David's Astronomy Pages Notes - Session 814 (2020-09-28)

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Notes (S815)

	Session Aims & Highlights
	- Observing Result  - Night Summary Plot  - Session Event Log
	Operational Issues
	- Critical Issues (0),  Major Issues (4),  Minor Issues (8),  Continuous Improvement (2)
	Images from 2020-09-28 >>
	Foc2 Focusing Problem (S813 & S814)
	- TS80 / Foc2 Focus Repair (2020-10-02)

Session Aims & Highlights (2020-09-28)

Main aims

1. Targets. Acquire images of a selection of deep sky targets
2. StartingMins. Test new 'Earliest Queue Start Time' functionality which involves calculating and passing StartingMins from AstroMain to AstroPlan so that Plan Start Time is defined at a point when observatory will be ready and resolve the recent issue that 1st target is being missed. See Earliest Plan Start Time

Equipment & Software

• 12" LX200 and ST-10XME
• 80mm APO and ZWO ASI 178MC
• CCDApp2, TheSky6, CCDSoft5, PHD2,  DeviceHub 4.6.1.11, UPB 1.5 
• Pegasus UPB & Motor Focus, TCF-S
• SharpCap 3.2, PHD2  2.6.9
   
• AstroMain 3.29.3,  AstroGuard 1.4.3,   AstroPlan 1.16.2,  AstroShCap 1.2.26, AstroVOE 1.3.6, AstroProtect 1.4.1
  (AstroWeather 1.10.13, AstroAllSky 3.6)
  

• Targets. x targets were imaged despite 2 incidences where DeviceHub.Dome stalled.

Lowlights

• Dome Connection. Dome Data supplied through DeviceHub.Dome stopped refreshing at 22:49 and again at 04:57

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)

Pre-Session Weather Forecast (API data from darksky.net) Pre-Session Weather forecast showed dry and clear conditons for the entire night ( 0-16% cloud cover) with temperature falling to minimum temperature of 8 °C by dawn but fairly windy (22mph dropping to 14mph by dawn) In the event conditions were dry but with a lot of fast moving cloud causing problems for imaging and guiding.  Wind was moderate for most of the night and temperatures were around 8°C (min).

