David's Astronomy Pages Notes - Session 624  (2018-09-01)

Notes (S623)

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Notes (S625)

	Session Aims & Highlights
	- Observing Result  - Night Summary Plot
	Operational Issues
	- Critical Issues (0),  Major Issues (1),  Minor Issues (2),  Small Defects (0),  Continuous Improvement (0)
	Fully Automated Operation
	Autofocussing
	Images from 2018-09-01  >>

2018-09-01 (Automated Operation Testing)

Session Aims & Highlights (2018-09-01)

Main aims

Main of this nighttime session were

1. Targets. Acquire images for a selection of variable stars, nearby stars, star clusters
   (since moon illumination had dropped below 70% it was anticipated that Schedule Builder would include more Deep Sky Targets, e.g. galaxies, than in the last few sessions)  .
2. Software. Test fixes & modifications made to the Observatory Control Program (CCDApp2) since the last session
3. Stability. Continue checking stability of the Observatory system components (POTH.Hub , Telescope + Dome, Observatory Control Software, Computers)
   

Equipment & Software

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

Highlights

• Targets. Images were successfully acquired from 10 targets
    (with Moon at 62% illumination the Schedule included targets with both Loose C3 constraint (maximum FLI of 1.00) and Medium C2 constraint   (maximum FLI of 0.70), this was enough targets to allow the builder to create a plan for the entire night, although the first half of plan wasn't used on this occasion)
• Stability. Observatory operations were reasonably stable until a 'Timed out waiting for received data' problem prevented the slew of scope to targets during the second half of the session.
    (On the upside there have been no instances of the TheSky6 "Error code=213(0xd5)" during the last x sessions)
• Software. There were no problems with the Observatory Control Program CCDApp2 or its Job Queue freezing up during the session
  (A bug was fixed prior to the session to prevent freezing of the Job Queue and the fix appears to have been successful)
• Monitoring Data. Data was written to (monitor).dat file during the whole session (this had failed in the last 2 sessions)

Summary Plots & Logs

Observing Result (2018-09-01, S624) Observatory Unlocked at 01:11, Operations started at 01:15, Fully-Automated Mode from 01:16, Job Queue started at 01:26,  Scope Connection Problems (slew failures) from 03:06 Job Queue ended at 04:25. Session finished at 04:28

(Observation Status :  Green=Completed, Yellow= Partially Completed, Red= Failed)

Night Sky Summary Plot - 2018-09-01 Top axis: Sky Brightness at Zenith (in ADU/s) Lefthand axis: Local Time (hh LT). Righthand axis: Sun Altitude (degs) Note: Wind Speed values are invalid on this night  (Sensor had disconnected and VWS putting out constant value of 13.2 mph)

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Operational Issues (2018-09-01, S624)

• Critical Issues (0)
• Major Issues (1)
• Minor Issues (2)
• Small Defects (0)
• Continuous Improvement (0)
  

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Critical Issues

• None

Major Issues

•  

  TheSky6 connection to telescope stopped following 'Timed out waiting for received data ' error.   After slewing to the second target in the night (Hickson 97)  an ASCOM Utilities dialog box appeared in TheSky6 saying 'Timed out waiting for received data' and it was noted that the position of the telescope in TheSky6's virtual sky was siting some two 2 degrees from the target, whilst real the telescope was correctly pointing at the target (based on images being received from camera and the telescope position being reported in the POTH window).  Concerned about the implications for the next slew the Scope was manually disconnected and then reconnected in the TheSky6 after which the telescope began appearing at the correct position on the virtual sky. Later during the session a 'Timed out waiting for received data' error again occurred whilst taking images of NGC 5322, and whilst automated Operations were running unmonitored.   (See Fig 1 & Fig 2) The following target (GCVS Z And) and indeed all the remaining targets in the session failed as the telescope didn't slew from its position still on NGC 5322. The slew failures were picked up by the Job Queue executor as a discrepancy between the amount of slewed requested and the amount of slew measured, and execution passed to the next target in turn without imaging.  This seems to be the first time that this problem has been encountered, and at least the first time to see it in definite isolation of other problems (i.e. not mixed in with multiple errors when the Observatory System including TheSky6, POTH & LX200 have become totally unstable). Potential workaround: In the event of a detecting a slewing discrepancy it might be worth commanding TheSky6 to disconnect / reconnect to the telescope and then issue a further 'slew to target' command.  It's unsure if the Error Dialog box has to be acknowledged first, if so, it might prevent this workaround from being successful.
  Resolved in due course (TheSky6, UPB Powerbox)

Minor Issues

• Monitor Data getting written to '(monitor).dat' file.  Issue ok during this session but has been problematic in recent sessions
    Resolved (AstroMain)
   
• Wind Speed values invalid for more than 12 hours .  Values not changing on AllSKy Images and Reports.  Annoying solid filled bar appears in Wind Track on NightSummaryPlot6  (underlying cause is that the Wind Sensor had become disconnected from Weather Station somehow and VWS puts out a constant 'last known value ' rather than marking it as null.  Resolved but still an occasional issue.    Need to have suitable backup AA batteries available.
  Resolved (WeatherStation)

Small Defects

• None

Continuous Improvement

• None

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Autofocussing

An autofocussing run was inserted with Job Queue as part of executing the WDS GRB 34 target, which modified the focus position by 189 steps. The new data point (temperature 14.0°C) was later used to update the current Focus vs. Temperature graph and provide a new temperature corrected focus equation whose coefficients will be used for setting focus positions at the next session
    Focus Position = -127.8 * T + 4805, where T is temperature in °C

(It remains to be whether this equation is a good predictor of focus for temperatures at 3°C and below. The slope of line has been  has been getting less steep as more data in collected in the 9 to 14°C range but is this a consequence of  having more data to define for defining a best fit line or a measure of the uncertainty produced by the spread in measured focus at the same temperature )

Focus Profile (2018-09-01)

Close Up of Focus Profile F0 is the position where the focuser was originally positioned (in this case it was the position calculated from the best temperature based focus coefficients determined from recent sessions). It’s not too bad, but it is clearly on the low side of best focus on this night (or at least at this time). F1a is the best focus position determined from the data and my automated curve fitting method. (I use this to provide a corrective focus offset or empirical fix to the temperature modelled focus position. I use this for the rest of the session or until superseded by a new offset) . F1b is the focus position that I assume other methods might choose as the best focus which is essentially where FWHM measurements were the lowest . (This point is slightly offset on the higher side from F1a. Seeing and/or cloud condition was probably just a bit better when the two points either side of F1b were taken but probably doesn’t give an absolute picture of the best focus position.

Focus vs. Temperature Correlation  (2018-09-01)

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