The INGRID user's guide

1. Starting the system
2. INGRID real time display (RTD)
3. INGRID mechanisms
4. INGRID observing commands
   • INGRID data acquisition commands
   • INGRID diagnostic commands
   • TCS commands
5. End of night
6. Shutting down the system
7. Writing data tapes
8. Important notes

1. Starting the system

• Log on to the Sun workstation taurus (next to the ICL computer):
  
  • LOGIN: whtobs
    PASSWORD: provided by your support astronomer
  An openwindows session starts, and an xterm pink window (labeled "Central intelligence of observing system") and several xterm orange windows will appear. Also a netscape window appears, which shows the UltraDas Software Operations Manual (command dictionary included).
  Minimize all the orange windows except the one corresponding to the DAS (data adquisition system) computer which controls INGRID (get its name from the white board above the ICL computer). It is entitled whtdas11 at the moment (July 2003).

• Start the data adquisition system:
  • Type obssys in the whtdas11 (orange) window. It defines the software to use and will then prompt you to select the observing system. Type the option number corresponding to INGRID (option 1 for INGRID + NAOMI at the moment (July 2003) or select the "manual camera selection") and wait until the prompt DAS> appears.
  • Type DAS>startobssys to start the software. Wait until the prompt is back and minimize this window (it is not needed until you shut down the system).

• Start the system computer:
  • Type obssys in the pink window.
  • Enter the same option number as in the orange DAS window and wait to get the prompt SYS>.
  • Type SYS>startobssys
    This initializes the telescope control software (TCS) link, the INGRID mechanism controller and the INGRID SDSU controller, and brings up several new windows:
    • A real time display (RTD) control tool
      
    • An Ximtool to display the data
      
    • The INGRID mechanism mimic.
      To get more detailed information about the INGRID mechanism wheels, select Control from the File menu.
      
    • An "identify" window.
      Enter your name and proposal identification.
      
    • The observing log.
      The log is automatically updated each time a new file is written to disk. To put comments on a file click once with the mouse on the file and a box appears where you can type shorts comments.
      
    • The array info display window
      
    • The "talker" window. It displays messages from the observing system to the user.

• SYS>fwheel1 ingrid datum;fwheel2 ingrid datum;pstop ingrid datum
  Initinialize the pupil stop wheel and the two filter wheels. Check that the motor readback position after datum in all wheels is close to 0.169 (if that is not the case in any wheel, datum it again).

• If you want, you can bring up a telescope info display window. Type:
  SYS>tcsinfo&
  

• Set the array readout speed to slow:
  SYS>rspeed ingrid slow
  The fast speed readout is not available at the moment (Aug 2002).

• To examine INGRID data:
  
  • Log on to lpss13, the sparc station dedicated to INGRID quick look reduction (two monitors on the right of taurus):
    LOGIN: whtguest
    PASSWORD: provided by your support astronomer.
  • Open up an xgterm (type xgterm -sb&).
  • Open up an Ximtool (type ximtool&).
  • Start an IRAF session (type cl or ncl) from the home directory (/home/whtguest), in the recently opened xgterm.
  • Change to the disk and directory where the data is going to be stored ( e.g. cl>cd /obsdata/whtb/20020824).
  • Type: cl>ingrid in IRAF, to start up the INGRID quick look reduction package.

• Now is a good moment to take two darks of the same exposure time and measure the INGRID array readout noise:
  • SYS>filter ingrid blank Put blanks in the light path.
  • SYS>dark ingrid 2 "dark 2s a" Take the first dark frame.
  • SYS>dark ingrid 2 "dark 2s b" Take the second dark frame.
  • On lpss13, within the ingrid quick look package, type: in>ifindron and enter the filename of the two darks. The result is given in ADU.

  IMPORTANT: the readout noise value given in the image FITS headers is fixed, and regularly updated, but not derived from each specific image. Observers are therefore recommended to check the readout noise of their images.