Session Event Log

Time     Event Detail 21:59:59 Session Monitoring AutoStart monitoring for Live Session opportunity starting between 21:59 & 05:14 22:00:30 Session Created Live Session Created (2020-09-28 S00814, ImageSaveNum: 814001) 22:00:33   Scope Switched On Telescope Power has been switched on via UPB Powerbox. 22:02:23   Services Started Observatory Services started 22:02:32 Observatory (Auto) Observatory placed in Fully-Automated Mode 22:02:34 Session Pending Session pending (2020-09-28) 22:02:36 Session Initiating Session initiating (2020-09-28) 22:02:38   Plan Requested Observing Plan requested from AstroPlan (1.16.2) 22:03:35   Plan Loaded Observing Plan loaded to queue (2020-09-28 V1 BEST PLAN, Plan ID: 549) 22:03:47   Camera1 Connected SBIG Camera Connected (set point -15°C) 22:03:53   Telescope Connected Telescope Connected (TheSky6) 22:04:04 Session Equilibration Session ready for dome & camera equilibration 22:04:07   Equilibration Started Dome Equilibration started 22:09:36   Equilibration Ended Dome Equilibration ended (5.5 mins total) 22:09:38 Session Running Session running 22:09:40   Queue Started Observing Queue started (32 targets selected) 22:11:10       Focusing Started-Foc1 Foc1 Focusing Started (TCF-S) 22:16:42       Focusing Completed Foc1 AutoFocus Completed (Profile No 1) 22:18:06   SoftSuspend Called Soft Suspend is called due to Deteriorating Conditions (too few stars) 22:19:33       Focusing Failed Foc1 Focusing Failed - failed QC check (Ambiguous) 22:19:36       Focusing Started-Foc2 Foc2 Focusing Started (Secondary Scope, using ShCap) 22:19:48   Queue Paused Queue paused for SoftSuspend 22:19:52 Session Suspended Session suspended 22:20:17 Critical Cloud Alert Critical Cloud Alert (Obs.Manager will close the Shutter) 22:21:37   Dome Closed Dome closed (closing time 80s) 22:22:07   Dome Closed Dome closed (closing time 5s) 22:23:47   Dome Closed Dome closed (closing time 5s) 22:23:57 Session Resuming Session resuming 22:24:07   Dome Opened Dome opened (opening time 10s) 22:24:09 Session Running Session running 22:24:11   Queue Resumed Observing Queue resumed 22:24:13     Target Started (1/32) Target started (1/32, GCVS S Cyg) 22:27:06       Focusing Started-Foc1 Foc1 Focusing Started (TCF-S) 22:32:15       Focusing Completed Foc1 AutoFocus Completed (Profile No 2) 22:35:01       Focusing Completed Foc1 AutoFocus Completed (Profile No 2) 22:41:08     Target Completed Target partially completed (1/32, GCVS S Cyg) 22:41:11     Target Started (2/32) Target started (2/32, NGC 7722) 22:44:16       Focusing Failed Foc1 Focusing Failed - star is too dim (TCF-S) 22:57:01     Target Completed Target completed (2/32, NGC 7722) 22:57:03     Target Started (3/32) Target started (3/32, WDS GRB 34) 22:59:36       Focusing Started-Foc1 Foc1 Focusing Started (TCF-S) 23:02:33       Focusing Completed Foc1 AutoFocus Completed (Profile No 3) 23:04:43     Target Completed Target completed (3/32, WDS GRB 34) 23:04:45     Target Started (4/32) Target started (4/32, GSC 1224:29) 23:06:11     Target Failed Target failed due to centering error (4/32, GSC 1224:29) 23:06:13   Queue Aborted Job Queue aborted 23:07:14   Telescope Parked Telescope parked (parking time 35s) 23:07:44   Telescope Switched Off Telescope Power has been switched off via UPB Powerbox. 23:09:42   Services Stopped Observatory Services stopped 23:10:41 Program Closed Program closed by User 23:10:43 Program Closed Program closed by User 23:12:05 Session Resumed Live Session Resumed (2020-09-28 S00814, ImageSaveNum: 814026) 23:12:20   Obs.Manager Started Obs.Manager started 23:12:22   Obs.Overseer Started Obs.Overseer started 23:12:26   Services Started Observatory Services started 23:12:39   Scope Switched On Telescope Power has been switched on via UPB Powerbox. 23:14:18   Services Started Observatory Services started 23:15:49   Camera1 Connected SBIG Camera Connected (set point -15°C) 23:15:56   Telescope Connected Telescope Connected (TheSky6) 23:17:18       Focusing Started-Foc2 Foc2 Focusing Started (Secondary Scope, using ShCap) 23:19:03       Focusing Started-Foc2 Foc2 Focusing Started (Secondary Scope, using ShCap) 23:22:15       Focusing Aborted Foc2 Focusing Aborted 23:22:52       Focusing Started-Foc2 Foc2 Focusing Started (Secondary Scope, using ShCap) 23:26:08       Focusing Completed Foc2 AutoFocus Completed (Profile No 6, wide) 23:28:29       Focusing Failed Foc2 Focusing Failed - failed QC check (Quadratic) 23:28:49       Focusing Started-Foc2 Foc2 Focusing Started (Secondary Scope, using ShCap) 23:31:25       Focusing Failed Foc2 Focusing Failed - failed QC check (Quadratic) 23:32:01       Focusing Started-Foc2 Foc2 Focusing Started (Secondary Scope, using ShCap) 23:34:34       Focusing Failed Foc2 Focusing Failed - failed QC check (Range) 23:34:56       Focusing Started-Foc2 Foc2 Focusing Started (Secondary Scope, using ShCap) 23:37:18       Focusing Aborted Foc2 Focusing Aborted 23:37:30       Focusing Started-Foc2 Foc2 Focusing Started (Secondary Scope, using ShCap) 23:41:19       Focusing Aborted Foc2 Focusing Aborted 23:41:40       Focusing Started-Foc2 Foc2 Focusing Started (Secondary Scope, using ShCap) 23:44:14       Focusing Aborted Foc2 Focusing Aborted 23:44:22       Focusing Started-Foc2 Foc2 Focusing Started (Secondary Scope, using ShCap) 23:47:17       Focusing Completed Foc2 AutoFocus Completed (Profile No 9, wide) 23:49:22       Focusing Failed Foc2 Focusing Failed - failed QC check (Range) 23:49:46   Services Started Observatory Services started 00:17:24       Focusing Started-Foc2 Foc2 Focusing Started (Secondary Scope, using ShCap) 00:18:41       Focusing Aborted Foc2 Focusing Aborted 00:19:06       Focusing Started-Foc2 Foc2 Focusing Started (Secondary Scope, using ShCap) 00:21:31       Focusing Failed Foc2 Focusing Failed - failed QC check (Quadratic) 00:22:17 Observatory (Auto) Observatory placed in Fully-Automated Mode 00:22:18 Session Pending Session pending (2020-09-28) 00:22:20 Session Initiating Session initiating (2020-09-28) 00:22:22   Plan Loaded Observing Plan loaded to queue (2020-09-28 V1 ACTIVE PLAN S814, Plan ID: 549) 00:22:23   Camera1 Connected SBIG Camera Connected (set point -20°C) 00:22:27   Telescope Connected Telescope Connected (TheSky6) 00:22:39 Session Equilibration Session ready for dome & camera equilibration 00:22:42   Equilibration Started Dome Equilibration started 00:22:44   Equilibration Skipped Dome Equilibration skipped by user 00:22:46 Session Running Session running 00:22:48   Queue Started Observing Queue started (28 targets selected) 00:23:14     Target Missed (5/32) Target's time slot was missed (5/32, GCVS RX And) 00:23:16     Target Missed (6/32) Target's time slot was missed (6/32, 61 Cyg) 00:23:18     Target Missed (7/32) Target's time slot was missed (7/32, C/2020 Q1 (Borisov)) 00:23:20     Target Missed (8/32) Target's time slot was missed (8/32, GCVS Z And) 00:23:22     Target Missed (9/32) Target's time slot was missed (9/32, GCVS U And) 00:23:24     Target Missed (10/32) Target's time slot was missed (10/32, GCVS TT Ari) 00:23:26     Target Started (11/32) Target started (11/32, 11P/Tempel-Swift-LINEAR) 00:23:28     Target Failed Target failed due to target not found (11/32, 11P/Tempel-Swift-LINEAR) 00:38:00     Target Started (12/32) Target started (12/32, GCVS HH And) 00:40:07       Focusing Started-Foc1 Foc1 Focusing Started (TCF-S) 00:42:57       Focusing Completed Foc1 AutoFocus Completed (Profile No 12) 00:44:41     Target Completed Target completed (12/32, GCVS HH And) 00:46:16     Target Started (13/32) Target started (13/32, GCVS SS Cyg) 00:48:07       Focusing Started-Foc1 Foc1 Focusing Started (TCF-S) 00:50:48       Focusing Completed Foc1 AutoFocus Completed (Profile No 13) 00:54:30     Target Completed Target completed (13/32, GCVS SS Cyg) 01:01:27     Target Started (14/32) Target started (14/32, GCVS BL Lac) 01:03:08       Focusing Started-Foc1 Foc1 Focusing Started (TCF-S) 01:05:56       Focusing Completed Foc1 AutoFocus Completed (Profile No 14) 01:09:28     Target Completed Target completed (14/32, GCVS BL Lac) 01:11:45     Target Started (15/32) Target started (15/32, Berkeley 72) 01:15:40       Focusing Started-Foc1 Foc1 Focusing Started (TCF-S) 01:18:42       Focusing Completed Foc1 AutoFocus Completed (Profile No 15) 01:25:03     Target Completed Target completed (15/32, Berkeley 72) 01:25:06     Target Started (16/32) Target started (16/32, NGC 2158) 01:26:53       Focusing Started-Foc1 Foc1 Focusing Started (TCF-S) 01:29:57       Focusing Failed Foc1 Focusing Failed - failed QC check (Ambiguous) 02:07:30     Target Completed Target partially completed (16/32, NGC 2158) 02:07:32     Target Started (17/32) Target started (17/32, GCVS AM Her) 02:10:39       Focusing Started-Foc1 Foc1 Focusing Started (TCF-S) 02:13:31       Focusing Completed Foc1 AutoFocus Completed (Profile No 17) 02:18:24     Target Completed Target completed (17/32, GCVS AM Her) 02:18:26     Target Started (18/32) Target started (18/32, GCVS CI Cyg) 02:21:04       Focusing Started-Foc1 Foc1 Focusing Started (TCF-S) 02:23:53       Focusing Completed Foc1 AutoFocus Completed (Profile No 18) 02:27:29     Target Completed Target completed (18/32, GCVS CI Cyg) 02:27:31     