UT 26 Aug 2020 - Night #5 of Restart

OSA: S. Allanson

ISp: E. Solheid

Mtn Manager: L. Durham

ISA: O. Kuhn (Tucson)

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PROBLEMS

1. Lost at least an hour or more due to /newdata running out of space. For future, even during restart, IA2 is strongly encouraged not to move data in/out of /newdata during nighttime operations.
2. Spot seen on LBC-R (r-sloan) but seems to have vanished during skyflats - check filters or lenses?
3. IT 6386 - MODS2B Sequencer - all sievesnaps at start of night affected, but seems to have abated durng on-sky - need to check exposures to verify it did not return. Has occurred of night each night.

PROPOSED PLAN OF ACTION:

• MODS
  
  • Basic Checkout
    • Observe a standard star in all modes (30-45 min for 3 images).
      • Repeat if clear, otherwise take specstd for any modes used during the night
    • Dice-5 imaging offsets
      • Dumbell Nebula (first half)
      • M76 (2nd half)
  • Test Science OB
    • Sidereal
    • Non-Sidereal
  • Spectrophotometric standards (only if clear)
• LBC- Red
  • DOFPIA / doHybrid - colliimatie on sky
  • Test Images
  • Rotator Center
• Mixed mode MODS-1/LBC-Red tests
• LUCI-2 (if released for on-sky)
  • Dectector Rotator
  • Rotator ZP (Longslit method - see OT and J.Power's notes)
  • Imaging Dither Test

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Summary:

We obtained sufficient data to release MODS for science and got a start with LBCR.

We started with binocular MODS, and:

• observed a spectrophotometric standard,
• a science-like imaging sequence,
  • with async 45", 45" dithers (which required turning off the copointing check but ran well, save for one trailed pair of images
  • with sync offsets instead (which failed on at least two occasions when the asynchronicity between the 2 MODS exceeded the 60-sec timeout; see existing IT 6939. These observations only confirmed the recommendation not to use syncoffsets in imaging scripts.
• ran a dithering sequence with the pointing mask to check the alignment of the DETXY coordinate system and mask
• ran a long-slit observation (of PN NGC40).
• observed a NS target
• and then, as it appeared clear on the all-sky and the guide flux was stable (but note that there was significant haze! not to mention the many clouds earlier in the night), we
  • observed an photometric field in dual, blue and red-only imaging modes
  • observed a second standard star in all modes

Around 10:30 UT, we reconfigured MODS2-> LBCR and started to checkout LBCR with:

• superfoc sequences
• data to measure the rotator center
• a science-like OB that dithered and guided

Issues:

We had a few issues:

MODS2B --- the first 7(!) sieveSnaps showed evidence of sequencer issues, but the remaining 80+ images were all good. IT 6836

newdata -- filled up during the night, a consequence of the work to resolve data flow to Repository (IT 8160)

The LBCR images through at least 3 filters showed a spot near the rotator center, but when I took sky flats through these same filters, and more, I saw no such spot. Was it a transient moth on the dewar window that flew away when we slewed? We observed 3 fields - I'll have to compare, but the sky flats show no evidence of dust or debris on the dewar or filters used (R, r, i, z, Y, F).

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Log:

Times are in UT.

01:35 Ran up both MODS, woke them and took sieveSnap images. modsNc.20200826

First 5 mods2b images affected by sequencer issues. 0/5 good images.

01:45 Powered off/on HEB and did a quit,"ic" on m2.bc

01:50 Another two sieveSnaps 0006 and 0007 Again the mods2b images are bad.

02:09 Twilight sky flats on blank field 16+55:

• Dual
• 1K test, 0008. 1-sec at g and r. m1r: 15k, m1b
• execMODS --modsN -e gr_skyflat_obs.txt
  • 3K @ gr 0009-13
• execMODS --modsN -e gi(2)_skyflat_obs.txt
  • 3K @ gi 0014-
  • some stars are appearing on this set, but the flats are dithered.
• Note - on the flats, mods2b is not showing the sequencer issue, but it can be hard to pull out of the flat field as we have seen recently for mods1r.

02:33 Going to the spectrophotometric standard, BD+33

• Collimation/focus:
  • GCS is unable to write to Repository, IT 8169
  • Steve called Igor who is calling David E. They are working on it.

03:19 Steve is closing, since the 25-mic particle count went up above the closing limit.

03:35 Igor called back and said that David was able to reset permissions. We are testing it.

• First, gcsclient readGuideCam left -e 1000
  • image appears in /lbt/data/share/tcs/lbto.20200826/left_guider00001.fits
  • but the image taken this way doesn't go to Repository
• Second, Steve sent a test preset. It worked! David added a note to IT 8169 - sounds like he has resolved the problem for now, but more investigation is needed into why the NFS mounted Repository.

03:40 Steve is opening again. There are clouds, but all but sub-micron particulate counts are below their respective thresholds.

