David's Astronomy Pages Notes - Session 622 Attempt  (2018-08-29)

Notes (S621)

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Notes (S622)

	Session Aims & Highlights
	- Observing Result  - Night Summary Plot
	Operational Issues
	- Critical Issues (0),  Major Issues (2),  Minor Issues (2),  Small Defects (3),  Continuous Improvement (0)
	No Images from 2018-09-29 >>

Session Aims & Highlights (2018-08-29)

This was an attempted nighttime session, but failed to deliver any useful images due to cloudy skies.
The intended session number (S622) will be used instead for the next session.

Main aims

1. Control Program. Test code fixes for displaying of Telescope Activity, Telescope Location and Next Target Locations on AllSky Program products (NightSummary Plot and Annotated AllSky Image)
    (telescope position/activity has been missing from around 30% of AllSky frames during recent sessions, similarly cloud cover at Telescope Position and future targets hasn't been getting measured and communicated around 30% of the time).
2. Autoguiding. Test automated autoguiding using PHD2 and 80mm APO Guidescope with specific attention to selection of a fresh guide star when starting a new target .  
   (Correct selection and lock on to fresh guide star for each new target is critical for Automated Observatory operation)
3. Targets. Acquire images for a selection of variable stars, nearby stars, star clusters and deep sky targets.
4. System Stability. Continue checking stability of the Observatory system components (POTH.Hub (Telescope + Dome), Observatory Control Software, Computers), noting in particular any further re-occurrences of the '203 error', and any cases of lock-up/hanging of the observatory control program (CCDApp2).

Equipment & Software

•  12" LX200 and ST-10XME
•  80mm APO and ZWO ASI 178MC
•  CCDApp2, TheSky6, CCDSoft5, PHD2,  POTH Hub,

Highlights

• Control Program. Telescope Position and Next Targets correctly displayed on Annotated AllSky Images & Annotated Night Summary Plot,  and plotted 100% of the time (test confirms that the bug fix (telescope data only plotting 30% of the time) has been successful )
• System Stability. Observatory operations were stable once Telescope and Dome had been correctly connected. There were no instances of "Error code=213(0xd5)"   (Session was too short to test the effect of recent code modifications designed to make the Observatory Control Program CCDApp2 more resistant to locking-up/hanging)
• Autoguiding. Unfortunately, no opportunity to test PHD2' automatic guide star acquisition due to Cloudy Skies
  (PHD2 / Automated Autoguiding tests will be carried through to the next session)
• Targets. Unfortunately, no opportunity to acquire images of planned targets due to Cloudy Skies

Summary Plots & Logs

Night Sky Summary Plot/a> - 2018-08-29 Top axis: Sky Brightness at Zenith (in ADU/s) Lefthand axis: Local Time (hh LT). Righthand axis: Sun Altitude (degs) Shutter Status (open/shut) & Telescope Status (parked, inactive and active use) shown in tracks on right hand side

Annotated AllSky Image, 2018-08-29 21:59:40 (Local) Cloud at the current telescope position (target C/2016 R2 (PanStarrs) ) explains why 4 succesive 'locate images' contained too few stars to link, causing Precision Centering to fail.

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Operational Issues (2018-08-29, S622A)