Target Started (19/32) Target started (19/32, GCVS DY Per) 02:30:21       Focusing Started-Foc1 Foc1 Focusing Started (TCF-S) 02:33:13       Focusing Completed Foc1 AutoFocus Completed (Profile No 19) 02:37:34     Target Completed Target completed (19/32, GCVS DY Per) 02:37:36     Target Started (20/32) Target started (20/32, GCVS CM Tau) 02:39:47       Focusing Started-Foc1 Foc1 Focusing Started (TCF-S) 02:42:45       Focusing Completed Foc1 AutoFocus Completed (Profile No 20) 02:57:17     Target Completed Target completed (20/32, GCVS CM Tau) 02:57:20     Target Started (21/32) Target started (21/32, GCVS RR Tau) 02:59:46       Focusing Started-Foc1 Foc1 Focusing Started (TCF-S) 03:02:35       Focusing Completed Foc1 AutoFocus Completed (Profile No 21) 03:08:31     Target Completed Target completed (21/32, GCVS RR Tau) 03:08:33     Target Started (22/32) Target started (22/32, C/2019 L3 (ATLAS)) 03:11:58       Focusing Started-Foc1 Foc1 Focusing Started (TCF-S) 03:14:49       Focusing Completed Foc1 AutoFocus Completed (Profile No 22) 03:21:27     Target Completed Target completed (22/32, C/2019 L3 (ATLAS)) 03:21:29     Target Started (23/32) Target started (23/32, GCVS GK Per) 03:24:19       Focusing Started-Foc1 Foc1 Focusing Started (TCF-S) 03:27:10       Focusing Completed Foc1 AutoFocus Completed (Profile No 23) 03:30:07     Target Completed Target completed (23/32, GCVS GK Per) 03:30:09     Target Started (24/32) Target started (24/32, GCVS FU Ori) 03:32:15       Focusing Started-Foc1 Foc1 Focusing Started (TCF-S) 03:35:24       Focusing Completed Foc1 AutoFocus Completed (Profile No 24) 03:37:58     Target Completed Target completed (24/32, GCVS FU Ori) 03:38:00     Target Started (25/32) Target started (25/32, C/2020 F8 (SWAN)) 03:40:32       Focusing Started-Foc1 Foc1 Focusing Started (TCF-S) 03:43:23       Focusing Completed Foc1 AutoFocus Completed (Profile No 25) 03:55:31     Target Completed Target partially completed (25/32, C/2020 F8 (SWAN)) 03:55:33     Target Started (26/32) Target started (26/32, NGC 2782) 03:58:22       Focusing Started-Foc1 Foc1 Focusing Started (TCF-S) 04:01:18       Focusing Completed Foc1 AutoFocus Completed (Profile No 26) 04:17:13     Target Completed Target completed (26/32, NGC 2782) 04:17:15     Target Started (27/32) Target started (27/32, UGC 6930) 04:20:06       Focusing Started-Foc1 Foc1 Focusing Started (TCF-S) 04:23:08       Focusing Completed Foc1 AutoFocus Completed (Profile No 27) 04:34:11     Target Completed Target completed (27/32, UGC 6930) 04:34:13     Target Started (28/32) Target started (28/32, UGC 4052) 04:37:15       Focusing Started-Foc1 Foc1 Focusing Started (TCF-S) 04:39:56       Focusing Completed Foc1 AutoFocus Completed (Profile No 28) 04:55:28     Target Completed Target completed (28/32, UGC 4052) 04:55:30     Target Started (29/32) Target started (29/32, UGC 4414) 04:58:01       Focusing Started-Foc1 Foc1 Focusing Started (TCF-S) 05:01:14       Focusing Completed Foc1 AutoFocus Completed (Profile No 29) 05:16:59     Target Completed Target completed (29/32, UGC 4414) 05:17:01     Target Started (30/32) Target started (30/32, GCVS DX Cnc) 05:18:59       Focusing Started-Foc1 Foc1 Focusing Started (TCF-S) 05:21:59       Focusing Completed Foc1 AutoFocus Completed (Profile No 30) 05:27:58     Target Completed Target completed (30/32, GCVS DX Cnc) 05:28:00     Target Started (31/32) Target started (31/32, GCVS NV Ori) 05:32:11       Focusing Failed Foc1 Focusing Failed - unable to find a star (TCF-S) 05:37:02     Target Failed Target failed due to Dome Issue (31/32, GCVS NV Ori) 05:37:04     Target Started (32/32) Target started (32/32, GCVS CN Ori) 05:41:27       Focusing Failed Foc1 Focusing Failed - unable to find a star (TCF-S) 05:46:45     Target Failed Target failed due to Dome Issue (32/32, GCVS CN Ori) 05:46:48   Queue Completed Job Queue completed 05:46:50 Session Closing Session closing 06:13:48 Observatory (Manual) Observatory placed in Manual Mode 06:18:29   Telescope Switched Off Telescope Power has been switched off via UPB Powerbox. 06:19:45   Camera1 Disconnected SBIG Camera closed down & disconnected 06:32:47   Dome Closed Dome closed (closing time 2,752s) 06:32:49 User Intervention User request to close and finish session 06:32:51 Session Closing Session closing 06:32:54   Dome Closed Dome closed (closing time 5s) 06:33:02   Dome Parked Dome parked (parking time 10s), Az: 90.0 deg 06:33:53   Services Stopped Night Services stopped 06:33:55 Session Housekeeping Housekeeping Started (Cleanup FITS, Create Fits Summary, Transfer Files) 06:34:47 Session Finished Session Finished

