ON-line INT help Information

INT-WFC Quick Notes

STARTING UP OBSERVING SYSTEM
TELESCOPE OBJECT CATALOGUES
DRIVING TELESCOPE FROM CLI
UPDATING FILTER DATABASE
SNAFU PROCEDURE
TEL FOCUS PROCEDURE
GUIDE STAR SELECTION CATALOGUE PROGRAM
OBSERVING LOG
USING GANTRY TERMINAL
SOME USEFUL CLI COMMANDS
CURRENT PROPERTIES OF MOSAIC CCDS
PHYSICAL LAYOUT OF MOSAIC
USEFUL IRAF COMMANDS

STARTING UP OBSERVING SYSTEM

Normal startup LPSS12

logon as observer with the usual password
in "pink" xterm window type
```
	>obssys          - defines aliases etc...
	>startobssys     - fires up observing system
```
[this involves the following sequence of commands which should all be called automatically from the startup script
```
	>talker -n TALKER-SYS &
	>sccd /dev/term/b005 MOSAIC &
	>mcad &
	>dasp INT 1 &
	>tcs &
	>wfcgui-go &      
```
Occassionally the gui interface self destructs on startup and if this happens typing >wfcgui-go & will cure the problem.]
A series of windows will spontaneously appear including:
- the talker log - gives updated diagnostics of what is going on and useful to keep visible to check on system status,
- the observing log - the observing sequence log can be safely minimised,
- the MOSAIC gui interface - where if you cannot type but can drive a mouse you can run the observing system from.
- the original pink xterm window is the CLI (command line interface) alternative to the gui but also has enabled a large number of extra commands.
- NB. If for some reason LPSS15 needs restarting in middle of observing the command
```
 ">dasload lpss15" 
```
  typed in the pink xterm window will reconnect the DAS system to it.

Startup on TOG X-terminal

Open an x-window session on lpss12 using NCD
logon as observer with the usual password

in xterm window type

	>source .login
	>obssys          - defines aliases etc...
	>startobssys     - fires up observing system 
			   and starts autoguider display

	>shutdownobssys  - finish off session cleanly

Press "pause" key to bring up menu and then open serial connection for usual TCS control window.

TELESCOPE OBJECT CATALOGUES

The catalogues for driving the telescope from the DAS are stored in the directory $OBSSYS/etc.
- There is a grid of bright pointing standards in ptgrid.cat
- the active telescope catalogue is stored in tcs.cat

To view and manipulate the catalogue use the normal unix tools eg. "more", "cat", "emacs" or if you want to add objects to it without using an editor at the xterm CLI type

	>object name ra dec equinox    - 
	>add
	>gocat name                    - to move telescope to object

eg.  	>object JQ1 14 05 13.4 -13 0 5 J2000
	>add
	>gocat name

DRIVING TELESCOPE FROM CLI

Some examples of useful TCS commands:

>cmd TCS AUTOGUIDE ON x y   - guide on at position x,y on autoguider CCD
                              default is to specify x y = -1 -1 which
                              cause A/G to guide on current guide star location
>cmd TCS AUTOGUIDE OFF      - turn guiding off

>focus 45.5                 - set telescope focus

>rotate sky 180             - move PF rotator to 180 degrees [default]

>gocat 12+30                - go to pointing grid star assuming ptgrid.cat
                              is part of the user catalogue in 
                              $OBSSYS/etc/tcs.cat

>focusrun arg1 arg2 arg3 arg4 arg5    - procedure for doing a focus run

The arguments are:
                      arg1   - no. of images to take
                      arg2   - separation of images in arcsec N-S direction
                      arg3   - focinc, ie. focus increment (0.1 average seeing
                               0.05 good seeing)
                      arg4   - focus start position (tube temperature 4 deg
                               current best focus with R filter is 45.5)
                      arg5   - integration time (best if >= 5s)

The last image is double spaced.  After deciding on best focus use TCS
focus command (as above) to set telescope focus.

UPDATING FILTER DATABASE

[The filters are currently stored in a special WFC filter box together with spare filter spacers.]

At xterm CLI interface type:

>wfcmdb                     - enable access to WFC filter database (eg. set
                              telescope focus offsets)

The filters are identified by several methods.
- A WFC filter holder number written on each one for ease of identifying when changing filters - this number has no other significance.
- An ING site-wide database number not directly used by the WFC software but stored in the WFC filter database.
- A unique 5 bit code on each filter holder - see below.
- A name translation of the 5 bit code eg. R, U etc...
- A filter position number on the filter wheel eg. 1,2.....6
If simply altering a known filter offset follow the interactive gui and "commit" the changes to the database and "save" on exit.