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

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Critical Issues

• None

Major Issues

• Telescope Pointing to incorrect Az/Alt on TheSky6 virtual sky.  Upon starting POTH.Hub (POTH.Telescope and POTH.Dome) and connecting to the LX200 telescope from TheSky6 , the telescope was found to be pointing to a location close to the eastern horizon, rather than its expected position at/very close to the Park location which is close to southern horizon , but due south.  Az/Alt and RA/Dec both appeared correct on the POTH window. I checked to ensure that TheSky was set to use Computer Clock, which it was.  I had recently had TheSky6 set to use a location in Texas, USA which might cause the problem so I checked to see that TheSky6 had been reset to use by Observatory's Lat/Long , which it was, but just to be sure I reset Lat/long again. The telescope still pointing to the wrong position in TheSky6. Unhappy about beginning the session involving automated slewing to a series of targets without being sure that telescope would slam into its base, it was decided to restart the entire suite of Observatory software (TheSky6, CCDSoft5 and CCDApp2).  Upon restarting and reconnecting the telescope, it was found to now be pointing in TheSky to a location which was consistent with it's actual location, close to its Park Location). Whilst Lat/Long and Computer Time appear to have both been set ok, it would seem that TheSky6 was still using  an inappropriate Time Zone setting (6), left over from my earlier Texas looksee, rather than the correct Time Zone setting (0). This would seem to explain why the telescope appeared at to be 90-105 deg off in azimuth in the TheSky but at correct position in POTH and in Autostar II.  (Fig 1) Issue resolved. Need to make sure Time Zone is correct in TheSky6 before starting a live session by visual inspection (especially if TheSky location had been recently modified to a site other than that of the observatory) or by value inspection using code (if possible) , or by setting required time zone explicitly.
  Resolved in due course (AstroMain, TheSky6
   
• POTH.Dome not correctly connecting to Pulsar Dome.  Upon starting POTH.Hub (POTH.Telescope and POTH.Dome) with Dome already set to "Pulsar Observatories Dome ", the initial commands to Open Shutter and Slave Dome went unheeded.  Checking Dome setup in POTH Setup showed that the COM Port for the Dome was set to COM11 (as it sometimes is) . Clicking on Search changed the port to COM9.  Clicked Ok,  at which  point the shutter immediately began opening and the dome began rotating around to align with the telescope.  The Pulsar Observatories Dome on my system is found to to sit on either COM9 or COM11 even though the USB cable to the Dome Controller is always plugged into same USB cable port on the USB Hub which is plugged into the same USB Port on the computer. Not sure why the COM port jumps around.     A partial workaround is to always do a search for the connected COM Port before initiating automated observatory operations. This has to be be done by 'manually' pressing the right buttons in POTH Setup. If in doubt the USB Com Port would normally be seen in Window's Device Manager. A workaround was eventually employed in AstroMain that would check the port number that dome was on (it was always one of two potential COM Ports) and adjust the COM Port in ASCOM Profile accordingly. The issue with COM Port Switching eventually went away when the Observatory Computer (with Window 7/10) was replaced with a new one (with Windows 11 OS).
  Resolved in due course (AstroMain, Observatory Computer)

Minor Issues

• Telescope Slew failed (Tracking in OFF state). Slew to target (GCVS SS Her) failed. Message from POTH /TheSky6 stating that Telescope Tracking was set to the wrong state. Whilst slews are known to fail if telescope tracking is set to Off, and code had been recently modified to command a Telescope Tracking to ON at a certain point before commanding a slew,  a particular set of events meant that the command turning Tracking On was superseded by a command setting Telescope Tracking to OFF before slew occurred (this being a command performed after around 15 mins of observatory being suspended, to make sure that telescope/camera cables don't get wrapped around the pier. (Fig 2).  Fixed, code modified so that it examines telescope tracking state prior to making a slew and if necessary set it to ON prior to making the slew.
  Fixed (AstroMain TheSky6)
   
• PHD2 Autoguiding Software not selecting a fresh star to use as guide. Observatory Control program uses OpenPHD2 to send commands to PHD2 software and listen for messages in return.   It is used to initiate autoguiding using Guidescope / ZWO ASI178MC camera from within the Job Queue execution after slewing to and centering targets with exposure > 30s.  Guiding results are sent for QC and recording with the image observations. Autoguiding is terminated before slewing to the next target. .
  Fixed (AstroMain, PHD2)

Small Defects

• More than one AllSky Cloud Measurement being reported in short succession when cancelling multiple frames (to prevent target overrunning the allotted time slot).  Current and Next Target showing same Cloud Measurement (coincidence or bug ?)
  Fixed (AstroMain, AstroAllSky)
   
• AllSky Cloud assessment needs improving.
  Done (AstroAllSky)
   
• Query over CCD Camera cooling (power levels seem to steadily increase with time rather than reaching a plateau)
  Close (SBIG Camera, CCDSoft, AstroMain)

Continuous Improvement

• None

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