Session Alerts

Time     Alert Detail 00:22:46 Dome Alert DomeRecords have stopped updating 00:38:32 Dome Alert DomeRecords have resumed updating

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Operational Issues (2020-09-28 S814)

• Critical Issues (0)
• Major Issues (4)
• Minor Issues (8)
• Continuous Improvement (2)

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Critical Issues

•  None

Major Issues

• Dome was opened during Equilibration start or began to open but was immediately closed. After beginning session using AutoStart, the ObsPicture was notice to show an opening shutter, but it immediately returned to closed shutter state. DeviceHub reported that Dome was closed whilst it slew to its into Wind AZ position.  AstroGuard reports 22:06 Dome has opened (5s), 22:19 Dome has closed (47s), 22:23 Dome has opened (47s).  AstroMain logs suggest Shutter is already open  at 22:04.  This was due to a bug introduced in Dome.ShutterStatus Get routine in AstroMain 3.29.3 which was modified to throttle-back on calls to DeviceHub.Dome.
  Fixed 2020-09-29 (AstroMain 3.29.4).
   
• DeviceHub.Dome stalled whilst Taking Image 2/5 for Target  2/32 (NGC 7722)  at 22:49.   Similar symptoms to previous occurances of the issue.   DeviceHub stops getting fresh data from the the Dome (22:49:18), dome slaving stops working. Issue seen whilst monitoring the session remotely and intervention made to park scope and restart observatory software (including DeviceHub) and recontinue the session. 
  DeviceHub.Dome stalled Making Centering Correction following Locate Frame 2 for Target  29/32 (UGC 4414)  at 04:57.   Similar symptoms to previous occurances of the issue.   DeviceHub stops getting fresh data from the the Dome (04:57:04), dome slaving stopped working. Issue evident from blank frames captured for the last two targets of the session, where the dome roof occuluded the telescope's view of the night sky.   
  Both issues were 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 the first 8 sessions using the new DH version.  
  Closed 2020-11-06 (Device Hub 6.5.0.1).
   
• Foc 2 Focuser not moving TS80 telescope focus position. After problems with Foc2 focusing in the last session, some manually initiated attempts to refocus the TS80 scope where made.  It was concluded that Foc2 Focuser was not moving the telescope tube as focus / FWHM appeared to be varying with seeing and was not changing with Focuser Step position. This conclusion was reached after trying to create focus profiles via SharpCap and after watching a star profile in PHD2 whilst trying to move focus to different positions - the star remains largely unchanged in diameter and sharpness.   A visit to observatory seemed to confirm this (though daytime tests would be more definitive). Focusing performimg manually using focus knobs whilst watching star in PHD2.  Focuser position synced set to 8031 as it had reached 500.   On 2020-10-02 the TS80 scope was removed from top of main scope and without changing camera orientation and x/y position  the focusing system was examined.  The drawtube was at the 22mm position which corresponded to the position of best focus manually identified during session S814. Testing with cable connector to Focus Motor and UPB Focus Controller confirmed the diagnosis that the focus motor was running ok but it was not moving the scope's rail & pinion (RAP) focuser - the draw tube was not moving in or out.   After looking back at the installation notes made when focuser was installed (see Installation of Motor Focus Unit on TS80 secondary scope, 2018-11-07), the grub screw that were meant to firmly connect the 6mm coupler to the RAP's focus shaft was examined and found to be loose.  It was tightened up and the focuser system re-tested and shown to now be moving the draw tube correctly. The focuser was reset to 9000 at position and the TS Scope reattached to dovetail on top of the main scope and all cables reconnected.
  Fixed 2020-10-02 (Observatory / Foc2 Focuser).
   