After exiting from gui type

>cmd MCA RESET              - to update the volatile use of the database
                              and enable the changes.

If changing a filter to another known filter see the section on use of GANTRY terminal.

To install a new filter (in a unique filter holder) you have to "read" the filter holder 5 bit code on the edge of the filter holder.

                       __________________________
         inside edge  |   Bits 0  through  5     |  outside edge
                       --------------------------

where a set bit is a raised part of metal and the least significant bit
is to the left.

For example: the OIII filter has code 1 0 1 1 0 = 13
Update the WFC database using the >wfcmdb and >cmd MCA RESET commands.

SNAFU PROCEDURE

Go to bright star at nominal centre: eg. use pointing grid catalogue command eg. "gocat 12+30" in xterm session on DAS system, or use TCS to go to suitable target.
Either beamswitch A to place star on science device #3 and take exposure with say 4x4 binning to determine position of star. Compute offsets in arcsec to place star on centre of active area eg. pixel coordinates 256,259 for 4x4 binning - each pixel is 4x0.37 arcsec - but do nothing yet.
Or beamswitch B to place star on default autoguider window. Use autoguider 'field' command to take exposure. Compute offsets in arcsec to place star on pixel coordinates 1032,850 (for 1x1 binning - each pixel is 0.37 arcsec) but as above do nothing else yet.
Define suitable HA/INC on TCS put in 'INC' mode and then do 'SNAFU' using handset to move star by computed amount as above. [If rotator at 180 degrees default science display (eg. SAOIMAGE) has N at top and E to left, whilst autoguider has S at top and E to left.]
Check moved correct amount by taking another exposure on either science device or autoguider. If ok press 'ACK' and you are done if not move some more and repeat check.
An extra test for correct rotator centre position is to use beamswitch A to put star on middle of device #3 and then use command "rotate sky 360" in DAS xterm window to move rotator through 180 degrees. Take exposure on #3 again with 4x4 binning and check star is close to centre of chip.

TELESCOPE FOCUS PROCEDURE

take a focus image with the focusrun command.

this gives an image on the CCD's


                -----------------------------
                |                           |
                |                           |
                |                           |
                |       * 1st foc           |
                |       *                   |
                |       *                   |
                |       *                   |
                |                           |
                |       * last foc          |
                |                           |
                |                           |
                -----------------------------

Then to analyse use iraf task - starfocus (nmisc)

 
lpar starfoc
       images = "r47649"        List of images
       (focus = "45.3")         Focus values	(start focus value)
       (fstep = ".1")           Focus step
  (nexposures = "7")            Number of exposures
        (step = "40")           Step in pixels	(for 15 arcsec step)
   (direction = "-line")        Step direction
         (gap = "end")          Double step gap
      (coords = "mark1")        Object coordinates
     (display = yes)            Display images?
       (frame = 1)              Display frame to use
       (level = 0.5)            Measurement level (fraction or percent)
        (size = "FWHM")         Size to display
        (beta = INDEF)          Moffat beta parameter
       (scale = 0.375)          Pixel scale	(for loral ccds)
      (radius = 15.)            Measurement radius (pixels)
     (sbuffer = 2.)             Sky buffer (pixels)
      (swidth = 2.)             Sky width (pixels)
  (saturation = 65536.)         Saturation level
  (ignore_sat = no)             Ignore objects with saturated pixels?
  (iterations = 2)              Number of radius adjustment iterations
     (xcenter = INDEF)          X field center (pixels)
     (ycenter = INDEF)          Y field center (pixels)
     (logfile = "logfile")      Logfile
    (imagecur = "")             Image cursor input
    (graphcur = "")             Graphics cursor input
        (mode = "ql")

The above is an example of parameters needed ...
When the picture comes up hit g or m on the top of each star sequence in the image - q at the end and it gives the best focus position

GUIDE STAR SELECTION CATALOGUE PROGRAM

The HST guide star catalogue to V of approximately 15th magnitude is stored on /soft/cats/hstguide.sun . This 300 Mbyte file contains the complete GSC catalogue and can be efficiently searched for guide stars for the WFC.

To run the software the following environment variables and alias have to be set up in an observing system (currently LPSS12) xterm window:

>setenv GSC_DATA /soft/cats/hstguide.sun   - pointer to the HST catalogue file
>setenv PGPLOT_FONT /star/etc/grfont.dat   - an interim bodge 
>alias gsc_apm '/home/mike/soft/apm/gsc_apm'

The program can either be invoked using command line options such as:

>gsc_apm RaDec="10 30 0 -1 0 0" Rotpos=180 Equinox=J2000
>gsc_apm Rotpos=90 Equinox=B1950 RaDec="21 30 11.3 12 10"

or run interactively viz:
```
>gsc_apm
```
Command lines arguments are:
- RaDec="hh mm ss dd mm ss"
- RotPos=angle (180 default)
- Equinox=J2000 (or B1950)

Example command lines:

	>gsc_apm RaDec="10 30 0 -1 0 0" Rotpos=180 Equinox=J2000
	>gsc_apm Rotpos=90 Equinox=B1950 RaDec="21 30 11.3 12 10"

Ok...... do it interactively then.......

