With dome lights on and mirror covers closed, exposures are taken in the J filter; the camera is aligned when the signal is at a minimum as then the camera is looking directly at the covers and not getting light reflected off the dome. 1. IN THE DOME:
Turn on all lights (top and bottom levels); make sure that if peple are around they will not affect the light path to the camera; remove the window cover from the camera (IRCAM has a screw on cover on its snout). 2. IRTSUN1, TELESCOPE STARTUP:
Run up telescope with tel_dev (not _sim), datum dichroic and move dichroic to appropriate port for camera (east for IRCAM, west for UFTI) by “pstart”, and e.g. “port west”. Keep mirror covers *closed*. 3. KIKI, INSTRUMENT STARTUP:
If using UFTI datum filter wheels and shutter and open shutter (if not already run up, run up the EPICS screens to do this by “dm ufti.dl”). Run up oracom for skl/oractest and send “ufti_align” for execution.
If using IRCAM set up for the Vax keyboard mapping (see instructions given on typing “runup”), open a vaxterm on irtcon, and run ircam3_eng. If you prefer you can take data through orac in which case run ircam3_dev and then run up oracom for skl/oractest, send “ircam_align” for execution. (Its better to use orac if you also want to e.g. take and analyse array test data.) 4. KIKI AND IRTSUN1, TAKING DATA, MOVING DICHROIC:
If using UFTI run the ufti_align sequence which takes 10 sec full array exposures with the J filter. (Exposure time may need tweaking.)
If using IRCAM and _eng, use “direct_configure” in the SMS menu to select the J filter and set exposure time to 10 seconds, NDSTARE, standard bias, full array. Hit “run” to take a frame. If using _dev and orac, run the ircam_align sequence from oracom. (Exposure time may need tweaking.)
The routine is: take an exposure with dichroic at 0,0; move dichroic, when dichroic is settled, take another exposure. There is some hysteresis so move the dichroic from positive to negative values, or always go through (0,0) (no need to actually take repeat data at 0,0, just set the dichroic there). The command is e.g. for moving port, “poffset 0 -50”. Tilt offsets are smaller than port and a sequence may look like:
tilt: 0 0 0 0 0 0 0 0 0 0 0 0 0 port: 0 -50 +50 -100 0 -150 -200 0 -250 0 -300 0 -400
set to minimum signal value e.g (0,-190), then cycle through tilt:
tilt: 0 -20 +20 0 +40 0 +100 -80 +70 -60 +100 port: -190 -190 -190 -190 -190 -190 -190 -190 -190 -190 -190
set to minimum signal value e.g (+15,-190), take another frame to check for low signal. 5. KIKI or KAUWA, ANALYSING THE DATA:
If taking data from the OM you can send the data through QUICK_LOOK in the DR so that NDF’s are created as opposed to HDS files. These are a little simpler to display and get stats on, but its not crucial to do this. Set the DR going by typing “oracdr_ufti” or “oracdr_ircam”, then “oracdr -loop flag”.
If using UFTI the data will be in /ukirtdata/raw/UTdate/ufti, or if you ran the OT script and QUICK_LOOK you can use /ukirtdata/reduced/UTdate/ufti.
If using IRCAM and _eng the data will be in /vaxdir/ircam_data/engUTdate/rodir. If you used _dev and orac then it will be in /ukirtdata/raw/UTdate/ircam or /ukirtdata/reduced/UTdate/ircam (if QUICK_LOOK ran).
cd to the appropriate directory. Type “kappa”. Get a clipped mean value for each full frame as it comes in by typing e.g.
for UFTI data: "stats clip=3 f20001216_00014.i1" for /raw or "stats clip=3 f20001216_00014" for /reduced for IRCAM data: "stats clip=3 ro001216_14" for _eng data or "stats clip=3 i20001216_00014.i1" for /raw or "stats clip=3 i20001216_00014" for /reduced
Plot the mean value against port or tilt offset and get a minimum by linear extrapolation from the outer points to center, or by fitting a parabola. The data will look something like: