David's Astronomy Pages Notes - Session 789 (2020-06-01)

Notes (S788)

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Notes (S790)

	Session Aims & Highlights
	- Observing Result  - Night Summary Plot  - Session Event Log
	Operational Issues
	- Critical Issues (0),  Major Issues (0),  Minor Issues (3),  Continuous Improvement (10)
	Images from 2020-06-01 >>
	2020-06-04
	Investigation: Opening Dome Issue (S755 & S763)
	2020-06-05 to 2020-06-08
	ASCOM.DeviceHub
	Dew Heater Control

Session Aims & Highlights (2020-06-01)

Main aims

1. C/2020 F8 (SWAN): Image this comet using multiple 10s exposures in an attempt to overcome the bright NE sky associated with the developing dawn.
2. NGC 6309. Image Ast. Now Deep Sky Challenge Object (Jun 2020)
3. Targets: Acquire images of a number of targets if conditions allowed.  

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
• SharpCap 3.2, PHD2  2.6.8
   
• AstroMain 3.24.4,  AstroGuard 1.3,   AstroPlan 1.15.2,  AstroShCap 1.2.22, AstroVOE 1.3.6, UPB 1.5 
  (AstroWeather 1.10.1, AstroAllSky 3.6)
  

Highlights

•  Targets.  NGC 6309 successfuly imaged.

Lowlights

• C/2020 F8 (SWAN).  Failed to acquire images (target not included in Plan, although set as a Must-Include target).

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 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 00:21:27 Session Created Live Session Created (2020-06-01 S00789, ImageSaveNum: 789001) 00:21:30   Services Started Observatory Services started 00:21:40   Scope Switched On Telescope Power has been switched on via UPB Powerbox. 00:23:29   Services Started Observatory Services started 00:24:02   Camera1 Connected SBIG Camera Connected (set point -10°C) 00:24:19 Observatory (Auto) Observatory placed in Fully-Automated Mode 00:24:21 Session Pending Session pending (2020-06-01) 00:24:23 Session Initiating Session initiating (2020-06-01) 00:24:25   Plan Requested Observing Plan requested from AstroPlan (1.15.2) 00:24:49   Plan Loaded Observing Plan loaded to queue (2020-06-01 V1 BEST PLAN, Plan ID: 518) 00:24:53   Camera1 Connected SBIG Camera Connected (set point -10°C) 00:24:58   Telescope Connected Telescope Connected (TheSky6) 00:25:10 Session Equilibration Session ready for dome & camera equilibration 00:25:55   Shutter Opened Shutter opened (opening time 45s) 00:25:58   Equilibration Started Dome Equilibration started 00:26:00   Equilibration Skipped Dome Equilibration skipped by user 00:26:02 Session Running Session running 00:26:04   Queue Started Observing Queue started (7 targets selected) 00:26:56       Focusing Started-Foc1 Foc1 Focusing Started (TCF-S) 00:29:45       Focusing Completed Foc1 AutoFocus Completed (Profile No 1) 00:30:19     Target Started (1/7) Target started (1/7, NGC 4651) 00:35:30       Focusing Started-Foc1 Foc1 Focusing Started (TCF-S) 00:38:22       Focusing Completed Foc1 AutoFocus Completed (Profile No 2) 00:51:07     Target Completed Target completed (1/7, NGC 4651) 00:51:09     Target Started (2/7) Target started (2/7, GCVS SS Her) 00:53:48       Focusing Started-Foc1 Foc1 Focusing Started (TCF-S) 00:56:50       Focusing Completed Foc1 AutoFocus Completed (Profile No 3) 01:00:07     Target Completed Target completed (2/7, GCVS SS Her) 01:00:09     Target Started (3/7) Target started (3/7, NGC 6309) 01:03:11       Focusing Started-Foc1 Foc1 Focusing Started (TCF-S) 01:06:14       Focusing Completed Foc1 AutoFocus Completed (Profile No 4) 01:16:17     Target Completed Target completed (3/7, NGC 6309) 01:16:19     Target Started (4/7) Target started (4/7, HIP 87937) 01:18:57       Focusing Started-Foc1 Foc1 Focusing Started (TCF-S) 01:21:59       Focusing Completed Foc1 AutoFocus Completed (Profile No 5) 01:24:22     Target Completed Target completed (4/7, HIP 87937) 01:24:24     Target Started (5/7) Target started (5/7, GCVS CI Cyg) 01:26:11       Focusing Started-Foc1 Foc1 Focusing Started (TCF-S) 01:29:02       Focusing Completed Foc1 AutoFocus Completed (Profile No 6) 01:32:42     Target Completed Target completed (5/7, GCVS CI Cyg) 01:32:44     Target Started (6/7) Target started (6/7, GCVS SS Cyg) 01:35:14       Focusing Started-Foc1 Foc1 Focusing Started (TCF-S) 01:37:58       Focusing Completed Foc1 AutoFocus Completed (Profile No 7) 01:41:38     Target Completed Target completed (6/7, GCVS SS Cyg) 01:44:34   SoftSuspend Called Soft Suspend is called due to Deteriorating Conditions (reducing clarity) 01:45:04   SoftSuspend Cancelled Soft Suspend is cancelled due to Improved Conditions 01:46:34   SoftSuspend Called Soft Suspend is called due to Deteriorating Conditions (reducing clarity) 01:46:39   SoftSuspend Cancelled Soft Suspend is cancelled due to Improved Conditions 01:46:56     Target Started (7/7) Target started (7/7, NGC 582) 01:47:24   SoftSuspend Called Soft Suspend is called due to Deteriorating Conditions (reducing clarity) 01:50:17     Target Failed Target failed due to cloud (7/7, NGC 582) 01:50:19   Queue Paused Queue paused for SoftSuspend 01:50:22 Session Suspended Session suspended 01:50:24   Queue Completed Job Queue completed 01:50:26 Session Closing Session closing 01:51:05   Shutter Closed Shutter closed (closing time 45s) 01:51:26   Dome Parked Dome parked (parking time 22s) 01:52:37   Telescope Parked Telescope parked (parking time 64s) 01:53:07   Scope Switched Off Telescope Power has been switched off via UPB Powerbox. 01:53:51   Services Stopped Night Services stopped 01:53:53 Session Housekeeping Housekeeping Started (Cleanup FITS, Create Fits Summary, Transfer Files) 01:53:59 Session Finished Session Finished