  Rotator angle [180?]
  Do you want to impose magnitude cut ? [N] 
  Do you want to precess input coordinates to J2000 ? [N]
  Field Centre:(h,m,s,d,m,s) 12 0 0 0 0 0
  File: gsc.out already exists - clobber ? [Y]
  Catalogue Ra limits =  8963072  9001638
  Possible guide stars (also listed in gsc.out)
  
 Catalogue no.     Ra           Dec       Magn  Guide X  Guide Y
 
  49320270   11 59 44.965  - 0 25 11.57   13.6  1512.7    20.1
  49320404   11 59 48.562  - 0 21 11.56   14.6  1367.0   668.0
  49320532   11 59 56.012  - 0 19 22.73   15.2  1065.4   961.7
  49390619   12  0  0.230  - 0 19 21.36   12.6   894.7   965.4
  49390146   12  0 18.344  - 0 23 41.42   15.2   161.2   263.4
  
 Total no. catalogue stars read in =  161
  
  Do you want plot E-W direction reversed ? [N]
  Do you want to alter default line width ? [N]
  Graphics device/type (? to see list, default /NULL): 
  Do you want another plot ? [N]

The catalogue information is also written to gsc.out in the current directory. A plot of a 1x1 degree field with the layout of the science and autoguider CCDs superposed is optionally available.

OBSERVING LOG

The observing log is actually stored in /ing/etc and called something like 19970525.INT . For printing out your own version copy to a suitable directory, edit out any crap and put in any comments and then use
```
	>a2ps -1 19970525.MINE > 199702525.ps
```
if you want a readable printed copy.

USING GANTRY TERMINAL

For changing filters or rotating top end for cryostat fill, which should be done at rotator position of 180 or testing shutter etc..
Check RS232 cable is connected to top socket on gantry rail.
If console does not respond check communication is set for 8 bits no parity by pressing "PF3" and then using cursor keys to select COMMS option and "enter key to scroll through options for 8 bit no parity. After setting COMMS press "PF3" to go back to terminal mode.
Hit a couple of times to get DAS system login prompt.
Login as observer, using standard password.

Type

	> obssys                - sets up aliases etc..
	[menu]                  - select item 8 ie. WFC option
	> startobssys

To change a particular filter
```
	GANTRY> change R        - filter name or number, eg. R, 3
```
- wait for action to prompt.....
- turn the black knurled knob on filter access hatch to open it....
- remove filter and change for new one....
- turn black kbob back to close the hatch which is then locked automatically

To rotate PF top-end

GANTRY> rotate sky 180  - rotate PF top end to 180 degrees

To test shutter

GANTRY> wfcshutter open
GANTRY> wfcshutter close

Logout when finished
```
GANTRY> logout
```

SOME USEFUL CLI COMMANDS

The MOSAIC gui is intuitively obvious even for astronomers. However, for direct TCS control including autoguider on/off and other diagnostic commands the CLI interface is needed.
DITS (Distributed Instrument Tasking System) task command takes the generic form:
```
	>cmd [options] D-task [action arguments]
```

Some useful options are:

	-g  which gets information about D-task
	 -o  obey action [default]

eg.	>cmd -g TCS POSITION      -  get information about telescope

To reboot CCD controller:
```
>cmd MOSAIC SCCD-INIT MOS1
```

To run observing system from CLI

>filter R                  - change to R filter
>run exp-time ["title"]    - do a science run
>bias                      - take a bias frame
>glance                    - glance frame
>abort                     - terminates active run without saving data
                             [do not use if CCDs are reading out]
>finish                    - terminate exposure and readout

>dasreset                  - restarts data aquisition subsystem after fu's
>cleanup                   - clear up after system hang up before restarting

CURRENT PROPERTIES OF MOSAIC CCDS

Turbo is the recommended readout speed = total readout time of 130s for all 4 science devices.

