Telescope and AGw Commissioning at LFBG with IRTC - 23-24 April 2009

Observers: A. Rakich, M. Pedani and J. Hill(Tucson), J. Heidt (@LBT)
Telescope Operator: A. Ceranski
Software Support: M. DelaPena plus N. Cushing, C. Biddick (phone) Telescope Support:


Lost 2.75 hours to observer error. Had not realized that guide difficulties were caused by accidentaly sending the presets in parallactic mode and assumed that the new software build was at fault. Experienced numerous shifts in pointing throughout the night. The range of elevation change was ~ 5X the range of azimuth change. Finally got an (incomplete) set of astrometric measurements in 1"-2" seeing on BS9152, hopefully will get some first indications from that. Closed at 1:36 for wind and remained closed for rest of the night.


TCS Build 25 installed on mtn


7:40 preset to M5_0269, no star, hunted in elevation, found the star 40" off, old (default) IE -70 CA -69 new IE -10 CA -78 (This was significantly off, but less than LBC was off last night.

7:43 preset to M67astrom gs0 ACTIVE mode ; too much defocus, send 6000 nm in Z4 on the M2 before John points out that this is the slow way, send as global offset -0.5 mm Z, much better focus, now going to collimate on GS 35 (as on-axis star in M67 is too bright).

7:50 collimating on gs 35, preparing to take astrometric field for Jesper. Problem with guiding, the star gradually drifts out of guide window, seemingly getting small guide corrections to the wrong place as it does so. Michele looking into it. Going back to M67astrom GS0 in Acquire mode it seems that we have lost our pointing as well, so going back to M5_0269 to reset pointing.

8:03 strangely the M5 star was reasonably well centred. Going back to M67 GS0 in acquire mode. reset pointing IE=8 CA -65

8:10 preset to GS 35, star lands on hotspot on acquisition, however gradually drifts off with our new guiding problem. Going to GS 0 in acquire mode to watch tracking for a few minutes.

8:20 after ~8 minutes of tracking drifted about 1.5" so tracking is looking ok. resending preset to GS 0 in active mode. Guides well on axis, offset telescop in IE and CA and guiding brings it back.

Go back to GS 35 with PA 0 and it doesn't guide (well it seems that it does guide but to the wrong point, and that point slowly drifts out of shot to the lower left).

Various telephone/polycom conversations with Norm, Michele, Chris, John, Andrew, Marco, Olga in a number of permutations.

21:00 pointto BS9152 gs=0 ACTIVE


Preparing to rollback from Build 25 to Build 23 which is the last build used on sky with GCS.

GCS or something (OSS?) seems hung in some unknown way.

21:05 stopAGW / startAGW but that didn't help. Abandon this attempt at collimation in favor of rollback.

21:12 Rollback to B23 unpatched by Michele.

21:48 Rollback complete except for irs.

21:55 Presets didn't go through, so had to switch versions of irs

Build 23 unmodified

22:00 pointto M67astrom

22:04 pointto M5_0269 gs=0

22:05 pointto M5_0619 gs=0

22:08 pointto M5_0460 gs=0 ACQUIRE - Adjust IE=-100 CA=-84 M2Zglobal=-1.0

22:24 pointto BS9152 gs=0 ACTIVE - didn't find a star

22:29 pointto some M5 star - found where expected with lots of coma at EL=52. Why does changing the build change the coma?

22:44 pointto BS9143 gs=18 in Position Angle mode AND note that this was the problem. pointto was sending everything in parallactic mode.

Aside from wasting a couple hours, we learned that the telescope apparently can guide in parallactic angle mode - at least until the star drifts out of the guide box after a few minutes.

Build 25 returns

23:14 pointto BS9143 gs=0 ACQUIRE - no star found

23:17 pointto WT10_239 gs=0 ACQUIRE - Adjust IE=-82 CA=-67 M2 Zglobal =-0.6

23:24 pointto BS9143 gs=0 ACTIVE - star found, athough not perfectly centered. Seeing has degraded to 2 arcsec at EL=42.

23:32 pointto BS9152 gs=0 ACTIVE

23:34 pointto BS9152 gs=0 ACQUIRE PAM- IE=-72 CA=-76

23:37 pointto BS9152 gs=0 ACTIVE

23:48 John stops logging and Andrew starts making a log.

23:55 Marco presets to StoneMagw gs 0 in acquire mode, no GS, so go to nearby pointing star and adjust pointing IE=-92 CA= -60

00:06 preset to GS 0 of stone field again, collimate for a bit... find this field is too low at this time of night, decide to get smaller dataset on BS9152 at a few different position angles.

00:18 go to BS9152 GS0, no star in field, going to pointing star nearby (WT10_376) and adjust IE= -76 CA= -71

00:25 go to BS9152 gs 0 collimate

AGW Transform data

00:31 go to BS9152 gs15 0 collimate; PA=66.77 Seeing ~1.5"

Hereinafter PA =66.77

00:36 takeseq 2 15 gs15

00:39 go to BS9152 gs14 takeseq 2 15 getdat

00:42 go to BS9152 gs10 takeseq 2 15 getdat

00:45 go to BS9152 gs 7 takeseq 2 15 getdat

00:49 go to BS9152 gs 8 takeseq 2 15 getdat

00:52 go to BS9152 gs 12 takeseq 2 15 getdat

00:56 go to BS9152 gs 16 takeseq 2 15 getdat Seeing ~1.3"

01:00 go to BS9152 gs 11 takeseq 2 15 getdat

01:02 go to BS9152 gs 13 takeseq 2 15 getdat

01:05 go to BS9152 gs 18 takeseq 2 15 getdat

Hereinafter PA =46.77

01:09 go to BS9152 gs 18 takeseq 2 15 getdat

01:11 go to BS9152 gs 13 takeseq 2 15 getdat

01:14 go to BS9152 gs 11 takeseq 2 15 getdat

01:17 go to BS9152 gs 16 takeseq 2 15 getdat

01:20 go to BS9152 gs 12 takeseq 2 15 getdat

01:24 go to BS9152 gs 8 takeseq 2 15 getdat

01:28 go to BS9152 gs 7 takeseq 2 15 getdat

01:30 go to BS9152 gs10 takeseq 2 15 getdat Seeing ~1.1"

01:33 go to BS9152 gs14 takeseq 2 15 getdat

01:36 go to BS9152 gs15 NOT DONE ! Clouds thicker, wind may be close to 20 m/s ; We decide to close.

-- AndrewRakich - 24 Apr 2009
Topic revision: r9 - 25 Apr 2009, JohnHill
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