Session Alerts

Time     Alert Detail -- No Alerts                --

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Operational Issues (2020-06-01, S789)

• Critical Issues (0)
• Major Issues (0)
• Minor Issues (3)
• Continuous Improvement (10)

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Critical Issues

• None

Major Issues

• None

Minor Issues

• Actual Start is not being displayed in Report file. Field is showing as either 'blank' or text corresponding to Comment . Actual Start for Target 3/7 (NGC 6307) was been displayed as 'Deep Sky Challenge, Jun 2020'. Problem caused by reporting 'S2' before S2 has been reset to ' StartTime (local)'
  Fixed 2020-06-02 (AstroMain 3.24.5)
   
• Pressure Chart is showing a data gap at same time that Observatory Temperature & Humidity are blank / null.  Time Period 2020-06-07 04:15 to 05:50.    Wind data and outside temperature & humidity have valid values so it shouldn't be general Weather Station / Communication Issue.   dbase.csv file shows valid pressure data over the gap, with pressure changes at 03:26, 04:25, 05:39, 06:40.   Obs. Temp/Obs.Humidity show valid data over the gap. although Obs.Humidity is stationary on 85%, Obs. Temp changes at 03:11, 03:42, 04:16, 05:54, 06:28 .   It seems that Obs.Temp/Humidity are being blanked out 04:16 to 05:54 as their data is stationary for 98 minutes.  Pressure data was blanked due to a bug (sideeffect of Obs Temp/Humidity blanking). Pressure data only stationary for 74 minutes (and the stationary period 04:25 to 05:39 doesn't fit with the gap observed).
  Fixed 2020-06-07 (AstroWeather 1.10.4)
   
• Connect Hub Services doesn't start Telescope service (it starts Dome Service twice !).  Bug is now fixed. Poth Services has also been renamed now as Hub services in the code in view that Device Hub will be eventually replacing POTH.
  Fixed 2020-06-08 (AstroMain 3.25.1)