2. INGRID real time display (RTD)

The INGRID real time display (RTD) consists of two elements: a RTD control panel and an Ximtool to display the data.

RTD control panel. INGRID fits data files contain two extensions (e.g. r414230.fit[*,*,1] and r414230.fit[*,*,2]) which correspond to the array readout after the reset process and before the integration (the pre-read, extension 1) and the readout of the array after integration has finished (the post-read or post-integration data set with extension 2). Click here for a more detailed explanation.

The RTD control panel (image below) includes several options which allow the user to display either the post-read or the pre-read image extensions or the post-pre (=post minus pre) image of a certain observation data. Also, it is possible to display the result of subtracting one image from another (e.g. a sky subtracted image). This operation affects only the displayed data (i.e. only raw data is stored on disk).

On the RTD control tool window, from top to bottom:

• Observation data Shows the file name of the image actually displayed on the Ximtool.
• Reference data Shows the file name of the image loaded as reference data (see below).
• Status Status of the RTD. It can be ``scanning'' if the Data detection is selected to be on (clicking on the corresponding diamond), or ``data detection off'' if Data detection is off.
• Data directory Shows the directory where the data is being stored.
• Data detection If you click on the on box, the new images are automatically loaded into the RTD.
• Display state This section offers several options to display the data, which are activated by clicking on the diamonds on the left:
  • OBS-REF Displays the post minus pre of the observation data minus the post minus pre of the reference data
  • OBS/REF pre Displays the pre-read of the observation/reference data
  • OBS/REF post Displays the post-read of the observation/reference data
  • OBS/REF post-pre Displays the post minus pre of the observation/reference data
• Refresh Click on this button to refresh the display on the Ximtool.
• OBS->REF Load the current observation data as reference data.
• Quit Click on this button to quit the RTD.
• Load OBS/REF data These buttons can be used to load any fits files of the Data directory as Observation data/Reference data: type the file name of the image in the corresponding box and click the corresponding button.

3. INGRID mechanisms

INGRID mechanisms comprises a pupil stop wheel, two filter wheels, the focus drive and a pupil imager.
During normal science observations one broad or narrow filter might be in the beam as well as an appropriated pupil stop to eliminate as much unwanted background radiation as possible before entering the camera.

• Status of INGRID mechanisms

  The position of the filter wheels, the pupil stop wheel, the instrument internal focus and the pupil imager can be checked by means of the mechanisms' windows or using a line command:
  

  • The INGRID mechanism mimic summarizes the selected positions of the filter and pupil stop wheels, the pupil imager and the instrument internal focus value in microns.
    A graphical user interface (GUI) can be obtained from the File menu, selecting Control. The selected positions in each wheel are coloured green.
  • In the pink instrument control system window, the status of the INGRID controller and all the mechanisms can be obtained with:
    SYS> mchstat

• Moving INGRID mechanisms

  Mechanisms can be moved using either the GUI or the command line interface (pink window).

  • From the GUI
    • Filters and pupil stops. To move any of the three wheels, enable the GUI (clicking on the right-top square) and then click on the filter/pupil stop you want in the beam. Whilst moving, the whole wheel is coloured blue and the selected position yellow. When the wheel movement has finished the demanded filter turns green (success) or red (undefined position). If the latter occurs, you have to datum the corresponding wheel (click in the datum button or type e.g.: SYS>fwheel1 ingrid datum (or fwheel2, or pstop)). IMPORTANT: the motion of two wheels simultaneously can result in losing wheel accuracy and hence it is not recommended.
      
    • Focus drive. To select an array focus value, type the required focus value in microns in the box and hit return). For INGRID+NAOMI observations, the INGRID internal focus is currently fixed at -1200 microns (August 2002).

  • From the command line in the ``pink window''
    • Filters. Filter wheel movements can be performed with the commands fwheel1 ingrid <filter name> or fwheel2 ingrid <filter name> for broad band and narrow band filters respectively.
      
