David's Astronomy Pages Notes - Session 791 (2020-06-10)

Notes (S790)

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Notes (S792)

	Session Aims & Highlights
	- Observing Result  - Night Summary Plot  - Session Event Log
	Operational Issues
	- Critical Issues (0),  Major Issues (0),  Minor Issues (9),  Continuous Improvement (3)
	Images from 2020-06-10 >>
	2020-06-22
	Wind Data Outage

Session Aims & Highlights (2020-06-10)

Main aims

1. DeviceHub: Carry out second live session using DeviceHub (new ASCOM replacement for POTH)
2. Southern Targets. Aquire targets low down in Summer Sky (Sagittarius) if conditions allowed

Equipment & Software

• 12" LX200 and ST-10XME
• 80mm APO and ZWO ASI 178MC
• CCDApp2, TheSky6, CCDSoft5, PHD2,  DeviceHub 4.6.1.10, UPB 1.5 
• Pegasus UPB & Motor Focus, TCF-S
• SharpCap 3.2, PHD2  2.6.8
   
• AstroMain 3.25.2,  AstroGuard 1.4.1,   AstroPlan 1.15.2,  AstroShCap 1.2.22, AstroVOE 1.3.6
  (AstroWeather 1.10.5, AstroAllSky 3.6)
  

Highlights

•   DeviceHub.  Second live session using DeviceHub. Hub / Dome / Scope worked well together.
•   Alerts System.  New system worked well to flag up an Sesion Alert (turned out to be a false alarm when investigated but it worked to highlight an important event)

Lowlights

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

Summary Plots & Logs

Observing Plan

Observing Result (Southern targets added as ToO targets)

Dome & Scope Slewing Performance

Slew/Centering Performance

Guiding Performance

Sky Conditions (Locate Frames)

