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How to operate IMACS

The camera parameters for imacs should be the default, but in case they are lost, restore them as follows:


In the TCS:
rcfg 0
cn 1
pf 1
sz 86
cn 2
pf 1
sz 86
cn 3
ca 133
pf 1
sz 95



hrc01, hrc02, hrc03
flip          no
flf          40.0
arcsecperpixf 0.232
deltaf        23.1
initppixf     207.0
n2            13
tableratio    0.8664

hrc02 only
toffaxis      yes
fitpc          no
offaxpcscale     0.0 
offaxcomascale   0.0
offaxastigscale  0.0

Operational procedures:


It is better to run IMACS with the rotator servo enabled.

Set "sh 1" in all three gcams.

It is no longer necessary to exit the GPC program when running IMACS.
It is no longer necessary to run the script, gpc2imacs.csh
(It is run automatically from a crontab.)

You must measure the angular offset between the rotator and IMACS every time it is reconnected to the rotator.  To do this, set IMACS to its "nominal" position using the procedure documented by the IMACS team.  Then read the rotator encoder position on the VANE END computer.  It should be a number like -46.250.
Edit the value of IMACSCHUECO in the operator's AND the observer's ~/.cshrc file to reflect this number.
In mgtcs.tcl, use EQU mode and a rotator offset angle equal to 90.0 + IMACSCHUECO.  It should be a number like 43.750.

If IMACS is not being operated on the computer, "llama", edit the value of IMACSMOTORS in the operator's ~/.cshrc file.

To make a new template of camera 3, install the LED and run "newtemplate" as usual.  Guess where the lower left spot
should be.  Remove the LED and measure the pupil center and enter in hrc03 as usual.  You will probably want to run the camera 3 active optics on a computer other than the operator's.  See the procedure for running two active optics systems in parallel.

To make a new template of camera 2, first run the active optics with camera 3, guiding with camera 1 if possible.
After the active optics has converged, use "newtemplate" with camera 2 as usual, and measure the pupil center as usual, entering its value in hrc02.
The aperture center must also be entered into ~/egmap.dat as the parameters, pcentx2 and pcenty2.

If you shift active control from one active optics computer to another, you *must* do a "resetcell" in both systems, before proceeding.  Failure to do so may put more than expected forces on the mirror.

How to make a good stellar template for imacs camera 2.

  •  - Use a noise free camera.
  •  - Wait for good seeing, no clouds, no moon.
  •  - Wait for the mirror temperature to stabilize.
  •  - Use a bright star but not too bright.  (~ 11th mag.)
  •  - Use an unvignetted image.
  •  - Guide with camera 1.
  •  - Use tf 10, avf 30; wait 300 seconds, and then send.
  •  - After newtemplate, edit out bad points with tvmark inter+

 

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