Notes Page:


October 1998
Nov/Dec 1998
March 1999

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MPE-3D Special Notes for Specific Runs:

October 1998

On this run the halogen lamps which we used for the dome flatfields had very different spectral characteristics than those used in previous (AAT) runs. They were not as spectrally smooth as former lamps, rendering them unusable for the spectral component of the (at least) K-band flatfield. Fear not! This simply means that to generate proper flatfields for this run you must do it the "old-fashioned" way.

What this means is that you will use the dome exposures for the spatial component of the flatfield and the incandescent bulb exposures for the spectral component. The only difficulty in doing this lies on my side. That is, since in this case each of the individual 256 x 256 must be individually wavelength calibrated, I had to generate the appropriate calibration values for these images as well as the merged ones. I have done so for the case of the K-band values, but have not yet determined the necessity of doing it for the H-band (I think it is not an issue). So, without further ado, here is a sample COLA script (red_flat_os.col) for generating appropriate flatfields:
 

!Dome lamp on; piezo 1
"3dlin inset=flatk0401 ext=gs nsub=6 seq=3 piez=1 limit=30000        dark=dark_25s.gsa darks=1 del=y okay=y"
!Dome lamp on; piezo 2
"3dlin inset=flatk0402 ext=gs nsub=6 seq=3 piez=2 limit=30000        dark=dark_25s.gsa darks=1 del=y okay=y"
!Dome lamp off; piezo 2
"3dlin inset=flatk0403 ext=gs nsub=6 seq=3 piez=2 limit=30000        dark=dark_25s.gsa darks=1 del=y okay=y"
!Dome lamp off; piezo 1
"3dlin inset=flatk0404 ext=gs nsub=6 seq=3 piez=1 limit=30000        dark=dark_25s.gsa darks=1 del=y okay=y"

"sub inset=flatk0401p1.gsaw 1 box= setx=flatk0404p1.gsaw 1 boxx=      outset=spatkn1.gsawy 1 okay=y"
"sub inset=flatk0402p2.gsaw 1 box= setx=flatk0403p2.gsaw 1 boxx=      outset=spatkn2.gsawy 1 okay=y"

!Bulb on; piezo 1
"3dlin inset=bulbk1101 ext=gs nsub=6 seq=3 piez=1 limit=30000        dark=dark_4s.gsa darks=1 del=y okay=y"
!Bulb on; piezo 2
"3dlin inset=bulbk1102 ext=gs nsub=6 seq=3 piez=2 limit=30000        dark=dark_4s.gsa darks=1 del=y okay=y"
!Bulb off; piezo 2
"3dlin inset=bulbk1103 ext=gs nsub=6 seq=3 piez=2 limit=30000        dark=dark_4s.gsa darks=1 del=y okay=y"
!Bulb off; piezo 1
"3dlin inset=bulbk1104 ext=gs nsub=6 seq=3 piez=1 limit=30000        dark=dark_4s.gsa darks=1 del=y okay=y"

"sub inset=bulbk1101p1.gsaw 1 box= setx=bulbk1104p1.gsaw 1 boxx=      outset=speckn1.gsawy 1 okay=y"
"sub inset=bulbk1102p2.gsaw 1 box= setx=bulbk1103p2.gsaw 1 boxx=      outset=speckn2.gsawy 1 okay=y"

"3dmkflat spat=spatkn1.gsawy spec=speckn1.gsawy           calset=calkn_041098_os flat=osflat1"
"3dmkflat spat=spatkn2.gsawy spec=speckn2.gsawy           calset=calkn_041098_os2 flat=osflat2"

The calsets in the above script were made with this script (red_cal_os.col):
 
!Spectral calibration files
!Lamp on; piezo 1
"3dcmean inset=neon0401.gs start=2 end=21 outset=neon0401.gsa sub=1         del=y okay=y"
!Lamp off; piezo 1
"3dcmean inset=neon0404.gs start=2 end=21 outset=neon0404.gsa sub=1         del=y okay=y"

"sub inset=neon0401.gsa 1 box= setx=neon0404.gsa 1 boxx=
     outset=neon0401.gsay 1 okay=y"