• Obs.Manager froze whilst waiting for dome to close after commanding dome closure at 05:46. Obs.Overseer reported Obs.Manager was frozen at 05:47:08 following a command to close the Dome Shutter at 05:46:56 as part of closing the Session  Issue might have been caused as a consequence of a bug introduced in Dome.ShutterStatus Get routine in AstroMain 3.29.3 which was modified to throttle-back on calls to DeviceHub.Dome. Investigation needed to establish that Dome.ShutterStatus of 0 could cause the Obs.Manager to freeze or due to inability of DeviceHub.Dome.ShutterStatus to return 1 (Closed) due to Dome Data stalling at 04:57.  The Close command was communicated to the Dome at 05:46:56 and the the Dome Shutter did become closed at 05:47:40  (closing time 44s) -  the issue is therefore classified as a Major Issue rather than a Critical Issue.  Situation was overcome by setting Observatory Mode to Manual (06:13), by Parking Scope using DeviceHub.Telescope (06:15), turning off Telescope Power (06:18),  by Stopping Service in AstroGuard,   Stopping Hub Services (06:24),  Restarting Dome Service (06:32), Running Close/Finish Session, manual initiated (06:32).  An attempted fix has been written that utilises a Thread 'CloseShutterTask' that it is hoped will keep Obs.Manager from freezing. At a minimum it will help to better diagnose the problem better by use of debug tracing messages to logfile.
  Fixed 2020-09-30 (AstroMain 3.29.5)

Minor Issues

• Targets Database Transfer reported as 0001-01-01 00:00 rather than a proper date.  Issue reported before (date/session ?).   New Live Session               2020-09-28 22:00 (Local)
Session ID:               Ok   814 (Live)
Session Name:             Ok   2020-09-28 S00814 (Session)
Targets Database Transfer Ok   0001-01-01 00:00 (Local) Last Database Transfer To Observatory
Session.DatabaseTransferTime is reported in AssignObservatorySession() routine (Date was not the vcNullDate otherwise data would have been reported as 'Unknown Time'  but was the VB.net null date).   Session.DatabaseTransferTime should be set in CanProceedToCreateNewSession() routine where TransferTime is read from "C:\Data\CCD Imaging\Targets Database\Transfer-Record.dat" .   Checking showed that this file contained the Transfer time 2020-09-28 21:57:50  which corresponds precisely with the time Targets Database was uploaded to the Observatory Computer using AstroMove.  So why wasn't this the time reported.   It seems that CanProceedToCreateNewSession() routine (where DatabaseTransferTime is set) is only run when 'Create Live Session' (or Create Test Session) button and manually operated.   When AutoStart is used to create a live session, the CanProceedToCreateNewSession() routine is not accessed and therefore the DatabaseTransferTime is not set.
  Fixed 2020-09-29 (AstroMain 3.29.4).
   
• AstroMain produced 3 'Close Dome...' messages at 22:20 : Dome is Closed (80s), Dome is Closed (5s), Dome is Closed (5s).  In response to Critical Cloud Conditions at 22:20, Obs.Manager took action to close the dome shutter. It was surprising to see message lines 'Close Dome...' with different results. This is possibly due to a bug introduced in Dome.ShutterStatus Get routine in AstroMain 3.29.3 which was modified to throttle-back on calls to DeviceHub.Dome.
  Fixed 2020-09-29 (AstroMain 3.29.4).
   
• When Session Resumed at 22:23 the dome opening time (10s) was unexpectedly short. This is probably due to a bug introduced in Dome.ShutterStatus Get routine in AstroMain 3.29.3 which was modified to throttle-back on calls to DeviceHub.Dome.
  Fixed 2020-09-29 (AstroMain 3.29.4).
   
