20170111

On-sky engineering:

Calibration of OWFS using either CWFS NO closed loop control

Purpose: We want to calibrate the OWFS using CWFS (depending on what stage of the testing we are in, Feedback from Hanshin) on a sidereal trajectory at one of the following Az:

a normal star for Az 234, 292, 180

• setup on an 11 mag star on the IHMP near the beginning of the track
• move all 4 guide probes to the correct RA and DEC positions from gstar or shuffle. NOTE: because of he recent FPA work you might need to alter gstar or use shuffle_config_matt2
• save probe positions in the RA log with /home/mcs/astronomer/caldwell/shoprobes
• offset telescope and probes by the amount to get to CWFS: syscmd -T 'offset_trajectory(dx_ang=-5.5, dy_ang=-1.0, adjust_probes="true")'
• move the guide probes so that the guide stars are well centered
• guide with either GC1 or GC2
• get decent focus and then check and correct any GROC
• Retract ACAM and put in CWFS
• null out the X, Y, Focus, Theta, Phi from CWFS
  • To make X or Y offsets you will need to:
    • open the loop on the guider
    • make your offset with the handpaddle
    • clear the fiducial
    • watch as new fiducials are set to see if it looks good
    • close the loop on the guider
  • To make the Theta and Phi offsets you will need to:
    • open the loop on the TTC
    • make your offset with the handpaddle
    • clear the fiducial
    • watch as new fiducials are set to see if it looks good
    • close the loop on the TTC
  • The X and Y prescribed corrections are between -1 and 1.
  • The Theta and Phi prescribed corrections are between -10 and 10.
  • The Focus prescribed correction is between -0.05 and 0.05
• make small offsets with the OWFS1 and OWFS2 to get the lenslet centered.

To move the wfs probes:
syscmd -T -v 'WFS1_offset_probe( dx_ang=1.0, dy_ang=0.0) '
syscmd -T -v 'WFS2_offset_probe( dx_ang=0.0, dy_ang=-0.5) '
The coordinates are in units of arcseconds.

• save probe positions in the RA log with /home/mcs/astronomer/caldwell/shoprobes
• once you have both WFS and CWFS within 1.5" of nulled out switch from 5 second exposures to > 15 second exposures but do not saturate.
• save at least 15 images (at the same time) with all cameras that are running: GC1, GC2, WFS1, WFS2, CWFS, TT NOTE: This can be done one jove terminal as startsaving followed by stopsaving but best to make sure!
• wait 10 minutes
• null out corrections on CWFS
  • NOTE: if you need to make X and Y offsets you should probably do this with a trajectory offset with probes=true to keep the WFS1 and WFS2 well centered
  • e.g. syscmd -T 'offset_trajectory(dx_ang=0.0, dy_ang=-0.3, adjust_probes="true")'
• check GROC, make correction is required ( > 500 um correction)
• null out corrections on CWFS again if required
  • The X and Y prescribed corrections are between -1 and 1.
  • The Theta and Phi prescribed corrections are between -10 and 10.
  • The Focus prescribed correction is between -0.05 and 0.05
• save at least 15 images (at the same time) with all cameras that are running: GC1, GC2, WFS1, WFS2, CWFS, TT
• repeat the last 5 steps until the end of the track.
• Close the PFIP shutter syscmd -P -v 'CloseShutter()'

Repeat test: choosing a new star at the next Az in the list: 180, 234, 292.

• For each test, please note the star and end time.

CWFS+WFS Loop Control Tests

• Make sure your stack is pretty good (RSE < 250)
• Make sure GROC is pretty well set
• Select a 11th mag target near the start of the track for all probes and targetted on IHMP using shuffle and shuffle_config_matt4
• Setup on IHMP
• Center up both guide probes and start guiding on one of the guiders
• Set Exposure times for CWFS, WFS1 and WFS2 to about 5 seconds to assist in centering.
• Offset to CWFS using syscmd -T 'offset_trajectory(dx_ang=-5.5, dy_ang=0.0, adjust_probes="true")'
• Tweak up the position on the IHMP using further offset_trajectory commands.
• Center up both WFS using mgp -grid or mgp -poff. See mgp --help. This requires "Process Images" to be checked.
• Null out focus on WFS1. NOTE: WFS1 seems to perform better than WFS2 at the edges of the track
• Start metrology loop and Activate the loop on WFS1.
• Increase the exposure time for the CWFS, WFS1 and WFS2 to greater than 20 seconds for data taking but do not saturate.
• Hit "store images" and "Start Metrology Loop" for GC1, GC2, WFS1, WFS2, TT, CWFS, DMI (although there are no images for DMI)
• Monitor the WFS1 and WFS2 to make sure the X and Y positions do not exceed 1.5". If they do then make a correction.
• Run until the end of the track.

Repeat test: choosing a new star at the next Az in the list: 180, 234, 292.

• For each test, please note the star and end time.

Magnitude limits for CWFS, OWFS1 and OWFS2

Purpose: This is to come up with the minimum star magnitudes and optimal exposure time ranges for each wfs.

• Must be clear for this test
• Select a star of known magnitudes (preferably from the SDSS catalog or at least in a SDSS field
• run do_shuffle on the field and see what magnitudes have been selected for the WFS1 and WFS2.
• record the RA and DEC for the OWFS probes.
• look at the shout.probestars and report those stars and magnitudes (I think there should be 5 magnitudes for viable SDSS fields).
• setup on the field on the CWFS and WFS as done in the previous tests.
• near the center of the track please save images with CWFS and WFS with exposures of at least 15 seconds but not saturated.

Repeat this test with several stars with different SDSS CWFS target magnitudes (11th, 12th etc)

Closed dome or cloudy tests

Gain for cameras

Purpose: The purpose is to determine the gain of CWFS and PV

Procedure:

• Put in the FCU.
• Turn on a lamp (try the ldls first)
• Open the ldls shutter for several minutes
• check flux levels in the cameras.
• take five exposures with each camera.
• change to a longer or shorter exposure times and take another sets of five.