Continuous Improvement

• Change overall 'Guiding Results' to 'Guiding Results Total'  in Report file
  Done 2020-06-02 (AstroMain 3.24.5)
   
• Reduce white space between Guiding and Focusing sections. Also remove one Tab2 from 'QC Best Focus'
  Done 2020-06-02 (AstroMain 3.24.5)
   
• Modify format on Session Notes page to increase clarity and remove duplicate session links
  Done 2020-06-07 (Web Site)
   
• Calculate and draw moving average Dew Heater value on Dew Heater Graphs (GraphID 17 & 50)
  Done 2020-06-04 (AstroWeather 1.10.2)
   
• Modify 'Close Shutter' subtitle to 'Close Dome' .
  Done 2020-06-04 (AstroWeather 1.10.2)
   
• Change flag for SessionEvent 'Program closed by User' from Green (1) to Yellow (2)
  Done 2020-06-04  (AstroMain 3.25.1)
   
• Change name of SessionEvent 'Scope Switched Off' to 'Telescope Switched Off'
  Done 2020-06-04  (AstroMain 3.25.1)
   
• Create and use a 'DewHeaters' object.  Create a new independent object for 'DewHeaters'. Dew Heater code currently sits in standalone routines within PowerBox.vb module.
  Done 2020-06-07  (AstroMain 3.25.1)
   
• Create and use a 'PowerBox' object.  Create a new independent object for UPB (Powerbox Switch, Env Sensors and Focuser2) . PowerBox code currently sits in standalone routines within PowerBox.vb module.   TPowerBox class and PowerBox object added to AstroMain.  Module name 'PowerBox' had to be renamed as 'Powerbox_UPB' in order to expose the new PowerBox object.
  Done 2020-06-10  (AstroMain 3.25.2)
   
• Modify 8hr Dew Point and DPP Graphs to being 16hr plots. Graphs 11 to be made 16h plot. Graph 38 to be made a 16h plot  its Graph Height to be increased by 100px, its Y Axis max value to be increased to 10 and Y Major to be changed to 1. Also check why there is an anomalous short vertical purple line from 0 to -1 DPP  (old debugging code or a minor data anomaly ?). Plot Positions to be moved on Current Weather Web Page. Also Graph 37 height to be increased by 50px and its Y Axis max value to be increased to 10 and its Y Major to be changed to 1.
  Done 2020-06-08  (AstroWeather 1.10.5 & WebSite)

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2020-06-04

Investigation: Opening Dome Issue (S755 & S763)

Issue : Initial problems opening Dome Shutter (Sessions S755 & S763)
When using AstroMain's manual 'Open Shutter' button the shutter would seem to begin opening on ObsViewer but then immediately shut.  No obvious messages or errors given. Weather conditions fine. This happened twice in a row. On third attempt and (after clicking Open Shutter in POTH) the Shutter opened ok.  Issue has been seen previously (e.g. Session S755)

Problem was investigated by looking through data from session S763.  

AstroMain Report Logs (S763)

Logs show Open Dome routine being called twice at 19:38 but dome shutter didn't appear to Open. A third call to Open Dome at 19:40 successfully worked.

AstroMain ObsPics  (S763)
Obs Pics show the Dome rotating from Az 090 (Park Position) to ~Az 180 (Scope Position) at around 19:38 to 19:39. This was in response to turning on Dome Slaving
The Pics don't capture situation where dome appears to begin opening. This is probably because pics are only saved at intervals of  30s or so, and will be unlikely to capture events that the display (updated every 2s) might show.

AstroGuard (S763)
AstroGuard doesn't show anything until Services where run at around 20:05 at which point the Dome was already found to be open.

Ascom Trace Logs (S763)
ASCOM Trace Log for Dome shows

19:38:18 Volatitle               90.0 ....    (Dome at Az 90)
19:38:19 SlewToAzimuth  180.2
19:38:19 Slewing Get         False     (is slewing)
19:38:21 OpenShutter
19:38:23 ShutterStatus 1  (closed)
19:38:45 OpenShutter      
19:38:45 ShutterStatus 2  (presumed opening)
19:38:46 ShutterStatus 1  (closed)
19:39:00 Volatitle               180.2    (Dome at Az 180.2)
19:39:00 Slewing Get        True      (is not slewing)
19:39:16 OpenShutter
19:39:17 ShutterStatus 2 (presumed opening)
19:39:17.ShutterStatus 1 (closed)
19:40:10 OpenShutter
19:40:10 ShutterStatus 2  (presumed opening)
19:40:12 ShutterStatus 2  (opening)
19:40:53 ShutterStatus 0  (open)

Note
When Dome is Slewing  Trace Log shows           'Slewing Get         False'
When Dome is Not Slewing    Trace Log shows  'Slewing Get         True'

This seems opposite to that expected.   Prehaps 'False' means dome can't slew (it is already slewing) and 'True' means dome can be slewed.

Conclusion
Commands to Open Shutter won't operate if the dome is in process of slewing (slewing has to be finished in order for Open Shutter commands to work)

It is likely that Close Shutter commands also won't operate whilst the dome is in process of slewing.

Recommendation
User should take note of the slewing status of the dome before using an Open Dome operation.

Code for Open Dome should check if Dome Slewing is in progress and warn user (manual mode) or wait to Dome Slewing is completed (automated mode)

For rapid closure of Dome in the event of rain etc, it would probably be appropriate to check Slewing Status of the Dome and send an Abort Command to Dome (to stop any slewing in progress) so that Close Shutter can immediately operate in the event of critical weather conditions / Hard Suspend due to rain etc.

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2020-06-05 to 2020-06-08

ASCOM.DeviceHub

DeviceHub
Device Hub provides the ability to use the ASCOM Platform and conforming drivers to control a telescope, a dome, and a focuser. This is similar to the venerable POTH Hub tool. It is intended that DeviceHub replaces POTH before Microsoft drops support for the Visual Basic 6 runtime libraries.

The Device Hub also provides itself as a local server for a telescope, a dome, and a focuser. Just like POTH, Device Hub can also provide dome slaving transparently from the viewpoint of a connected telescope client.

Installation
As part of preparation for moving over to using DeviceHub, the latest version of DeviceHub (6.4.1.7) was downloaded today (2020-06-04) from github  https://github.com/ASCOMInitiative/ASCOMDeviceHub  and installed on the development computer (running ASCOM Platform 6.4 SP1, build 6.4.1.2695). A copy of DeviceHub manual was also downloaded.

DeviceHub was started to confirm that installation was successful and the application was basically operating  ok (but without connecting to a simulator dome and a simulator scope in the first instance)

Data Fields
ASCOM Profile Explorer was used to look up data fields for ASCOM.DeviceHub.Dome and ASCOM.DeviceHub.Telescope to understand any key difference s with Datafield used by POTH.Dome and POTH.Telescope

Main differences :

DeviceHub.Dome  uses 'Dome ID'   whilst POTH.Dome uses 'DomeID'
DeviceHub.Dome doesn't have the equivalent of POTH.Dome  'DomeName'

DeviceHub.Telescope  uses 'Telescope ID'   whilst POTH.Dome uses 'ScopeID'
DeviceHub.Telescope doesn't have the equivalent of POTH.Telescope  'ScopeName'

Integration with AstroSuite / Clair Observatory

Plan for integrating DeviceHub into Clair Observatory Software Suite (AstroMain, AstroGuard, TheSky6, PHD2) is shown plan along with current status:

Development Computer
Install DeviceHub on Development Computer
Understand differences between DeviceHub and POTH
Edit Dome Settings with Dome Parameters associated with Clair Observatory
Confirm basic operations of DeviceHub with connection to Simulator.Dome and Simulator.Telescope

AstroMain &TheSky6
Modify AstroMain to work with DeviceHub
  - Add UseDeviceHub checkbox (checked = Use DeviceHub, unchecked = Use POTH)
  - Modify Dome.Connect routine to be able to connect to DeviceHub.Dome
  - Add new function GetDomeSubID (to get DomeID of dome attached to DeviceHub.Dome or POTH.Dome
  - Add new function SetDomeDevice to replace older function
  - Modify Scope.Connect routine to be able to connect to DeviceHub.Dome
  - Add new function GetScopeSubID (to get TelescopeID of telescope attached to DeviceHub.Telescope or POTH.Telescope)
  - Add new function SetScopeDevice to replace older function
  - Modify Dome.Disconnect and Scope.Disconnect routines
  - Modify Setup Hub to use DeviceHub