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

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

Session Event Log

Time     Event Detail 23:10:11 Session Created Live Session Created (2020-06-10 S00791, ImageSaveNum: 791001) 23:10:54   Services Started Observatory Services started 23:11:04   Scope Switched On Telescope Power has been switched on via UPB Powerbox. 23:13:13   Services Started Observatory Services started 23:13:45   Camera1 Connected SBIG Camera Connected (set point -15°C) 23:14:01   Telescope Connected Telescope Connected (TheSky6) 23:14:52 Observatory (Auto) Observatory placed in Fully-Automated Mode 23:14:54 Session Pending Session pending (2020-06-10) 23:14:56 Session Initiating Session initiating (2020-06-10) 23:14:58   Plan Requested Observing Plan requested from AstroPlan (1.15.3) 23:15:49   Plan Loaded Observing Plan loaded to queue (2020-06-10 V1 BEST PLAN, Plan ID: 520) 23:15:53   Camera1 Connected SBIG Camera Connected (set point -15°C) 23:15:57   Telescope Connected Telescope Connected (TheSky6) 23:16:09 Session Equilibration Session ready for dome & camera equilibration 00:01:59   Dome Opened Dome opened (opening time 45s) 00:02:02   Equilibration Started Dome Equilibration started 00:15:15   Equilibration Ended Dome Equilibration ended (13.3 mins total) 00:15:17 Session Running Session running 00:15:19   Queue Started Observing Queue started (9 targets selected) 00:17:03       Focusing Started-Foc1 Foc1 Focusing Started (TCF-S) 00:19:52       Focusing Completed Foc1 AutoFocus Completed (Profile No 1) 00:19:54     Target Started (1/9) Target started (1/9, GCVS R CrB) 00:22:09       Focusing Started-Foc1 Foc1 Focusing Started (TCF-S) 00:24:48       Focusing Completed Foc1 AutoFocus Completed (Profile No 2) 00:27:43     Target Completed Target completed (1/9, GCVS R CrB) 00:27:45     Target Started (2/10) Target started (2/10, NGC 6401, ToO) 00:30:01       Focusing Started Foc2 Focusing Started (Secondary Scope, using ShCap) 00:31:19       Focusing Started-Foc1 Foc1 Focusing Started (TCF-S) 00:34:32       Focusing Completed Foc1 AutoFocus Completed (Profile No 3) 00:41:18     Target Completed Target completed (2/10, NGC 6401, ToO) 00:41:21     Target Started (3/11) Target started (3/11, NGC 6235, ToO) 00:53:58     Target Completed Target completed (3/11, NGC 6235, ToO) 00:54:01     Target Missed (4/11) Target's time slot was missed (4/11, GCVS U Her) 00:54:03     Target Missed (5/11) Target's time slot was missed (5/11, GCVS SS Her) 00:54:05     Target Missed (6/11) Target's time slot was missed (6/11, HIP 87937) 00:54:07     Target Started (7/11) Target started (7/11, GCVS AM Her) 00:54:09   SoftSuspend Called Soft Suspend is called due to Deteriorating Conditions (reducing clarity) 00:57:34     Target Failed Target failed due to cloud (7/11, GCVS AM Her) 00:57:36   Queue Paused Queue paused for SoftSuspend 00:57:38 Session Suspended Session suspended 00:58:24   Dome Closed Dome closed (closing time 49s) 01:13:07     Target Cancelled Target cancelled (8/11, GCVS CY Lyr) due to cloud 01:22:35     Target Cancelled Target cancelled (9/11, GCVS CI Cyg) due to cloud 01:29:52     Target Cancelled Target cancelled (10/11, 61 Cyg) due to cloud 01:54:51     Target Cancelled Target cancelled (11/11, GCVS SS Cyg) due to cloud 01:54:56   Queue Completed Job Queue completed 01:54:59 Session Closing Session closing 01:55:04   Dome Closed Dome already closed (closed at 00:58, closing time 49s) 01:57:21   Dome Parked Dome parked (parking time 136s) 01:58:17   Telescope Parked Telescope parked (parking time 50s) 01:58:47   Telescope Switched Off Telescope Power has been switched off via UPB Powerbox. 01:59:36   Services Stopped Night Services stopped 01:59:38 Session Housekeeping Housekeeping Started (Cleanup FITS, Create Fits Summary, Transfer Files) 01:59:40 Session Finished Session Finished

Session Alerts

Time     Alert Detail 01:58:17 Scope Failed To Park Correctly Telescope may have failed to park correctly

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Operational Issues (2020-06-10, S791)

• Critical Issues (0)
• Major Issues (0)
• Minor Issues (9)
• Continuous Improvement (3)

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Critical Issues

• None

Major Issues

• None

Minor Issues

• Observatory Shutdown at the end of session generated a 'Scope Failed to Park Correctly' Alert. Newly introduced alert system produced an alert suggesting that the telescope may have failed to park correctly. This was flagged on the Session Webpage as a red alert (which worked well), and reported in the Report File. Checking the data output showed that the Slew to Pre-Park Position and the Park operation had actually both succeeded.   The issue is that the SlewScopeToAzAlt had generated a 'false-alarm' due to the way that scope slew has to be monitored to separate it out from the combined Scope+Dome Slew.  Wait loop added following objScope.Park to ensure scope has achieved 'AtPark' status (with timeout after 2 minutes).
  Fixed 2020-06-12 (AstroMain 3.25.3)
   
• Slew Path and Slew Time for the Telescope Slew to its Pre-Park position was calculated incorrectly. Scope position prior to slew to was Az 128.3° / Alt 79.0° and scope was due to slew to pre-park position at Az 180°, Alt 5° , however slew path building seemingly finished at Az 128.27° / Alt 79.02° (effectively no movement) or at least after < 2.4° movement and produced a scope slew time of 3.8s and slew speed at a remarkable 23.8°/sec, rather than the actual slew time of 33.7s (a speed of 2.7°/sec).  Problems appears to be due to telescope positions only being updated in Device Hub every 2s or so rather than every 0.4s or so in POTH and this confuses the 'SlewTheSkyScopeToAzAlt() routine into thinking that the telescope slew has finished when it hasn't.   Because the routine adds the final Az/Alt position to the SlewPath array, the Slew Path is always completed, but there may be a straight line extrapolation between the final two points.   Fix attempted.
    Done 2020-06-14  (AstroMain 3.25.3)
   
