for a total of 10 minutes over course of 3 slews Az 168° hold-up point		Wear to Anti-Slip Tape caused by Drive Wheel spinning at the same spot for a 3 minutes Az 258° hold-up point

It is possible that the Drive Wheel Tension is too great and isn't allowing the roof flange to move through the drive wheel system (two wheels on outside, one wheel on inside).  but this wasn't evident from examination of the drive wheel.

The anti-slip tape was applied to the roof flange in late October in an attempt to resolve the drive wheel slipping issue before it was determined that the issue was a loose/worn drive wheel connector, that caused the wheel to spin on its motor shaft rather than drive the roof flange around. With the fix now made to the replace the loose drive wheel and with the anti-slip tape compromised with wear divot it was decided to remove the anti-slip tape.  This was a relatively easy task to remove

It is noted that the angular difference between hold-up points at Az 168° and Az 258° is exactly 90°.  Now it unlikely to just be a coincidence that this anagle of 90 deg is also the angle separation between junctions in the observatory wall segments or between junctions in the roof flange. The hold-up of 168° corresponds to a position where one end of the rubbber trip can potentially touch against the protruding flanges where two wall segments abutt each other in the SW direction. This marks a 10 cm break in the rubber trim which has recently been filled with a 10 cm filler section of rubber trim in recent days. Due to the way the roof runs, which depends on the outline of the walls, and the position of 8 horizontal guide wheels in the top rim of the walls, the rubber trim on the roof flange comes very close and can rub against 3 out of the 4 junctions between wall segments. The protusion of wall flanges is made worse because one wall segment can have a wider flange than the adjacent section.    What ever the reason it is likely that hold-up or a general friction rubbing of rubber trim compromises the smooth rotation of the dome.

Close Juxtaposition of rubber trim/roof flange and the Wall Flange(s) (NW)  (indicated by red arrow)		Close Juxtaposition of rubber trim/roof flange and the Wall Flange(s) (SW)  (indicated by red arrow)	Likely Cause of Hold-Up at Az 168°  (indicated by red arrow)
Close Juxtaposition of rubber trim/roof flange and the Wall Flange(s) (NE)  (indicated by red arrow)		Close Juxtaposition of rubber trim/roof flange and the Roof 'Clamp' (SE)  (indicated by red arrow) here there's plenty of gap from wall flange

 

Fix (2023-12-01)

1.  The Anti-Slip Tap was removed as it is did prevent the current issue and it would be a future hinderance to smooth dome motion now that a divot has been worn into it.

2. The wall flanges adjacent to the rubber trim/roof flange were filed back by some 3mm or so using a metal file.

3. Drive Wheel tension was adjusted  

After doing this the motion of the dome was noticeably a lot smoother. 

Ideally these tasks should have been followed by a new DomeCalibration, this recalibration was eventually conducted 2023-12-02, see  Pulsar Dome - Recalibration 2023-12-02), after dome lost 9.6 deg of Az accuracy of the course of the session.

Filing Wall Flange (SW) back using a metal file This was the point associated with Az 168° hold-up		View Wall Flange (SW) after filing it back by 3 mm.

Update 2023-12-01

The following session (S1170, 2023-12-01) demonstrated that dome slewing performance was very good. None of the 56 slews during the session had any hold-ups or delays of any significance. The total delay across the whole session was just 0.4 minutes.

Dome Slewing Performance from S1170 session (post-fix, left) is compared below with the earlier poor performance from the S1168 session (right)

  

Issue fixed  2023-12-01 (Pulsar Dome)

Back to Top

AllSky Camera  - Latest Modification to Control Dew

• 
  

View of Top of AllSky Camera showing last attempt to control water entry/dew issues use an extra O-Ring worked for 4 days, then dew again.		View of Top of AllSky Camera showing single piece of original velcro (originally there were 4 pieces that were apparently designed to provide an air gap to allow ventilation of the hemisphere
View of Top of AllSky Camera showing latest modification to control dew which is to reinstate an air / ventalation gap between hemisphere and exterior. 4 small pieces of rubber draught excluder are used		View of AllSky Camera after refitting hemisphere

Update 2023-12-03

Back to Top