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Image Quality of SOFI
Updated :
January 2004  -  Malvina Billeres
October 2001 -  Malvina Billeres

1- The Observations you need

For SOFI you can use the template Image_Quality_SOFI.obx (click on the link to retreive it if you need).
You will have 36 positions on the detector (36 fits files).

If you prefer you always can do manually the offset to have the 36 positions on the detector. The main advantage of this method is that you won't have any problem of elongation due to the telescope motion. You can pick the offset values in the template above. 

2- The programs you need

All SOFI scripts and plot programs are ready:

- imagequality.cl : a iraf script to reduce your data;

- image_quality_3.0.py : a python script that processes the data;

- plot_mac.f : a fortan program with smongo inserts to plot the results;

3- The reduction of the data

The iraf script named imagequality.cl  simply substracts the median sky and divides by flat. (so you need flats !!!). The script needs as input a list of the raw data (liste*.lis), some flats and it asks to you the prefix you want to give to the reduced files (ex: LF_J). The final files must be called LF_J_001.fits to LF_J_036.fits. You have to run it inside iraf, of course.....

4- The determination of the image quality

Now you have to use the python program imagequal_3.0.py to extract the star, calculate the ellipticity and plot some graphs. imagequal_3.0.py needs as input:
./SOFI_first_try/DATA/Small_Field/images_reduites/ liste_J.txt SMALL small_J
./SOFI_first_try/DATA/Large_Field_FE/images_reduites/ liste_FE.txt LARGE FE

First column: directory where the reduced images are
Second column: name of the list of all the fits files
Third column: instrument/configuration : SUSI - EMMI - LARGE - SMALL - FE _ SO (the last 4 choices are for SOFI)
Fourth column: the prefix for the final files <prefix>

be sure that the path for the librairies correspond to what you have on your computer.

At the end you have a <prefix>.dat file and <prefix>.ps file.

To start the python program, just enter %> python imagequal_3.0.py



Send comments to: NTT Webmasters <nttweb@eso.org>
Last Update: January , 2004 (Billeres Malvina)