    • Pupil stops can be changed independently of filter movements with the command:
      SYS>pstop ingrid <option>, where <option> for observations with NAOMI are:
      
      • naomi-obs, osca-obs  Pupil stops with central obscuration, used for observations with NAOMI and OSCA respectively.
      • naomi-clr, osca-clr  Pupil stops without central obscuration, used for observations with NAOMI and OSCA respectively.
      • clear No pupil stop in the beam.
      • blank1  Aluminium blank for dark frames acquisition.
      Consult your support astronomer about most appropriated pupil stop for your observations.
      For details on the dimensions of the pupil stops click here.
    • INGRID focus drive. Type SYS>ifocus ingrid <position in microns>.
    • Pupil imager. Only used in engineering mode. In normal astronomical use the pupil imager position must be out of the light beam. Call your support astronomer or duty engineer to take the pupil imager out if necessary.

4. INGRID observing commands

A complete list and description of the commands can be found in the command dictionary of the UltraDas Software manual (except the dither command for INGRID+NAOMI, which is described below).
A summary of the most commonly used commands is given here for a quick reference:

• INGRID data acquisition commands
  Some of the most important commands related to data acquisition are listed below (arguments are denoted by <>):
  • rmode ingrid mndr < Nr> < N coav>
    Sets the number of MNDR (multiple non-destructive reads) to Nr and the number of coaverages to N coav. Nr is the number of times that the array is read not-destructively prior and after an integration period. The array data from the Nr pre and post-integration reads respectively are averaged independently. Nr is an integer between 1 and 16 (default is 1; i.e. correlated double sampling). N coav is the number of accumulated exposures that are averaged and written as a single output file.

  • coave ingrid < N coav>
    Sets the number of coaverages to N coav.

  • multglance ingrid <N> < int time>
    Produces a sequence of <N> exposures of the required integration time. E.g.: multglance ingrid 999 2 produces a sequence of 999 2s exposures. The sequence can be finished by pressing control-C.

  • run ingrid <int time> <"title">
    Takes a run and saves it in: rxxxxxx.fit.
    E.g. run 8 "FS33 ks", an 8 second exposure and store it in the output file (e.g. r240976.fit).The title of the fits file is set to "FS33 ks". If the number of coaverages has previously been set to 2 (i.e. coave ingrid 2 or rmode ingrid mndr 1 2) the command run 8 "FS33 ks" takes two 8 second exposures in succession, then coaverages the data before storing in the output file (e.g. r240976.fit).

  • dark ingrid <int time> <"title">
    Takes a run and set the OBSTYPE header parameter to DARK (arguments are described below).

  • flat ingrid <int time><"title">
    Takes a run and set the OBSTYPE header parameter to FLAT.

  • glance ingrid <int time>
    Takes an exposure and saves it in s1.fit. This file is overwritten when a new glance is taken.

  • scratch ingrid <k> < int time> <"title">
    Takes a run and saves it in: sk.fit.k is an integer within the range 1-99. The scratch file sk.fit is overwritten when a new scratch<k> is taken.

  • multrun ingrid <m> <int time> <"title">
    Same as run but repeats the run sequence m times and generates m output files.

  • multflat ingrid <m> <int time> <"title">
    Same as flat but repeats the run sequence m times and generates m output files.

  • multdark ingrid <m> <int time> <"title">
    Same as run but repeats the dark sequence m times and generates m output files.

  • dither -intcount <integrations> -secs <int time> -offset <x offset> <y offset> -title <"title"> -5point <x offset> <y offset>
    The dither command takes exposures at different telescope positions while using the AO system NAOMI. The number of pointings of the dither, the exposure time, title and size of the telescope offsets are some of the options of this command.
    E.g.:

    dither -intcount 2 -secs 10 -offset 0 0 -title "fs28 ks" -5point 4 4

    In this case, the command moves the telescope to 5 points with offsets of +4,-4 arcsec from the central position in x and y, takes 2 images of 10 seconds (and number of coaverages previously set) at each position and set the title of the fits file to "fs28 ks". At the beginning of the dither the loop should be closed by the observer or the SA. The script then opens the loop before the telescope moves, moves te telescope and then the WFS "pickoff" mirror to pick up the star again, and close the loop before the following exposure starts. The dither command only works for sky PA = 0.

