David's Astronomy Pages Notes - Session 666 (2019-02-21)

Notes (S665)

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Notes (S667)

	Session Aims & Highlights
	- Observing Result  - Session Event Log  - Night Summary Plot
	Operational Issues
	- Critical Issues (0),  Major Issues (2),  Minor Issues (4),  Continuous Improvement (5)
	Investigation - Drift in Focus Position (movement of the LX200's Main Mirror ?)
	Images from 2019-02-21  >>

Session Aims & Highlights (2019-02-21)

Main aims

1. Variable Stars Project - Continue acquire  light curve data from selected  variables over the course of a few hours with aim of detecting variation associated with eclipsing binary stars , RR Lyr stars and dwarf novae
2. Software & Systems  - Check stability of software and presence of any side effects following changes to AstroMain/AstroPlan to avoid slewing beyond 340/342°.

Equipment & Software

• 12" LX200 and ST-10XME
•  80mm APO and ZWO ASI 178MC
•  CCDApp2, TheSky6, CCDSoft5, PHD2,  POTH Hub
•  Pegasus UPB & Motor Focus, TCF-S
   
•  AstroMain 3.9.3,  AstroPlan 1.8

Highlights

• Azmiuth Checking shown to be now working corrrectly, by stopping a slew to target 6 (GCVS TV Cas) at 358.8°.

Lowlights

• Poor sky conditions

Summary Plots & Logs

Observing Plan (2019-02-21, S666)

Observing Result (2019-02-21, S666)

Night Sky Summary Plot - 2019-02-21, S666 Top axis: Sky Brightness at Zenith (in ADU/s) Lefthand axis: Local Time (hh LT). Righthand axis: Sun Altitude (degs)

Session Event Log (2019-02-21, S666)

