Palomar LGSAO Engineering Summary 11/19/05 UT

Daytime results:
1. Removed Q2 ND, replaced Q1 & Q3 uncoated B-S + ND4.0 with AR B-S + ND2.0 
2. Further testing of HOWFS timing card - could not revive it.

Night log:
1717 Laser ready, 6.75W.  Conditions photometric.
1735 Projecting in dome.  Aligning BTO.
1740 Quad cell sum signals: Q1~600, Q2~400, Q3~500 cts
1743 With polarization optimized: Q1:2300, Q2:750, Q3:7500 (Q3 ND=3.0)
1750 Adjusting focus of laser to minimize spot on LLT primary.  Final focus setting of +7.007 inches -> 95% encirc energy in 14" (visual estimate).  Installed 11" ("2-annulus") mask on LLT primary.
1820 Opening for projection at zenith.
1830 Spotters, dome not ready...
1850 IR camera not connecting to safety system.  Jumpering IRCAM.
1855 BTO shuttering beam.  Closing dome to realign BTO.
1910 Max BTO motor move necessary was 10 mum.  Opening dome again.
1911 Propagating at zenith.
1915 ASCAM shuttered due to an aircraft.  Spotters estimate it was 12-13deg from beam at the time (ASCAM avoidance radius was set to 20deg).  IRCAM was taking data (but jumpered).
1921 Focusing Acq: acq_z = 10580. FWHM=30.7 pix = 4.5"
1929 Focusing LLT: lltfoc = 5110. FWHM=27.1 pix = 4.0"
1932 Focusing Acq: acq_z = 10500. FWHM=28.6 pix = 4.2"
1937 Saving 10s integrations, V filter: llt_7 and llt_8.
1938 at NGS focus (for LOWFS background estimate): llt_9
1939 Detunned image at LGS focus: llt_10
1942 Moving to Tycho-2 2776-1115-1
1946 Saving 5s integrations: cal2_1 to cal2_4
1949 Saving 5s integrations at LGS focus: cal2_5 and cal2_6.  Preliminary LGS photometry: V=9.9
1950 Acquiring star with AO.  Having trouble registering lenslets to DM.
2000 Focus change: 57.65 -> 58.16. TT-only FWHM=1.28" -> V seeing = 1.8".
2012 Projecting at zenith again.  Beginning UTT test.
2020 Measuring 120 cts on WFS at 100 Hz.  Scattered light along edge and center of pupil appears particularly bright tonight.
2235 LGS too large to close UTT loop reliably tonight.  Behaviour eratic.
2100	Taking HOWFS pixel telemetry to investigate source of scattered light.
	1. Laser detuned, move TTM, UTT around.  Scatter only changes with UTTa
	2. Stepped llt_a linearly, looking for centroid changes.  None (big spot).
	3. Stepped ttm linearly, looking for centroid changes.  None.
2140 Moving secondary out of beam to test "leaky pedestal" hypothesis.  Results seem to confirm that scattered light is indeed coming through bottom of PF cage.
2200 Moving to V=5.4 NGS to measure seeing.
2210 Seeing is 1.3-1.6" at K, 1.7-2.1 in V
2215 Trouble-shooting pupil registration problem.
2302 Problem appears related to poor seeing.  Improving robustness of algorithm.
2310 Moving to zenith for further investigation of scattered light.
2330 Viewed secondary from primary cell.  No obvious light around 2ndary.
2340 Installed temporary bafffle behind trolley (blocks all direct light to primary and tertiary flat.  No effect on scattered light.
0005 Rotating cass ring.  Scattered light does not move!  General puzzlement.
0035 Refocusing on LGS to measure spot size.
0035 Shuttered 2 times by ASCAM lunar twinkle (moon ~30 deg. from zenith)
0040 New acq focus: 11240. FWHM=28pix (4.1")
0056 LLt focus: 5140, FWHM=26.5pix (3.9")
0100 Concluding laser operations.  Switching to NGS.
0110 Starting dual HOWFS/LOWFS test on a 10.2" separation binary (5.4/10.10)
0240 Partial success.  Procedure for turning on LOWFS TT offload worked well.  Trouble with brighter star sucking LOWFS in.
0245 Setting up for Q3 interlock timing test.
0305 Q3 interlock delay: 65ms +/- 5ms
0315 Beginning BTO open-loop pointing calilbration.
	Zenith-West, 90 to 49deg elev.  Q3 interlock triggered at 49deg.
0400 Calling night.