• Slew Paths are based on Az/Alt positions which are only updated every 2 to 2.5s or so in Device Hub. This compares with updates every 0.4s or so in POTH. This generates a slew path with lower resolution (though not sure if path produced from POTH is particularly accurate - it seems rather jagged)   An answer to a query sent to the Help@ASCOMTalks.groups.io forum indicates that when slewing the DeviceHub Az/Alt coordinates are only updated every 1.5s.   AstroMain's Scope code modified to interrogate DeviceHub every 0.2s instead of every 0.4s in order to pick up changes as soon as reasonable and only output changes more than 0.1 arc min movement is detected.
    Done 2020-06-14  (AstroMain 3.25.3)
   
• Dew Heaters value unexpectedly jumped to 98% in middle of day (2020-06-11)  when Tube Temperature was well above both Outside and Env Dew Points and should have seen dew heaters at 0%. Logs show that dew heaters continuously jumped back and forth between 0% and 98% power level for a ~ 70 minute period (11:53:47 to 13:04:54) and giving an average value of around 45-50%.  Monitor file hints that the jump to 98% may be related to weather Data going offline several times during this period. (null outside temperature, null dew point temperature ?).
    Fixed 2020-06-25  (AstroMain 3.25.4)
   
• Automated Dew Heater control stopped working at 08:08:41 (2020-06-12), heaters left stuck on 50% throughout day.  Log file shows 'Exception whilst trying to set Dew Heaters'  'CommandString' ?  Setting dew heaters was unsuccessful.  Resolved later in the day by stopping and restarting services. Problem is definitively related to a UPB lost connection event that results in the following ASCOM dialog window.  
  
  Three problems here:  
    1) ASCOM Switch loosing conection with powerbox - May or may not be able to do anything about this
    2) AstroMain not recognising the failure in Switch and not taking action to restart it - Fixed, AstroMain 3.25.4
    3) Stuck values being sent to ObsEnv record rather than null values.  - Fixed, AstroMain 3.25.3
    Fixed 2020-06-25  (AstroMain 3.25.4)
   
• Multiple ASCOM Powerbox Switch Dialog Messages (2020-06-26). Although a workaround has been implemented in AstroMain 3.25.4 to automatically restart the ASCOM.UPB Switch driver when it unexpectedly disconnects in order to keep automated dew control and dew heater graphs working without significant interruption, the dialog windows associated with each disconnection event are left open until manually closed by the user.  7 disconnection events recorded over an 18 hour period  :  2020-06-26  20:35,   2020-06-27  09:45, 14:35, 18:51,  2020-06-28  06:46, 08:25, 09:3.   Problem appears to have become more frequent since using new Auomated dew control method that uses feedback loop to set dew heaters to maintain tube temperatures at certain temperatures above outside dew point & abiove obs.env. (UPB) dew point. It is conjectured that the problem is somehow related to a conflict in the driver between Switch reads (requested by one AstroMain thread) and Switch writes (requested by another AstroMain thread.   An initial attempt to eliminate the disconnection events by using a 'lock' variable to coordinate read and write requests by AstroMain (3.25.4) didn't improve the situation.  A new attempt to fix the issue (3.25.5) using two UPB_Switch objects was tried but didn't resolve the issue and created a new issue, so reverted back to using just one UPB Switch object (3.25.6). Problem has been reported to Pegasus Astro.   Problem seemed to resolve itself after restarting the UPB software (UPB software had been running for some 4 weeks and its memory usage had reached 3,100,000 KB !)
    Resolved 2020-07-03  (AstroMain)
   