    A detailed explanation about the dither command and its options is given here.

  The arguments above stand for

     < int time> Integration time in seconds.
     < "title">   Title of the exposure recorded in the image header (optional argument).
     < x offset> Telescope offsets in arcsec.
     < y offset>

• INGRID diagnostic commands
  • detstat   Shows detector status and temperature of the monitoring points.
  • mchstat Shows mechanisms and INGRID controller status

• TCS commands
  • user "ENTER APERTURE <number><ra offset> <dec offset>"
    Defines the aperture < number> characterized by <ra offset> and <dec offset> arcsec offsets in RA and DEC respectively (e.g. user "ENTER APERTURE 1 -400 0")
    
  • aperture <number>
    Offsets the telescope according to the previously defined aperture
    
  • offset arc <ra offset> <dec offset>
    Offsets the telescope by <ra offset> arcsec and <dec offset> arcsec in RA and DEC respectively from the nominal position
    
  • gocat <object_name>
    Moves the telescope to the object <object_name> if this has previously been loaded into the TCS
    
  • object <object_name> <ra(hh mm ss.ss)> <dec(dd mm ss.ss)> <equinox>
    add
    Adds the object <object_name> to the catalog

5. End of night

• At the end of the night, please put blanks into the light path:
  SYS>filter ingrid blank
  

6. Shutting down the system

• Shut down the system computer:

  Type SYS>shutdownobssys on the pink window and wait until the prompt is back. Most of the windows will disappear (the RTD, log, mechanism mimic, array info window, talker,identify window).

• Shut down the DAS:

  Type DAS>shutdownobssys
  on the DAS orange window corresponding to INGRID and wait until the prompt is back.

• Close the TCS display window manually: from the File menu, select Exit
• Close the Ximtool window: from the File menu, select Quit .
• Log out of INGRID's control computer: click the right mouse button on the background screen and select exit.

7. Writing data tapes

• Get a DAT tape from the box located in the terminal area of the WHT, and fill in your initials, date, etc in the folder.
• Put the DAT tape in the DAT drive in lupus (in the terminal area).
• Open up an xgterm.
• cd /obsdata/wht?/yyyymmdd
  
• There are two options:
  • Use the tar command to write the data tape; e.g.
    tar -cvf /dev/rmt/0lbn .
  • or alternatively type:
    fitsinit   and follow the instructions and answer the questions.
    fitsout   and answer the questions again.
    

NOTE: If you write the data tape with fitsinit/fitsout, use the mscrfits command in the mscred IRAF package for reading the data. This is necessary because INGRID images are multi extension images.

8. Important notes

• If the RTD control panel disappears, type the following in the pink window:

  SYS>startrtd&

• Remember to take dark frames of the same exposure time of your science frames. The dark level for the INGRID array can only be approximately be scaled with time. Also, it is dependent on the temperature of the array; therefore the dark level is not stable from night to night.
  • In the iraf session and within the INGRID quick look reduction package, use the task ilistdark to get a list of the exposure times of all your INGRID science frames; e.g.:
    in>ilistdark r*.fit
  • Put blanks into the light path:
  • SYS>filter ingrid blank
  • Take the darks of the exposure times listed by ilistdark using the command dark. E.g.:
    SYS>dark ingrid 10 "dark 10s"

    This takes one dark frame of 10s exposure time and the title of the FITS image is set to "dark 10s". You can generate an observing script to get the dark frames for the exposure lengths needed and then execute it from the command line.