!Creating the wavelength calibration frame
"megacal3d inset=neon0401.gsay 1 run=a984 band=k
           outset=calkn_041098_os 1 okay=y"

!Spectral calibration files
!Lamp on; piezo 2
"3dcmean inset=neon0402.gs start=2 end=21 outset=neon0402.gsa sub=1         del=y okay=y"
!Lamp off; piezo 2
"3dcmean inset=neon0403.gs start=2 end=21 outset=neon0403.gsa sub=1         del=y okay=y"

"sub inset=neon0402.gsa 1 box= setx=neon0403.gsa 1 boxx=
     outset=neon0402.gsay 1 okay=y"

!Creating the wavelength calibration frame
"megacal3d inset=neon0402.gsay 1 run=a984a band=k
           outset=calkn_041098_os2 1 okay=y"
 

Finally, here is a "shopping list" of stuff that you'll need (and probably don't have already) to be able to generate (K-band) flatfields for this run:

  1. 3dmkflat.col
  2. megacal3d.c
  3. incandescent bulb exposures (no longer available online)

November/December 1998

As the dark exposures for this run were taken on the final morning, they were not available at the time when a number of observers wrote their data to tape. Since the run, I have "post-pre-processed" all the dark files (that is, I've already run the ".gs" files through 3dcmean to produce cleaned average frames). These files are available in the Darks-NovDec-1998 directory. For each dark exposure there is a gzip'd tar file of gzip'd ".descr" and ".image" files. For example, the file dark_15s.tar.gz contains the files for the 15 second dark exposures. To extract them from that file follow these steps:
  1. Download dark_15s.tar.gz
  2. gunzip dark_15s.tar.gz
  3. tar xvf dark_15s.tar
  4. gunzip dark_15s.*
What you will have at that point are two files: dark_15s.gsa.descr and dark_15s.gsa.image. The subset containing the data is number 1, such that the correct usage in 3dlin is dark=dark_15s.gsa darks=1.NOTE: these exposures are no longer available online.
 

March 1999 


On this run 3D's internal piezo-driven mirror which is used for full spectral sampling failed.  The result was that we observed withoput attempting to drive this mirror, while observing with our usual sequence (noted as LPSKY in the piezo column of the logbook).  This is summarized in the Table below:
 

Piezo Setting
Frame Position Normal Operation March 1999
1 source 1 off
2 sky 1 off
3 source 1 off
4 source 2 off
5 sky 2 off
repeating the last 4 rows n times, such that the total number of frames is 4n+1
"LPSKY" Operational Mode

 So, a few changes had to be made to the software to accomodate data taken in this fashion.  The modified code includes  3dlin.col, 3dcenter2000.col, 3dstar2.col, 3dcubin.c, 3drebin1.cNOTE: Also be sure to check the Data Reduction page for non-piezo-related updates to other routines.

 In the case of 3dlin.col, the change involved introducing the concept of using a value of 0 for the Keyword PIEZ.  This value is recognized when using values of 3, 33, 5, and 55 for the Keyword SEQU.  In those cases the result is a series of on-off pairs which are sequentially numbered, without the "customary" p1 or p2 appearing.  See the top of the script itself for details.

In the cases of 3dcenter2000.col and 3dstar2.col the changes involved introducing an automatic means of  determining whether the data were taken in the normal fashion, or taken without the aide of 3D's piezo.  In the latter case simply enter the same name for the Keywords SET and SETP.  See the tops of the scripts themselves for details.  Further, if you have data taken without the aide of 3D's piezo the wavelength calibration is done within these scripts using starcal2 rather than  3dcal (so be sure to get a copy in the usual place).  Finally, I took this opportunity to make fundamental changes to 3dstar2.col such that it more resembles the structure and function of 3dcenter2000.col (by adding the Keywords TWEAK and DPCOR).

In the cases of 3dcubin.c and 3drebin1.c the changes involved enable the routines to operate normally on either 256 x 600 (normal, piezo subsampled) data or 256 x 300 (no piezo) data.  In each case the routines autosense which kind of data is being input and act accordingly.  In addition, as always there is a new  input file (3dcubin.991k) for use in reducing K-band data from March 1999.

                           This page was last modified on 06April 1999.


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