Build & Test new AstroMain version (3.25.2 )
  - Confirm connection to DeviceHub.Dome and DeviceHub.Telescope from AstroMain (working with Simulators)
  - Manually edit TeleAPI.Scope in TheSky6 to link to DeviceHub.Telescope
  - Confirm connection to DeviceHub.Telescope from TheSky6 (manually edit of TeleAPI.Scope to link to DeviceHub.Telescope)
  - Confirm read-access to Dome Az. ShutterStatus, Scope Ra/Dec, Scope Az/Alt, ScopeStatus etc
  - Confirm function SetTracking, SetSlaving,  Open/Close Shutter, ParkScope, ParkDome etc
  - Confirm continued Dome/Scope functionality using POTH

AstroGuard
Modify AstroGuard to work with DeviceHub
  - Add UseDeviceHub checkbox (checked = Use DeviceHub, unchecked = Use POTH)
  - Modify ConnectDome to be able to connect to DeviceHub.Dome
  - Add new function GetDomeSubID (to get DomeID of dome attached to DeviceHub.Dome or POTH.Dome
  - Modify ConnectDome to be able to connect to DeviceHub.Dome
  - Add new function GetScopeSubID (to get TelescopeID of telescope attached to DeviceHub.Telescope or POTH.Telescope)

Build & Test new AstroGuard  version (1.4)
  - Confirm connection to DeviceHub.Dome and DeviceHub.Telescope from AstroGuard (working with Simulators)
  - Confirm read-access to Dome Az. ShutterStatus, Scope Ra/Dec, Scope Az/Alt, ScopeStatus etc
  - Confirm function Close Shutter,  ParkDome, ParkScope
  - Confirm continued Dome/Scope functionality using POTH

PHD2
  - Manually edit Mount setting to link to DeviceHub.Telescope
  - Confirm connection to DeviceHub.Telescope from PHD2

AstroLaunch
Extend 'Kill Stranded' Processes' to include ASCOM.DeviceHub
Build & Test new AstroLaunch version (1.4)

AstroProtect
Modify AstroProtect to able to connect to scope via DeviceHub
Build & test new AstroProtect version (1.4)

Observatory Computer
Install DeviceHub 6.4.1.7 on Observatory Computer  (2020-06-07)
Edit Dome Settings with Dome Parameters associated with Clair Observatory
Confirm basic operations of DeviceHub with connection to Simulator.Dome and Simulator.Telescope
 Waiting on new version of DeviceHub that resolves connection issue with MeadeLX200GPS.Telescope (2020-06-07)
Install DeviceHub 6.4.1.8 on Observatory Computer (2020-06-08 am)
 Waiting again on new version of DeviceHub that resolves connection issue with MeadeLX200GPS.Telescope (2020-06-08)
Install DeviceHub 6.4.1.10 on Observatory Computer (2020-06-08 pm)

AstroMain &TheSky6
Install new version (AstroMain 3.25.1)
  - Confirm connection to DeviceHub.Dome and DeviceHub.Telescope from AstroMain (working with Simulators)
  - Confirm 'Setup Hub works'
          (i.e. sets DeviceHub to use ASCOM.Pulsar_Observatories_Dome.Dome and MeadeLX200GPS.Telescope)
  - Confirm connection to ASCOM.Pulsar_Observatories_Dome.Dome from DeviceHub
  - Confirm connection to MeadeLX200GPS.Telescope from DeviceHub 6.4.1.7 (FAIL - See below)
  - Confirm connection to MeadeLX200GPS.Telescope from DeviceHub 6.4.1.8 (FAIL)
  - Confirm connection to MeadeLX200GPS.Telescope from DeviceHub 6.4.1.10 (SUCCESS, 2020-06-08)
  - Manually edit TeleAPI.Scope in TheSky6 to link to DeviceHub.Telescope
  - Confirm connection to DeviceHub.Telescope (MeadeLX200GPS.Telescope) from TheSky6
  - Confirm read-access to Dome Az. ShutterStatus, Scope Ra/Dec, Scope Az/Alt, ScopeStatus etc
  - Confirm function SetTracking, SetSlaving,  Open/Close Shutter, ParkScope, ParkDome etc
  - Confirm continued Dome/Scope functionality using POTH
  - Perform Live Session Test (DONE S790, 2020-06-08)
Install new version (AstroMain 3.25.2)  with DeviceHub set as default Hub

