David's Astronomy Pages Notes - Session 610.1  (2018-05-05, Observatory Commissioning)

Notes (S609)

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Notes (S610.2)

	Session Aims & Highlights
	- Night Summary Plot
	Operational Issues
	- Critical Issues (0),  Major Issues (2),  Minor Issues (0),  Small Defects (5),  Continuous Improvement (0)
	No images from this session  >>

Session Aims & Highlights (2018-05-05)

Main Aims

This was a night-time session to start formal commissioning of the new Dome Observatory including :

1. General. Check observatory for any general issues & problems (night time access, lights, safety, equipment start up etc)
2. Dome Slaving. Operate telescope and dome together using POTH.Hub with dome slaving
3. Telrad. Align telrad with scope, align scope on a known star and synchronise position
4. SBIG Camera. Check focus & camera orientation (180 deg +/-)
5. Telescope Park. Set up telescope Park position. 
6. Observatory Shutdown. Test observatory shutdown including Close Shutter, Park Dome & Park Telescope
7. System Stability. Check stability of the overall system (POTH.Hub and observatory control software)

Equipment & Software

•  12" LX200 and ST-10XME
•  CCDApp2, TheSky6, CCDSoft 5, POTH Hub

Highlights

• General. There were some positive aspects / lesson learned from operating the new Dome Observatory at night and using POTH.Hub with a live telescope and dome,  but there were a number of issues that need to be sorted out during the course of the next few commissioning sessions
  Dome Slaving.  Dome Slaving largely worked but an issue arose when LX200 and/or POTH.Hub began carrying an incorrect LST
• Telrad. was eventually aligned with the scope, and the scope aligned on a known star (Arcturus), Park Position set (Altitude 0, Azimuth 180) and the scope and dome successfully parked at close-down.
• Telescope Park. Telescope Park position was set-up but an issue arose on parking telescope involving TheSky6 timing-out waiting for received data.
• Observatory Shutdown. Close Shutter, Park Dome operations ok but there was an issue with Park Telescope
• General.  There were some critical instability issues that need to be sorted out before the next commissioning session(s)

Notes

Telrad attached to dovetail & 12" LX200GPS Telrad has been screwed to a male dovetail, taken from Meade finder scope that is not used, to provide a more secure attachment than the normal sticky pad attachments.

Summary Plots & Logs
 

Night Sky Summary Plot - 2018-05-16 Top axis: Sky Brightness at Zenith (in ADU/s) Lefthand axis: Local Time (hh LT). Righthand axis: Sun Altitude (degs)

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Operational Issues (2018-05-05, S610.1)

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

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Critical Issues

• None

Major Issues

• CCDApp2 Observatory Control Software issues- Program Crash.  Program crashed whilst performing plate solution attempts (fixed and session restarted). Recent software changes in control software including addition of new Observatory Manager routine have seemed to have introduced bugs / and/or unforeseen side-effects.
  Fixed (CCDApp2/AstroMain)
  
• Slaved Dome began to move to a different position to where the scope is physical pointing. The Slaved Dome moved to and began operating around azimuth 70 deg +/-, whilst the real scope was operating around azimuth 190 deg +/-.  This problem also arose on the 3rd commisioning session 2018-05-10. Later investigating further shows that LST for telescope becomes incorrect in POTH.Hub  The underlying cause for this glitch in LST in still not known but the movement of the slaved Dome was later judged to be 'expected' given the information that POTH.Hub appears to have. The issue is critical and does not provide confidence for unattended operation until the underlying cause is identified and resolved. Issue managed by checking the LST times in LX200 and in POTH.Hub at start of session.  Issue eventually resolved itself fully once system moved over to using Meade Generic Driver for the Telescope and DeviceHub for Telescope/Dome Control and teething issues sorted out.
  Resolved (POTH.Hub, Pulsar Dome, LX200)

Minor Issues

• CCDApp2 Observatory Control Software issue -  Sun information. Sun information is being accessed by Observatory Manager thread every 30s which interfers with user's use of TheSky program (part fixed and session restarted).  Recent software changes in control software including addition of new Observarory Manager routine have introduced bug and/or unforeseen side-effects. Fixed.
  Fixed (CCDApp2/AstroMain)
   
• Pulsar Dome switching back and forth between USB Serial Port COM9 and COM11. Problem seemed to be related to an instability of POTH.Hub / drivers after CCDApp2 crashed and TheSky6/POTH.Hub process were closed without disconnected the Dome  Issue seems to be related to some instability / misuse of the system.  The problem was not seen in the two following sessions on 2018-05-08 & 2018-05-10.  Mitigation / workarounds implemented in CCDApp2/AstroMain which produced a workable solution. The underlying issue involving port switching eventually resolved when Observatory Computer was replaced with a new one that used Windows 11 Operating System.
  Fixed (Pulsar Dome, USB/Windows OS, Observatory Computer)
   
• Alignment of Telrad to that of the scope took considerably longer than it should.   It was difficult to align scope on a bright star by trial and error without the assistance of Telrad (not yet aligned) or a Finder Scope (not available, as its short male dovetail had been requisitoned for use by Telrad). With hindsight this alignment task might have been easier to perform during daytime using a distant terresterial object (though the observatory 5 deg altitude limit might have interferred with this).  With hindsight it would have been wise to use a dedicated star finder routine like the one in PemPro V2.
  Resolved (Telrad, LX200)
   
• Somewhat difficult to get use to the sudden sounds of slaved Dome rotating. At semi-regular intervals the dome would adjust by a degree or two to keep the shutter within the specified azimuth target (1,  2 degrees), this is difficult to get used to as it doesn't happen is response to anything that the user initiates unlike a telescope slew where it is fully expected for the dome to begin making a noise as it slews   At next session (2018-05-08) it was examined whether it was feasible to have Dome tracking at Sidereal Rate at the same time as Dome Slaving is used. However its not feasible since Telescope Slews are not recognised as having been completed by TheSky/TelescopeAPI. This will not normally be an issue , as most of the time the observatory will be used in either Unattended or Remote Controlled Operation).
  Closed (Pulsar Dome)
  
• After Parking Scope a timed out' error message was produced. On one occasion a timed-out error message was produced by TheSky/ASCOM.Utilities (See Fig 1)
  Reason seems to be that the Scope is still connected in TheSky6 but the Autostar II/Telescope API is not responding. Workaround seems to be to set  'Parked Behaviour' in 'ASCOM Meade LX200GPS/R Setup' from No Coordinates to the specific coordinates corresponding to the  Park Position.
  Closed (LX200, TheSky6, ASCOM Meade LX200GPS/R driver)

Small Defects

• None

Continuous Improvement

• None

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