• Large Dome Discrepency reported following a slew to S Cyg (22:24). Following slew to Target 1/32 (S Cyg, Az 283.0 degs) the Dome az was reported as being 165.9 deg. This is a 117.3 degs difference from the scope.  Scope didn't appear to be occuled by dome roof, so slew must have occurred ok, which is confirmed also by ObsPic view at 22:26.  It would be helpful to post a followup Dome Az position at the end of Centering 1 (add ticket item for this).     Log file reports telescope slew took 31.5s , with dome slew 32.3s and overal slew 32.3s. The code from 'Dome.SlewTheSkyScope()' routine is unable to explain why  Dome.PostSlewAz = Dome.Azimuth at the end of slew  (32s after start) wasn't picking up a moved Dome Azimuth but was still showing the azimuth that the dome had before slewing started.  ObsPics help to explain what happened:
   ObsPic at 22:23:49 shows scope tracking at Az 163/Alt 81, Dome 'slaved' at Az 166, with Shutter apparently closed (but reported as open)
   ObsPic at 22:24:19 shows scope slewing at Az 283, Dome 'slewing' at Az 166, with Shutter apparently opening. 
   ObsPic at 22:24:49 shows scope tracking at Az 283, Dome 'slaved at Az 166, with Shutter open. 
   ObsPic at 22:25:22 shows scope 'slewing' at Az 283/Alt 76, Dome slewing at Az 250, with Shutter open. 
   ObsPic at 22:25:53 shows scope 'slewing' at Az 283/Alt 76, Dome slaved at Az 274, with Shutter open. 
  So it seems that dome opening (which set the Dome.Slewing = True) delayed the start of dome rotation and when opening stopped and Dome.Slewing temporarily went to False the SlewTheSkyScope() routine concluded the slew was completed.
  Observatory logs show that after S Cyg Target began 22:19 and whilst waiting for its time slot to start (22:26) there was a softsuspend / hardsuspend event at 22:20 and the session was suspended and the shutter closed. At 22:23 conditions improved and the session was resumed. The shutter was commanded to open, but after 10s and due to a bug in newly modified Dome.ShutterStatus Get routine the shutter was deemed to be open and the slew to S Cyg target begun before the shutter was fully open.  
  Closed 2020-10-03 (issue understood and the underlying cause was fixed 2020-09-29 (AstroMain 3.29.4).
   
• ObsPic show at 22:23:49 (S Cyg slew) show graphic with dome as apparently closed (about to start opening) but flag showed as Green / Dome is Open.
  Due to a bug in newly modified Dome.ShutterStatus Get routine  access to correct ShutterStatus values was compromised during this session and may have given rise to the issue seen.
  Closed 2020-10-03 (issue understood and the underlying cause was fixed 2020-09-29 (AstroMain 3.29.4).
   
• Telescope slew to S Cyg (22:24) was reported as taking 31s but log file suggests that slew had probably taken only 20.2s (or even only 15.9 -18s) . Logs show Angular Change of 0.0 at time steps 18.0s to 20s, but time step at 20.2s shows a further small change in position.   Log file reports telescope slew took 31.5s , with post slew az/alt with values equal to those at time 20.2s, so why is telescope slew time being overstated ?    Code fixed (the telescope slew time wasn't taking Last MovementTime into consideration when using DeviceHub).
  Fixed 2020-10-02 (AstroMain 3.30)
   
• Whilst daylight arrived AstroMain produced messages every 5s "Observatory Manager will close the Dome Shutter, Dome is Closed (5s)".  This was due to a bug introduced in Dome.ShutterStatus Get routine in AstroMain 3.29.3 which was modified to throttle-back on calls to DeviceHub.Dome.  Bug was causing ShutterStatus to return 0 (Open) when a call to ShutterStatus had previously been made in the previous 0.2s.   Bug seems to explain certain issues that arose during the night session.
  Fixed 2020-09-29 (AstroMain 3.29.4).
    
• Retake of 11P/Tempel-Swift-LINEAR starfield from earlier session (to check for moved object) failed with message "Object (Explicit Coords) not recognised."   This was due to target being flagged as a non-sidereal target, which would flag that coordinates needs to be looked up for 'Target Name or  for 'TheSky Name' where one is provided.  In this case TheSky Name was 'Explicit Coords' for which there is clearly no object to lookup.  User should really set target to be sidereal in cases where explicit coords are given.  This was a pretty unusual case.   Code could be modified ignore a 'non-sidereal' state where explicit coords are given as treat the target as Sidereal.  Ticket item added for this.
  Closed 2020-09-29 (User Awareness).

