2009 June 04 UT Technical Night after LBC maintenance & engineering run

Observers: O. Kuhn (Tucson), and J. Hill (at beginning)
Telescope Operator: A. Ceranski

Summary of Issues

Started around 20:30 MST. Initial slew to a pointing star. I stopped it to start focus/collimation. Somehow - related or not? - we got an RPC error on the Red Science Camera. After repeatedly rebooting the CMU and finding that when we tried to restart LBC, before even turning on the filter & rotator, the Red Science Camera would say "uninitializing", we checked the redchannel.conf file and found that the windows PC was never turned off. So the reboot was not cycling power on the Red Science PC. We did this via the DataProbe. Now we could turn on LBC Red Camera.

Focus was good - dofpia 'grabbed' the first set of images, convergence was relatively quick and Z22 corrections reasonable.

Problem with maintaining the connection to LBC windows or even to windows on lbtmu03. E.g. The LBC User Interface appears to hang. I cannot type anything even in an xterm on the lbtmu03 or lbtmu05 to check processes. Click "X" on upper right of firefox and it appears nothing happens right away but soon I get a message that firefox is not responding, do I want to 'force quit' - yes kills the windows. Sometimes I still cannot type in the launching xterm.

I saw a similar problem in trying to view images - so this time not even through LBC network. On lbtmu03 via lbtssh, I typed 'xgterm' which should launch an xterm and run IRAF in it. I typed also ds9 to launch ds9. Both came up blank and did not allow any interaction.

Play-by-Play (entered after the fact, times approximate)

A listing of the images, OBname, filter and focus offsets (since most images were focus images) is here.

20:30 Load OB WT10_352 to slew to this pointing star. Stop OB so I could focus/collimate. Got an RPC error with Red channel. From the log:
2009/06/04 03:40:41.261335 E R CAMERA            RPC Client/Host communication failed retval:5 [src/camera/camera.c:820]
2009/06/04 03:40:41.261478 E R                   camera system encountered a problem
2009/06/04 03:40:41.261596 N R                   >>> stop completed
2009/06/04 03:40:41.261888 N -                   UI update with message >(RED Channel) one or more systems failed: (CAMERA) RPC Client/Host communication failed!< at 1244086841.261651
2009/06/04 03:40:42.232281 W -                   TCS IIF_GetMultiParameter error: ERROR: No such command. [src/tcs/tcs.c:297]
2009/06/04 03:40:43.271378 N -                   Stop signal to IIF functions removed

Turn camera off/on repeatedly, but this does not clear the RPC error. Just after we turn on all systems, they read "initializing" and Red Camera status suddenly changes to "uninitializing", before any of the filters or rotators are even ready - this is not the normal sequence, as usually errors on the trackers & cameras are reported after rotator & filters are ready.

Finally we notice that the redchannel.conf file was modified the night before. And it has a few new lines, among these:
Camera.WindowsPCPowerLine      =,15  # emulated if :0,15 or sw switched if :3,150
So it looks like the windows PC is always on and no longer controlled by SW.

Rebooted the Red Sci PC via the DataProbe. Finally Red Camera came up.

23:30 Checking Pointing correction algorithm on 4 stars:
  • WT10_328 RA=15:40, DEC=37:31 LST = 16:06, star is in NW. Works OK - ptadjust1 sends correct CA, IE to move star toward rotator center
  • ACT0345 in NE. OK
  • ACT0198 RA=19:14 DEC=-01:08 LST=17:49, star in SE. OK
  • ACT0398 RA=17:33 DEC=67, LST = 18, star inSW. OK

01:50 Measure filter focus offsets. Does the addition of Z22 to dofpia improve stability/consistency of measurements?
  • Slew to star field at RA=19, DEC=50. Elev=71deg

01:55 RV_rV_superfoc: bestfocus results are:
  • for r-SLOAN: 0.138 fwhm=2.01
  • for V-BESSEL: -0.074 fwhm=2.74
  • for i-SLOAN: 0.0816 fwhm=2.02
  • for g-SLOAN: 0.073 fwhm=2.85

*continuing superfoc sequences at rV and ig. Table shows results: bestfocus fwhm:

filter best-focus (mm) fwhm comments
r-SLOAN 0.138 2.01  
V-BESSEL -0.074 2.74  
i-SLOAN 0.0816 2.02  
g-SLOAN 0.073 2.85  
i-SLOAN 0.014 2.12  
g-SLOAN 0.028 3.23  
r-SLOAN 0.123 2.24  
V-BESSEL -0.043 3.13  
i-SLOAN 0.0147 2.11  
g-SLOAN 0.043 3.21  
r-SLOAN 0.130 1.91  
V-BESSEL -0.047 2.73  
r-SLOAN 0.128 1.91 092002
V-BESSEL -0.0476 2.62  
i-SLOAN 0.0385 1.93  
g-SLOAN 0.046 2.65  
r-SLOAN 0.141 2.01 093937
V-BESSEL -0.058 2.51  
i-SLOAN 0.085 1.84  
g-SLOAN 0.056 2.66  
r-SLOAN 0.176 2.32 coarse 0.08mm grid
V-BESSEL -0.116 2.41 coarse grid 100929...101206, look at first 2 images in sequences - residual spherical?
i-SLOAN     coarse grid
g-SLOAN 0.0559 2.48 coarse grid
r-SLOAN 0.128 2.28 back to fine grid
V-BESSEL -0.062 2.59  
i-SLOAN 0.07 2.06  
g-SLOAN 0.047 2.56  
extra/intra focal pair 110102 and 110134 are extra-focal images of pair
r-SLOAN 0.1427 2.11  
V-BESSEL -0.05 2.56  
r-SLOAN 0.139 2.12  
V-BESSEL -0.03   flat
extra/intra focal pair 111925(B) and 11959(R) are extra-focal images of pair
i-SLOAN 0.078    
g-SLOAN -0.018 2.54  
r-SLOAN 0.126 2.20  
V-BESSEL -0.036 2.56  
i-SLOAN 0.06 1.61  
g-SLOAN 0.016 2.62  

A few comments and questions:

  • many of the trends were not well fit by a parabola - perhaps because seeing was so tight that the stars were undersampled.
  • but then, shouldn't the coarse grid given better results. Need to re-visit those 4 sequences.
  • Look at the first images of the coarse grid sequences. There are halos around the stars - isn't this a sign of spherical?
  • Can the extra/intra focal pairs be analyzed to look for aberrations? How do the two sets, each taken after a focus/collim check, compare?

-- OlgaKuhn - 04 Jun 2009
I Attachment Action Size Date Who Comment
daq.20090604.gifgif daq.20090604.gif manage 48 K 08 Jul 2009 - 22:48 JohnHill Plot of Telescope and Mirror Temperatures
Topic revision: r5 - 08 Jul 2009, JohnHill
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