03:54 Back to BD+33:

• Collimation/focus
• acqBinoMODS bd332642.acq (19)
• offsets made:
  • mods1: -0.699 11.748 rel
  • mods2: 3.434 8.282 rel
• confirmatory thru-slit (20) look ok but a tad to the right
  • tweak using modsAlign - r on 0020
    • mods1: -0.312 0.104
    • mods2: -0223 -0.295
  • confirmatory thru-slit (21) looks better, but still the star is a bit right of center. Guide star is faint, ~15, and we have clouds and moonlight - perhaps this is a guiding issue?
• execBInoMODS bd332642.obs
  • We are looking through clouds. Seeing is good, 0.77" on the guider.
  • So far, so good with the MODS2B. The only bad images were the first 7, all sieveSnaps.
  • < ~09:54-09:55MST lost guiding. On Dual Prism.
  • 10:01 - lost guiding again.

05:19 5-pt dither imaging script with offsets test, active mode:

• execBinoMODS Dumbell_Nebula_Img_active.txt
  • 0.5" seeing
  • Error copointing limit 45", 45". Aborted.
  • Steve disabled the copointing check and we are repeating the script. It is working fine.
  • clouds causing the guide star to fade in and out. 05:45
    • mods1: after one offset, the offsetxy command timed out after 60-sec. Retry resumed but next image is streaked, mods1r 0039 and mods1b 0036.
    • mods2, at same time, slightly different error msg: no guide star found. Retry was ok for that side.

05:45 Repeat script but this time with syncoffset before each offset command. Let's see how things go as the 2 MODS get out of sync... We got a timeout error

execBinoMODS Dumbell_Nebula_Imct_sync.txt

MODS2 errors: bc syncoffset offsetxy 45 -45 absError: Command 'OFFSETXY 45 -45 abs' timed out after 60 secAbort, Retry, or Ignore? rRetrying command 'OFFSETXY 45 -45 absOFFSETXY 45 -45 abs

But I think that led to a stray sync flag

We had another timeout error on MODS2 on the offsetxy -45 45 abs

06:22 Longslit observation of PN NGC40

• acquisition
  • MODS1: 49 & 50, offsetxy -0.606 10.970 rel
  • MODS2: 50 & 51, offsetxy 3.913 7.314 rel
• execBinoMODS NGC40.obs

06:35 We ran out of disk space in newdata. Barry called Igor. Meanwhile, we continued taking spectra which appeared in modsNdata but only one (mods1r.20200826.0052.fits) in newdata.

06:55 Clouds - it's very overcast. Steve reports that he cannot see stars.

07:00 Igor made a new directory on Repository in which to temp store the files in newdata.

07:40 Newdata has more room now and we are moving on. NS target has a name that is not coming up in the NSIGUI (P29/Schwassmann-Wachmann 1), so we're doing something else while searching for alternate names.

07:45 M52 dither with pointing mask (to measure DETXY alignment with respect to mask alignment).

07:59 blue fitsflush

08:15 ~20 on each channel

08:15 NS test on Comet 29P/Schlassmann-Wachmann 1

• execBInoMODS comet.img.txt
  • some scattered light from nearby star
  • guiding and WFSing is OK

08:45 Photometric Imaging field L92 in Strip82. It is not strictly photometric, but it is clear.

• execBinoMODS L92dualim.txt
• execBinoMODS L92redim.txt
• execBinoMODS L92blueim.txt

09:20 Spectrophot Std Feige110

• mods1r 86: -1.026 11.944
• mods2r 90: 3.277 7.966
• confirmatory images again to right. m1r by -0.16 and m2r by -0.4
• observation: execBInoMODS feige110.obs

10:30-10:45 Reconfigured from MODS -> LBCR

10:45 Slewed to M76 for focus/collimation. That took a long time - 8 iterations. Seeing is very good and stable, but there was coma (z8) that WRS did not remove and the first 2 FPIA iterations were on focus only, giving -15276, then 9788. Then it added 2344 nm z8.

11:12 Superfoc

• PA=0
• PA=180
• PA=0
• Near the rotator center, there is a dust spot. (r-SLOAN)

11:29 Rotator Center measurement at 1h50d field

• PA=0, 180, 90 and then 270

11:40 Science-like exposure

• ptautoadjust (I forgot to collimate, but we had not moved far and collimation looks good)
• run series of dithered, guided exposures at z, i and R.
• In all of the LBCR images so far, taken through 4 different filters (r, z, i and R), there appears to be a spot near the rotator center.

12:06 Sky flats (although we'll need to clean the dewar window for real flats)

• i-SLOAN: skyB~16 - bit dark still.
  • starting these at 12:17 or so and using 3-sec. The i-SLOAN flats don't show the dark ring... 121654.
• r-SLOAN 12:19 skyB~14.5, 1-sec. The spot is gone here too...
• R-Bessell - one flat below saturation but the spot appears to be gone
• Y - 10k counts at 12:30, no spots
• F972N20 - newdata filled up again. I continued the script, but will have to look for the flats later or on the PC.

12:38 Steve is closing up.

• I turned off the LBCR (LBCB was OFF)
• I put both MODS to sleep.

-- BarryRothberg - 25 Aug 2020