AstroGuard
Install new version (AstroGuard 1.4)
  - Confirm connection to DeviceHub.Dome and DeviceHub.Telescope from AstroGuard (working with Simulators)
  - Confirm read-access to Dome Az. ShutterStatus, Scope Ra/Dec, Scope Az/Alt, ScopeStatus etc
  - Confirm function Close Shutter,  ParkDome, MoveScope
  - Confirm continued Dome/Scope functionality using POTH

PHD2
  Manually edit Mount setting to link to DeviceHub.Telescope
  - Confirm connection to DeviceHub.Telescope from PHD2
  - Confirm guiding operations work from PHD2

PemProV2
  Manually edit Mount/Scope ASCOM driver to link to DeviceHub.Telescope
  - Confirm connection to DeviceHub.Telescope from PemProV2

AstroLaunch
Instal new version (AstroLaunch 1.4)
Instal new version (AstroLaunch 1.4.1) with DeviceHub set as default Hub

AstroProtect
Install new AstroProtect version (1.4.1)

Key
	Completed	In Progress	Issue	To Do

Issues seen

• AstroMain connected to Pulsar Dome (with no connection to any telescope) via POTH Hub, crashed shortly after DeviceHub was connected to Simulator.Dome and Simulator.Telescope.  Debugging showed the following exception.
  System.ArgumentException  HResult=0x80070057
Message=Argument 'Length' must be greater or equal to zero. Source=Microsoft.VisualBasic.  StackTrace:
at Microsoft.VisualBasic.Strings.Right(String str, Int32 Length)
at CCDApp2.PulsarDomeMonitor.GetLatestPulsarLogFile() in C:\Users\David\Documents\Visual Studio 2017\Projects\AstroMain\Dome.vb:line 1245
at CCDApp2.PulsarDomeMonitor.RunPulsarDomeMonitor() in C:\Users\David\Documents\Visual Studio 2017\Projects\AstroMain\Dome.vb:line 1383
at System.Threading.ExecutionContext.RunInternal(ExecutionContext executionContext, ContextCallback callback, Object state, Boolean preserveSyncCtx)
at System.Threading.ExecutionContext.Run(ExecutionContext executionContext, ContextCallback callback, Object state, Boolean preserveSyncCtx)
at System.Threading.ExecutionContext.Run(ExecutionContext executionContext, ContextCallback callback, Object state)
at System.Threading.ThreadHelper.ThreadStart()
  It would seem that Pulsar Dome was still using a log trace file 'ASCOM.Pulsar_Observatories_Dome.1319.570310.txt)  in ..\Documents\ASCOM\Logs 2020-06-04,  and AstroMain wasn't expecting to suddenly find a more ..\Documents\ASCOM\Logs 2020-06-06 folder to have suddenly be opened without a valid Pulsar Trace Log File.  Instead there was a trace file (ASCOM.DomeSim.1627.333010.txt) associated with Dome Simulator that had just been opened by DeviceHub/Dome Simulator.  Additional exception trapping needs to be added to AstroMain to make it more robust to this situation.
  Resolved     (AstroMain )
   
