2009-11-23: Having trouble with offset pointing verification. Lots of poor results.
Note offsets (of single stars in the trio usually) and drifts which mainly occur in azimuth.
Tracked a single trio for five iterations of the offset pointing script to look for (Az,El) dependence to offsets and drifts. No apparent dependence on (Az,El) noted.
Periodic Jump in Elevation Position Every 60 Seconds
Noted during seeing measurements (otherwise would not have noted a position jump with a 60 second periodicity. See the attached plot: .
Looking at actual command and response commands, appears that the ACU position is drifting for about 5 seconds or so relative to the command position. See the attached plot: .
Seeing run associated with the "Offset2" measurement did not show this periodicity, though it did show a single position jump.
Concern here is that this is problem with the tracking ability of the ACU over longer timescales than we have measured before. Would be useful to make some several-minute tracking observations (equivalently long seeing measurements) to further diagnose this problem.
Seeing measurements made today do not show periodic position jumps noted on 2009-10-02.