Time   Event Detail 01:40 Session Created Live Session Created (2019-02-21 S00666, ImageSaveNum: 666001) 01:42 Obs.Manager Started Obs.Manager started 01:42 Services Started Observatory Services started 01:42   Camera1 Connected SBIG Camera Connected (set point -20°C) 01:43 Observatory (Auto) Observatory placed in Fully-Automated Mode 01:43 Session Pending Session pending (2019-02-21) 01:43 Session Initiating Session initiating (2019-02-21) 01:43   Plan Loaded Observing Plan loaded to queue (2019-02-21 V7 CYCLE PLAN, Plan ID: 289) 01:43   Camera1 Connected SBIG Camera Connected (set point -20°C) 01:43   Telescope Connected Telescope Connected (TheSky6) 01:44 Shutter Opened Shutter opened (opening time 45s) 01:44 Equilibration Started Dome Equilibration started 01:48 Equilibration Ended Dome Equilibration ended (4.0 mins total) 01:48 Session Running Session running 01:48   Queue Started Observing Queue started (27 targets selected) 01:48     Target Missed (1/27) Target Missed (1/27, GCVS RZ LMi) 01:48     Target Missed (2/27) Target Missed (2/27, GCVS ER UMa) 01:48     Target Started (3/27) Target started (3/27, GCVS RR Leo) 01:52   Focusing Started (Foc1) Foc1 Focusing Started (TCF-S) 01:56     Target Completed Target partially completed (3/27, GCVS RR Leo) 01:56     Target Started (4/27) Target started (4/27, GCVS RZ LMi) 01:59   Focusing Started (Foc1) Foc1 Focusing Started (TCF-S) 02:03   Focusing Completed Foc1 AutoFocus Completed (Profile No 1) 02:07     Target Completed Target partially completed (4/27, GCVS RZ LMi) 02:07     Target Started (5/27) Target started (5/27, GCVS ER UMa) 02:12     Target Completed Target completed (5/27, GCVS ER UMa) 02:13     Target Started (6/27) Target started (6/27, GCVS TV Cas) 02:20     Target Started (7/27) Target started (7/27, GCVS RR Leo) 02:30     Target Completed Target completed (7/27, GCVS RR Leo) 02:30     Target Started (8/27) Target started (8/27, GCVS RZ LMi) 02:39     Target Completed Target completed (8/27, GCVS RZ LMi) 02:41     Target Started (9/27) Target started (9/27, GCVS ER UMa) 02:48     Target Completed Target completed (9/27, GCVS ER UMa) 02:51     Target Started (10/27) Target started (10/27, GCVS TV Cas) 02:57     Target Completed Target completed (10/27, GCVS TV Cas) 02:58     Target Started (11/27) Target started (11/27, GCVS RR Leo) 03:08     Target Completed Target completed (11/27, GCVS RR Leo) 03:09     Target Started (12/27) Target started (12/27, GCVS RZ LMi) 03:18     Target Completed Target completed (12/27, GCVS RZ LMi) 03:20     Target Started (13/27) Target started (13/27, GCVS ER UMa) 03:27     Target Completed Target completed (13/27, GCVS ER UMa) 03:30     Target Started (14/27) Target started (14/27, GCVS TV Cas) 03:36     Target Completed Target completed (14/27, GCVS TV Cas) 03:37     Target Started (15/27) Target started (15/27, GCVS RR Leo) 03:47     Target Completed Target completed (15/27, GCVS RR Leo) 03:48     Target Started (16/27) Target started (16/27, GCVS RZ LMi) 03:56 Critical Conditions Alert Critical Conditions Alert (Obs.Manager will close the Shutter 03:56     Target Aborted (16/27) Target aborted (16/27, GCVS RZ LMi) due to other condition 03:56 Session Suspended Session suspended 03:57 Shutter Closed Shutter closed (closing time 48s) 03:58 Session Resuming Session resuming 03:59 Shutter Opened Shutter opened (opening time 45s) 03:59 Queue Resumed Observing Queue resumed 03:59     Target Started (17/27) Target started (17/27, GCVS ER UMa) 04:11     Target Completed Target completed (17/27, GCVS ER UMa) 04:11     Target Started (18/27) Target started (18/27, GCVS TV Cas) 04:17     Target Completed Target completed (18/27, GCVS TV Cas) 04:17     Target Started (19/27) Target started (19/27, GCVS RR Leo) 04:28     Target Completed Target completed (19/27, GCVS RR Leo) 04:28     Target Started (20/27) Target started (20/27, GCVS RZ LMi) 04:37     Target Completed Target completed (20/27, GCVS RZ LMi) 04:38     Target Started (21/27) Target started (21/27, GCVS ER UMa) 04:44     Target Completed Target completed (21/27, GCVS ER UMa) 04:47     Target Started (22/27) Target started (22/27, GCVS TV Cas) 04:53     Target Completed Target completed (22/27, GCVS TV Cas) 04:54     Target Started (23/27) Target started (23/27, GCVS RR Leo) 05:04     Target Completed Target completed (23/27, GCVS RR Leo) 05:05     Target Started (24/27) Target started (24/27, GCVS RZ LMi) 05:14     Target Completed Target completed (24/27, GCVS RZ LMi) 05:16     Target Started (25/27) Target started (25/27, GCVS ER UMa) 05:23     Target Completed Target completed (25/27, GCVS ER UMa) 05:26     Target Started (26/27) Target started (26/27, GCVS TV Cas) 05:31     Target Completed Target completed (26/27, GCVS TV Cas) 05:33     Target Started (27/27) Target started (27/27, GCVS RR Leo) 05:42     Target Completed Target completed (27/27, GCVS RR Leo) 05:43 Queue Completed Job Queue completed 05:43 Session Closing Session closing 05:43 Shutter Closed Shutter closed (closing time 50s) 05:45 Dome Parked Dome parked (parking time 78s) 05:46 Telescope Parked Telescope parked (parking time 42s) 05:47 Session Finished Session Finished

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Operational Issues (2019-02-21, S666)

• Critical Issues (0)
• Major Issues (2)
  
• Minor issues (4)
• Continuous Improvement (5)

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Critical Issues

• None

Major Issues

• Session not being suspended in conditions with significant amount of high cloud.  Similar to sessions on 2019-02-07 and 2019-02-06 , With Cloud Cover at 80%+, AllSkyStars Count of <8  and locate images failing to link, the Session should have suspended even though Clarity was still up around 38.  The cloud sensor has difficulty detecting high cloud which is inherently cold.  Session suspension in this case is not for the normal reason of preventing the damaging impact of any upcoming rain , but to reduce the amount of non-useful data and reduce unnecessory wear & tear of the telescope.  Need to obviously avoid the shutter getting into wasteful close/open/close/open loops.  Issue is raised from Minor to Major due to it's frequency of occurance.Resolved by using Supend when Too Few Stars option (where a Threshold no. of AllSky Stars is used to inform Session Suspension
    Resolved (Data unknown)  (AstroMain v???) 
   
• Drift in Focus Position, possibly caused by movement of the LX200's Main Mirror   After allowing for temperature related changes, the position of best focus recorded using TCF-S Focuser has seems to have reduced over the course of several months and now sits at around 750 out of the 0-7000 range on the TCF-S focuser). Things have reached the point that main mirror needs to be refocused at  around 3500 step position.   Investigation has been conducted which confirms that percieved focus drift is real See Graph / Investigation.   Main Mirror Lock was checked (it was tight and could only be loosened by turning the main focus knob
  Main Mirror focus was positioning close at midway position of the TCF-S focuers and then locked down.  