Continuous Improvement

• Non-Sidereal Target should be treated as a Sidereal Target where Explicit Coords are given.    This is to prevent a target (e.g. 11P/Tempel-Swift-LINEAR starfield retake) failing due to an oversight by the user.  AstroPlan should check for this condition and warn user before saving.  AstroMain should modify Sidereal state of such as target when loading plan.
  Done 2020-10-03 (AstroPlan 1.16.3, AstroMain 3.30)
   
• Add a Scope Az / Dome Az & Scope-Dome Az Difference / Discrepency alert at end of Centering 1 operation.    This is to help diagnosis of dome slew / dome azimuth reporting, where Dome Az doesn't always appear to be correct at end of a slew.   New routine written : Dome.CheckDomePosition() 
  Done 2020-10-03 (AstroMain 3.30)

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Foc2 Focusing Problem (S813 & S814)

After problems with Foc2 focusing in the last session (S813, 2020-09-26)  some manually initiated attempts to refocus the TS80 scope where made.  It was concluded that Foc2 Focuser was not moving the telescope tube as focus / FWHM appeared to be varying with seeing and was not changing with Focuser Step position. This conclusion was reached after trying to create focus profiles via SharpCap and after watching a star profile in PHD2 whilst trying to move focus to different positions - the star remains largely unchanged in diameter and sharpness.  

A visit to observatory seemed to confirm this (though daytime tests would be more definitive). Focusing was performed by manually using focus knobs whilst watching star in PHD2.  Focuser position synced set to 8031 as it had reached 500.   Normally the manual focusing knobs shouldn't be used when Motor Focus is attached because of possible damage it might cause to the motpr focus gears, however since the motor focus wasn't operating it was felt to be a risk that had to be taken.   (it later became evident that the motor focus had decoupled from the RAP focuser shaft explains why there was no resistance when focus knobs were manually turned and why autofocusing had stopped working)

Foc2 Focus profiles from Session S814, 2020-09-28 (non-working focuser) compared with Session S799, 2020-08-24  (working focuser)

Wide Focus profile (S814, Profile 6 Wide) Profile has picked point with random better seeing as rough 'best focus'

Standard Focus profile (S814, Profile 6) Profile shows no sharpening of focus across the position of rough 'best focus' from wide search Although the Focus Motor is stepping to different positions its not moving the drawtube and hence we can't see changes in focus quality with step position

Standard Focus profile (S814, Profile 11) After manually focusing used RAP coarse & fine focus knobs a new autofocus profile again shows the absence of any significant change in focus quality with focus step position profile is essentially flat with FWHM & HFD variations due to seeing / cloud

Initial Wide Profile for session where focuser was working correctly (Session 799, Profile 21) 'Best Focus' at 8771, based on the focus point with FWHM of 3.04 arc sec.

Detailed Focus Profile  for session where focuser was working correctly (Session 799, Profile 21) Focus Range :  8916 - 8626 (range: 290), centered on rough best focus from the 'Wide' Profile above 'Best Focus' at 8792, based on quadratic curve fit to the set of focus steps. Peak FWHM estimated to be 2.33 arc sec.

Focuser Repair (2020-10-02)

On 2020-10-02 the TS80 scope was removed from top of main scope and without changing camera orientation and x/y position  the focusing system was examined.  The drawtube was at the 22mm position which corresponded to the position of best focus manually identified during session S814. Testing with cable connector to Focus Motor and UPB Focus Controller confirmed the diagnosis that the focus motor was running ok but it was not moving the scope's rail & pinion (RAP) focuser - the draw tube was not moving in or out.  

After looking back at the installation notes made when focuser was installed (see Installation of Motor Focus Unit on TS80 secondary scope, 2018-11-07), the grub screw that were meant to firmly connect the 6mm coupling cylinder to the RAP's Focus Shaft was examined and found to be loose.  

The grub screw was tightened up and the focuser system re-tested and shown to now be moving the draw tube in and out correctly. The focuser was reset to 9000 at the prior best focus position (22mm drawtube position). Finally the TS Scope reattached to the dovetail on top of the main scope and all cables reconnected.

(Note: to access this grub screw the two grubs screws attaching the coupling cylinder to the motor focus shaft had to be temporarily loosened in order to turn the coupling cylinder into the necessary orientation to line up the grub screw with the hole used to access it)

6mm Coupling Cylinder showing the grub screw that was loose and required tightening (this was done with the motor focus in position, the photos is an earlier one for illustration only)		Motor Focus in position (photo is an earlier one and is for illustration only)

Whilst conducting this operation it was found that the drawtube could be moved a full 2mm before the resistance from the motor focus could be felt.  It's possible but not certain that this reflects the backlash in motor focus system.    Since the safe working range of the drawtube is 72mm (0.3 cm to 7.5cm from inner hard stop) which corresponds to 40000 motor focus steps, it would imply that the backlash is 1110 steps.   At present a backlash compensation of 4300 steps is used when focusing inward (focus step position).  Provided this figure is more than the actual backlash it doesn't impact quality of focusing, but does impact the time taken to move the focuser when moving inwards (but not outwards)

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