At turbo the gain and readout noise for the active devices are:

        CCD      Gain e-/ADU     Readout noise e-     Full Well e-

        #2           1.6               14              80,000+
        #3           1.45              13              80,000+
        #4           1.4               17              60,000

The CCD broadband zero-points (ie. that magnitude that gives 1 photon/s) are:

        CCD        U      B      V      R      I      Z

        #2       23.9    25.3   25.5   25.5   25.0
        #3       21.5    24.6   25.2   25.3   24.8
        #4       23.8    25.5   25.5   25.5   25.0

(c.f. predicted) 24.0    25.0   25.0   24.5   24.0

#2  Has vertical streaking in bias frames
#3  Currently has sensitivity problem and non-uniform response
#4  Charge injection problem limit full well to 60,000 e-

U throughputs measured 11/06/97, BVRI measured 25/05/97

PHYSICAL LAYOUT OF MOSAIC

CCD Layout and orientation for rotator at 180 deg:

                           N

           --------------     --------------
          |              |   |              |
          |              |   |              |
          |              |   |              |
          |      #3      |   |      #2      |
          |              |   |              |
          |     W8-1     |   |    W12-1.1   |
          |              |   |              |
           --------------     --------------

      E                    x
           --------------     --------------
          |              |   |              |
          |              |   |              |
          |              | o |              |
          |      #4      |   |       #1     |
          |              |   |              |
          |    W5-1.1    |   |    W16-1.1   |
          |              |   |              |
           --------------     --------------


                    -------------
                   |             |                   
                   |      #5     |                   
                   |    W10-4    |                   
                   |.............|                   
                   | Masked for  |                   
                   |   frame     |                   
                   |  transfer   |                   
                    -------------

Active area 2048x2048 pixels, overscan regions give 2076x2076 pixels on readout.
Nominal 15 micron pixels (needs astrometric check) gives active area of 30.72x30.72mm or 12.6x12.6 arcmin per CCD.
NB. The rotator centre (o) is offset from the nominal mosaic centre (x).
- #1 Dead device.
- #2 Charge transfer problems but otherwise ok.
  - Trimsec [13:2060,29:2076]
  - Biassec [1:2076,1;28]
- #3 Sensitivity problem causes apparent vignetting otherwise ok.
  - Trimsec [1:2048,13:2060]
  - Biassec [2049:2076,1:2076]
- #4 Wafer mask 'tram lines' visible otherwsie ok.
  - Trimsec [17:2064,1:2048]
  - Biassec [1:2076,2049:2076]
- #5 Autoguider CCD with outer half masked for frame transfer.
Note that flip/rotation of CCD pixel array is applied at readout to give correct orientation on sky - necessary because of symmetric corner readout of devices.

Capstan settings viewed with rotator at 180 deg

                                 Dome

                 ----------------------------------------
                |                                        |
                |                                        |
                |     8.93mm                             |
                |                                        |
                |                                        |
                |                                        |
                |                                        |
                |                                        |
                |                                        |
                |                             7.43mm     |
                |                                        |
                |                                        |
                |                                        |
                |                                        |
                |                                        |
                |                                        |
                |     7.45mm                             |
                |                                        |
                |                                        |
                -----------------------------------------

                                 Floor

Astrometry of CCD layout relative to rotator centre.


                     ^
                     |
                     y
Using a conventional  x --->  coordinate system in the 180 rotator orientation 
illustrated above and defining the rotator centre as the origin:

The nominal centre of mosaic is defined to be at (0",281") or (0mm,11.38mm) from rotator centre.
- #1 Unknown
- #2 Centre of active area is at (449",717") or (18.17mm,29.01mm)
- #3 Centre of active area is at (-398",710") or (-16.10mm,28.74mm)
- #4 Centre of active area is at (-398",-148") or (-16.11mm,-5.99mm)
- #5 Offset to default size frame window
  - (400,288) centred at (1032,850)
  - (56",-1210") or (2.3mm,-49.0mm)

This gives TCS aperture offsets of:

Nominal to rotator centre	AOXNOM = -1.3623D-3 (radians)
Aperture A ie. nominal to centre of #3	TDATA(11) = -429 (arcsec)
	TDATA(12) = 398 (arcsec)
Aperture B ie. nominal to autoguider	TDATA(13) = 1210 (arcsec)
central default window (1032,850)	TDATA(14) = -56 (arcsec)

Pointing model constants from 23/5/97 automatic pointing test
- PCIH = -1.61615D-3
- PCID = -3.46446D-3
- PCCH = 5.81470D-4
using Perkin Elmer nomenclature.

USEFUL IRAF COMMANDS

wfc_mosaic will create an image of the presently three working CCD's with the correct spacing (images block averaged by afactor of 2*2). This assumes that iraf has been run up from the home directory of intguest.

This page last updated: 12 June 1997

Mike Irwin ( mike@ast.cam.ac.uk ) (RGO WFC Project Scientist)
Nic Walton (naw@ing.iac.es ) (INT Telescope Manager)