• Unable to connect to Meade LX200 GPS/R telescope from DeviceHub (Device Hub 4.6.1.7 & 4.6.1.8. TraceLog shows unhandled exception :
  System.Reflection.TargetInvocationException: Exception has been thrown by the target of an invocation. ---> System.Runtime.InteropServices.COMException: Member not found. (Exception from HRESULT: 0x80020003 (DISP_E_MEMBERNOTFOUND))
--- End of inner exception stack trace ---
at System.RuntimeType.InvokeDispMethod(String name, BindingFlags invokeAttr, Object target, Object[] args, Boolean[] byrefModifiers, Int32 culture, String[] namedParameters)
at System.RuntimeType.InvokeMember(String name, BindingFlags bindingFlags, Binder binder, Object target, Object[] providedArgs, ParameterModifier[] modifiers, CultureInfo culture, String[] namedParams)
at ASCOM.DriverAccess.TrackingRates.GetEnumerator() in C:\ASCOM Build\Export\ASCOM.DriverAccess\Telescope.cs:line 1551
at ASCOM.DeviceHub.DeviceManagerBase.GetServiceProperty[T](Func`1 getCmd, T defaultValue, ActivityMessageTypes messageType, String propName) in D:\My Projects\Visual Studio 2019\ASCOMDeviceHub\DeviceHub\DeviceManagers\DeviceManagerBase.cs:line 90
at ASCOM.DeviceHub.TelescopeManager.get_TrackingRates() in D:\My Projects\Visual Studio 2019\ASCOMDeviceHub\DeviceHub\DeviceManagers\TelescopeManagerAccess.cs:line 722
at ASCOM.DeviceHub.TelescopeParameters..ctor(TelescopeManager mgr) in D:\My Projects\Visual Studio 2019\ASCOMDeviceHub\DeviceHub\Business Object Classes\Telescope Classes\TelescopeParameters.cs:line 37
at ASCOM.DeviceHub.TelescopeManager.ReadInitialTelescopeDataTask() in D:\My Projects\Visual Studio 2019\ASCOMDeviceHub\DeviceHub\DeviceManagers\TelescopeManager.cs:line 768
at ASCOM.DeviceHub.TelescopeManager.<Connect>b__244_0() in D:\My Projects\Visual Studio 2019\ASCOMDeviceHub\DeviceHub\DeviceManagers\TelescopeManager.cs:line 201
at System.Threading.Tasks.Task.InnerInvoke()
at System.Threading.Tasks.Task.Execute()
  (see more details below). A request for help has been sent to the ASCOM Talk Forum. (2020-06-06 to 2020-06-08) to which Rick B responded and fixed the issue with new version (4.6.1.10) which was successfully resolved the problem during daylight tests  (2020-06-08) and subsequent nighttime live session (S00780, 2020-06-08)
  Fixed 2020-06-08 (ASCOM DeviceHub 4.6.1.10)

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Dew Heater Control

My first dew heater controller had two manual knobs for controlling the power/heating level applied to the two circuits. It was a bit or miss if one selected the right level of heating to control dew without causing too much air currents in the telescope tube that can effect image quality.

Part of the reason for acquiring a Pegasus Ultimate Powerbox (UPB) in Autumn 2018 was a move towards increased Observatory Automation / increased remote control with software/remote access to dew heater controls, allowing the dew heaters to be turned on/off and to be set to specific power levels or run in Auto Mode where the UPB would automatically set the Dew Heater Power based on Humidity.  The algorithum use a simple linear relationship between dew heater power and humidty (thus  60% power at 60% humidity, 95% power at 95% humidity  etc)

A couple  of issues limited the proper operation of dew heaters using UPB until Spring 2019.:

- a voltage supply issue that meant that dew heaters couldn't be turned up to more than 50% level without voltage to UPB dropping too low.
 ( this was due to voltage losses in the 12V extensio cable that was necessarily required between the Pegaus Power Adapter in the Observatory Control Bay and the UPB attached to one of the telescope's fork arms., the issue also prevented runnning dew heaters in Auto Mode,  all control had to be performed 'manually' via the UPB Window). This was eventually fixed by using a special heavy duty 16AWG 12V power lead extension that was purchased from the US in Mar 2019

- an early failure in the Temperature/Humidity Sensor that is attached to the UPB, meant that the UPB didn't have reliable humidity values to run the dew heaters in Auto Mode until a replacement sensor was sent out by Pegasus Astro in Dec 2018

However the originally planned operation of the dew heaters from the AstroMain observatory control program was delayed ountil a fully functioning ASCOM Switch Driver for the UPB eventually became available a year later in Oct/Nov 2019 .

A modifed algorithum for operating the dew heater was incorporated into AstroMain, where Power Level was set to Humidity Value when the Observatory was open, but run at around 60% level when observatory operations where suspended / dome closed, and run at 25-30% when an observatory session wasn't running.

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