NAOMI DE CHECKS

The following is a basic check procedure for NAOMI, to be used by the Duty Engineer as routine afternoon checks, during a run period after the first night of observation.
For pre-run checks, between runs or on the first day of a run, or in case of trouble, for example if the image quality has degraded and the DM needs proper flattening, please refer to the detailed NAOMI readiness check-list.

List of abreviations (or names)

• DM: Deformable Mirror

• SG: Strain Gauge (for the control of the DM segments)

• FSM: Fast Steering Mirror

• NCU: Nasmyth Calibration Unit (slide with pinholes, calibration lamps and AG3 camera)

• OAP2: Off-Axis Paraboloid number 2

• OAP1: Off-Axis Paraboloid number 1, it’s in fact the FSM

• WFS: Wave Front Sensor

• OMC: Opto Mechanical Chassis (associated mostly to the WFS)

• USP: Universal Science Port, to which OASIS is attached. By extension, mechanisms on the optical bench

• FISBA: brand of the interferometer used for mirror flattening
  

• In GRACE
  • Mirror covers
  • Temperature and Humidity conditions
  • Fisba PC
  • Switching from L3 (Tip-Tilt) to CCD39
    

   

• In the WHT Control Room
  • Detectors (cameras) sanity checks: actions at the whtics observing system (Taurus)
  • Image quality checks: actions at the AO console and Taurus

• Temperature and Humidity are seen from the display either below the Met display in the Control Room or in Grace Electronic Room. Humidity should be maintained above 30% (too low it makes the piezo-electric SG unstable). Steep gradients in T or %RH are especially bad for DM stability.
• Check in Grace if the de-humidifier tank needs to be emptied
• Depending on conditions start-up the humidifier (only a few hours autonomy with full tank)  

• If it’s not already done, take out all mirror covers (access from two places: around the DM are the covers for the DM, return Flat, FSM, Fisba small return flat, Fisba; between OASIS and  INGRID is the OAP2 flat). Place the covers in the dedicated plastic rack, on the wooden table next to the flat screen. 
  Note: from February 2007, new optical components for GLAS have been added between the large Flat and the Fisba return flat. Only the dichroic is in the beam and to observe with Naomi only, its covers have to be removed.
  

  

  View of the NAOMI bench for acces to the DM, return flat, FSM, Fisba and Fisba return flat

Where to store the mirror covers

• Reboot the Fisba PC (simply “Restart” from keyboard). After the program has started, adjust the zoom to 3x to better see the window showing fringes (click on upper left corner of that window for menu).

   

  View of the Fisba PC (to the left of the entrance in GRACE electronics room)

   

  

  How to adjust the size of the interferogram window

• If it's not the first night of an AO run, and the instrument in use is OASIS, chances are NAOMI has been used in Tip-Tilt only mode. This means that the WFS in use is the Low Light Level (L3) and the signals to the FSM are not transmitted by the C40 processors, but by the new Tip-Tilt PC. But for the checks, you need to switch back to the old system, using CCD39 and the C40's. This implies several actions:
• In the electronics room, switch off the L3 SDSU, switch on the CCD39 (MASTER) SDSU
• In the electronics room, switch off the FSM controller.
• In GRACE, open the door giving access to the back of the electronic racks. Switch from CCD39 to L3 or vice versa (well-labelled switch on small box close to the FSM control rack).
• In the electronics room, switch on the FSM controller. 
• In GRACE, move the metal slide below the front of the WFS camera. It has 4 positions (see label on top of WFS box). The slide is fairly stiff. It seems to click firmly into place, but if the WFS display looks odd, try moving it out and back in again. 
• Another action will be needed in the control room to refocus the camera (as L3 and CCD39 don't share the same focus position)
  
• Back to Summary

  In the WHT Control Room

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At the WHT instrument-control screen (taurus)

• It’s important to start the observing system with at least one AO camera (Ingrid or OASIS) in the configuration file, because in this way all the servers start automatically (like oasisserver).
• Allways needed are AG7 (the simplex camera) and AG3 (the acquisition camera). The instrument cameras can be MITLL3 (for OASIS) or INGRID (or both at the same time: check the observing schedule or ask the support astronomer).
• Take bias runs on each of these detectors and examine the noise with Iraf
  
  Back to Summary
  

At the NAOMI control screen: AODISPLAY

AODISPLAY is a pc which allows to emulate a unix session (via Exceed) either to Navis or lpss42. The left screen is an 8-bit display and reserved for topgui; the right screen is a 24 bit display and allows to launch more complex (and modern) mimics or gui's. If the AO system has been in use on the previous night, it shouldn't be necessary to log on (as naomi) again.

From AODISPLAY right screen:

• telnet to Taurus for a session as whtobs then type obssys,  answer 1, 1  (but don't start the observing system!)

• Run the oasisgui: startoasisgui ; if everything is in error it’s probably a server problem, which shouldn’t happen if the observing system has started properly on Taurus.  The command startoasisserver will give an error if the server is already running.
  