• ObsEnv graphs showing regular data gaps on 8 hour plots (2020-06-26).  Investigating showed that ObsEnv records are only getting written every 2.7 mins rather than every 30s.  Problem was caused by an implicit assumption in AstroWeather code that the computer time of AllSky Computer was the same or very close to that on the Observatory Computer due to Dimension4 synchronising time against an international time server every 30mins. However the time server used by  AllSky Computer had gone offline a few days ago, leading to the a time drift of 150s between the two computers and exposing the weakness in the code.    AstroWeather code fixed to allow for a potential time difference between the two computers (could there be other similar issues in AstroMain, AstoAllSky, AstroWeather ?)
    Fixed 2020-06-28 (AstroWeather 1.10.8)
   
• Certain Wind Direction indicators on Wind Speed graphs are being formed from overposted arrows. Wind Direction indicators (2020-06-26) New wind direction indicators have been recently added to wind speed graphs.    Following an outage of the AllSky Computer on 2020-060-26 when no wind data was collected, the first wind direction indicator after this outage was formed from multiple arrows.   The first window direction indicator will also sometimes show the same problem. 
    Fixed 2020-06-28 (AstroWeather 1.10.8)
   
• Rain Radar Maps stopped displaying (2020-06-28) . Dark Sky Rain Radar maps embedded on Current Weather web page stopped working. This is very probably related to the ending of DarkSky website maps and embeds on 1st July 2020 which is brought about following the takeover of Dark Sky by Apple.     Problem resolved by embeddingRain Viewer radar maps (rainviewer.com)
    Fixed 2020-06-28 (Website)

Continuous Improvement

• Read value of TELEAPI's 'ASCOM Driver ID' at Session Startup check that it is as expected
  This is found in registry at Computer\HKEY_CURRENT_USER\Software\Classes\VirtualStore\MACHINE\SOFTWARE\WOW6432Node\SPACE.com\TheSky TeleAPI-ASCOM Plugin
    Done 2020-06-14  (AstroMain 3.25.3)
   
• Modify 'Temperature Difference from Dew Point' Graphs to show 'EnvDewPointDIfference' instead of EnvTempDifference.
  TGraph ID 37 & 38 to be modified to Show 'Outside Dew Point' instead of 'Outside Temperature Difference' and show EnvDew Point Difference' instead of ' EnvTempDifference'
    Done  2020-06-16 (AstroWeather 1.10.6)
   
• Add Wind Direction indicators to Wind Speed Graphs. Add Wind Direction indicators to Wind Speed Plots, with plot frequency appropriate to the Plot Duration. Say every 3h for 5 day plots (GraphID 9),    every 1h for 16 hour plot (GraphID 49),  every 20 or 30 min for 8 hour plot (GraphID 4)
  See graph of newly inroduced wind direction annotation.
    Done  2020-06-20 (AstroWeather 1.10.7)

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2020-06-22

Wind Data Outage

A relatively frequent (once per fortnight) problem with my weather station (WMR80 Oregon Scientific Weather Station) is that wind speed and direction data stops being accessible to the Base Station and is consequently not available to the Virtual Weathetr Station program running on the AllSky/Weather Computer and thus not available for automated wind speed monitoring for the observatory or for wind data graphing (8 hour plot, 16 hour plot,  5 day plot).

During the second part of 2020-06-21 the wind data became somewhat irregular with pauses in data for up to 15 mins. During the following morning 2020-06-22 the wind data frooze totally.  None of the previous methods to 'restart' wind data supply worked  (ie adjusting the base station position, resetting the base station, resetting the wind sensor, restarting VWS etc didn't work). Batteries in base station and wind sensor were both checked and found ok.

After trying lots of things I resigned myself to the likelihood that the relatively new wind sensor (installed 2019-09-09) had somehow developed a fatal fault.   Happily however and not without some bafflement the wind data came back on line all by itself after being off line for some 14 hours.

The wind data outages on 2020-06-21 & 2020-06-22 are shown on the following 5 day wind speed chart.
(The chart also shows the newly introduced wind direction annotation)

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