Minor issues

• Pulse Commands from PHD2 to LX200 Mount failed causing guiding to be ineffective.  Whilst activating autoguiding on first two targets of the Session,  3/27 (GCVS RR Leo) and 4/27 (GCVS RZ LMi),  the following error was reported multiple (28)  times.
      Unknown Event ...         Info      Event : Alert
      Unknown Event ...         Info      Event : Alert
  On the next target (5/27, GCVS ER UMa) the following errors appeared whilst starting Autoguiding.
      Unknown Event ...         Info      Event : CalibrationFailed
      Unknown Event ...         Info      Event : GuidingStopped
  It was noticed from the PHD2 history window that RA errors were unexpectedly large and that no pulse commands seemed to issued in either RA and Dec directions.   An error message also appeared  saying that "PulseGuide command to mount has failed - guiding is likely to be ineffective".   (see Fig 1)Problem was solved by stopping and restarting PHD2 (the problem could have been classed as major if it hadn't been spotted and resolved over a remote connection)
    Closed but monitor future sessions for any re-occurence
   
• Time slot for Target 6 (GCVS TV Cas) was wasted as the target sat beyond the safe Az.Limit (342°) and was rejected by azimuth checking.  At the MidTime of the target (and based on Planned Start Time of 02:18) the target sat slightly west of North (say Az 001°),  however the Azimuth Checking uses the StartTime of the target and is based on a time which is up to 5 minutes before the Planned Start Time.  In the case of the target 6 it was still sitting at Azmiuth 358.8° when checked
    Fixed 2019-02-22 (AstroPlan 1.8.1. Fitness Checker modified to only allow accept a target observation where the azimuth at both the the earliest start time and at the planned end time are safely outside of the 340-360° azimuthal zone.
   
• Observatory Manager closed the Shutter at 03:36 due to 'Critical Conditions' but without a statement on the precise reason.  RZ LMi was aborted with the reason 'due to other condition'. Neither message is helpful for a post session review.  Extra code was added to try to either resolve issue / understand the problem better.
    Believed to be resolved (>> monitor for any further occurances).
    
• AstroMain ran into problems the following evening after automatically starting a new session when it froze and stopped responding whilst trying to unpark the scope .  This was something it couldn't do as power to the scope had been deliberately turned off after the session. Can't rule out that the program  stopped responding totally because of user interaction with the form.  Considered to be fixed in AstroMain 3.38 following major re-factoring to provide greater isolation of the UI Thread from the business code.  Deemed fixed by tests during the final part of session S867 (2021-03-05).
  Resolved 2021-03-06 (AstroMain 3.38)

Continuous Improvement

• Add new open folder button to AstroMove / 'MoveFromObservatory' tab called  'New Session Logs' .  The new button and associated routine will enable faster access to the data just moved.
    Done 2019-02-22  (AstroMove 1.2.6)
   
• Add new launch button to AstroLaunch to Analysis Tab, to open PaintShopPro 
    Done 2019-02-22 (AstroLaunch 1.3.1 )
   
• Remove unnecessary buttons /code from AstroMain which are no longer serve a purpose. Examples are 'Employ Masters', 'Emply Next' on Reduction Tab, as they are now totally superceeded by Process All routine
    Done 2019-02-22 (AstroMain 3.9.4 )
   
• Add extra space lines before Centering, Autoguiding Subtitles in AstroMain / Target Executor
    Done 2019-02-22 (AstroMain 3.9.4 )
   
• Add special handling to support "Fast-Reaction ToO targets". This is to support new GRB detection project
    Done 2019-02-22 (AstroMain 3.9.4, AstroVoe 1.1, AstroPlan 1.8.1 )

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Fig 1

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Investigation - Drift in Focus Position  (movement of the LX200's Main Mirror ?)

After allowing for temperature related changes, the position of best focus recorded using TCF-S Focuser has seems to have reduced over the course of several months and now sits at around 750 out of the 0-7000 range on the TCF-S focuser). This may be partly gradual or seaonal, but it appears to be associated with a some more more definate jumps in position. See graph below.

Things have reached the point that main mirror needs to be refocused at  around 3500 step position.

Whilst some of the change might have occured when Imaging train was removed to dry out condensation in the OTA, it is wondered if the main mirror has not been properly locked down and has moved.

Actions

>> Check Main Mirror Lock (is it loose and thus probably responsible for the focus drift ?).
 
>> Refocus the Main Mirror at midway position of the TCF-S focuers and ensure it is locked down.  
     (It may be appropriate to coordinate this with the planned activity to replace the C Filter and take out the AO-8 unit)

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