  
• From oasisgui USP page float the bench (it takes 5min to stabilise); move the NCU to simplex position. Disregard the ADC error status (ADC is not commissioned)

  

  oasisgui USP page

   
• If Ingrid or OASIS is going to be used try moving mechanisms from Ingrid, OASIS pages. Some (enlarger or imager wheels on OASIS) might require more than one attempt. In case of persisting problem contact an AO specialist or a Software specialist.
  
  
  

  

  oasisgui INGRID page

   

  

  oasisgui OASIS Engineering page

   

   

 

From AODISPLAY left screen:

• If TopGui has not been left running, type restart or NaomiRestart then topgui & .
• The left half of Topgui is static, the right page gives access to SDSU control, C40, Mirror Control, Light Path, etc either from the icons or from the Tools menu
  

  
  

  

  

  TopGui icons and Tools menu

• From the C40 page  check if all 16 processors are in green. Left ring is for WFS, right for Strain Gauges (ie DM control). The SG icon is pink which means the loop is open, that’s normal.  NaomiRestart usually clears most processor problems, otherwise call an AO specialist.

• In C40 Control under WFS click on Start to get WFS into framing mode and in the Display Control click on Continuous 
• Check noise level on the WFS, either visually (with Max level in the Display Control set at 100, no diamond structure is visible on the image) or more precisely from the WFS Display page, with a Grab, Save as Fits and then display of the file on iraf, using imexam. An rms value of 7 to 10 is normal.
  
  
  
  

  WFS Display page, from which to Grab an image of the WFS

        Back on AODISPLAY

• Check on TopGui if the SG (Strain Gauge) gain is 0.8, otherwise type SG SetGain 0.8

• From the Light Path page load the latest DM flat (usually from last night). On the Fisba monitor with the interferogram, the DM segments will still show lots of fringes.

  

  TopGui Light Path page
  
  

• From TopGui Light Path page open (if not already ticked) the WFS Shutter.
• Send the pick-off probe to 0,0. Spots should be visible on the WFS Display.  Centre approximately the spots on the DM grid (a segment is 2arcsec wide) by entering values in the Pickoff X and Y boxes and clicking Apply, then click on Autocentre from the General Scripts gui to recentre precisely. 

  

  

  General Scripts gui, for AutoCentre, and result of the AutoCentre. To close that pop-up window, just locate the mouse cursor in it and press Enter

   

• If the pick-off probe doesn't move (and status turns to Error) you will need to initialise it:
  from TopGui’s EngGuis – Mechanisms DM bring up 3 cascaded windows: NAOMI Mechanism control mechs.dl, right-click on NAOMI systems to start Wavefront Sensor wfs.dl, right-click on WFS Components to start Pickoff Mechanisms pickoff.dl. Click Init, Start, wait for the Idle status, and click Index, Start. It takes a few minutes to initialise, and this will leave the pick-off probe at (X,Y) = (5.32,3.31). From TopGui send it back to 0, 0.

  

  

  

  

  How to intialise the Pickoff and related mechanisms from the engineering gui's
  
  
  

  
  
  Back to Summary

Checking the image quality on the Simplex Camera AG7

• Display the .fits file with Iraf, use imexam j and k commands, or r for the radial profile. At this stage if the image looks good enough, fwhm of the order of 3 pixels, no further flattening of the DM is needed. Otherwise refer to the complete procedure for mirror flattening.

  

  Example of a good image profile

   

  Checking light reaches OASIS (only if it will be used on the following night)
  
  

• From oasisgui USP page fix the bench (it takes a few minutes for the air to flow away). Simplex light ON, set the iris to -150, use 50/50 dichroic. Then take the Simplex flat OUT, OASIS flat IN; Filter focus to imaging.

• From oasisgui OBSTOOL page, in Set Demand select  Observing mode Imaging, with any filter as Spectral config, for example MR516. Then in Configure tick Oasis and click on Configure Selected Items.

• The instrument mechanisms can also be configured one by one from OASIS (Eng) page, it only takes longer and there's a risk of forgetting something. You should check though that you end up with something like this:

• From Taurus set the standard CCD window: window oasis 1 “[1:2059, 1035:3140]” then take an image: glance oasis 1 and display the file s1.fit with iraf, the spot should be visible.
   

  Checking light reaches INGRID (only if it will be used on the following night)
  
  

• From oasisgui USP page fix the bench, move OASIS flat OUT of the beam. Use IR dichroic. Simplex light ON, Iris to -150.

• From oasisgui INGRID page, configure Ingrid, for example   choose Simplex H and take the pupil imager OUT.

• From Taurus take an image: glance ingrid 1 and display s1.fit with iraf (use ingridql package instead of the basic ing package and display with the idisp command), the spot should be visible.

   

At this point, the basic daily checks can be considered as done.  It's not generally required to the DE to flatten the mirror (DM), unless its figure is really bad. In this case see the Laser Flattening process, in the complete Naomi Readiness Checks.

You can also refer to the Naomi Setup and Observing Recipes page, which is more oriented towards AO support astronomers, and is maintained by Chris Benn.  

Link to Naomi Engineering page

Link to Naomi Astronomy page 

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Last Updated: 2007 Jan 30 Olivier Martin  olivier@ing.iac.es