BADPIX masks for SUSI2
on the NTT

Description

This page contains BADPIX masks for SUSI2

A detailed report on the creation of the BADPIX masks can be found here, while the following is a summary of the processes and the resulting BADPIX masks for SUSI2. NOTE: The masks for SUSI2 are NOT trimmed

Program

I have written a PERL script ( mkBADPIX.pl ) which takes the raw data and outputs the tarred, gzipped badpixel files to go on the web.

Creation -- What mkBADPIX.pl does

The BADPIX masks for SUSI2 are created in the following way:

Take: 5 Bias images, 5 Domeflats with low counts (~5000 counts), 5 Domeflats with high counts (~20,000 counts)
Create 2 different BADPIX masks for SUSI2:
1. One where the SUSI MEF files are later split into individual chips. This is useful if you wish to reduce the two SUSI chips individually.
2. One where the SUSI MEF files are first converted into single FITS files with insusi.prg . This is useful if you wish to combine all your data into a single FITS file from the start.
The following is a flow-chart of the script:
While SUSI images are still in MEF format, and using the MSCRED package:
Zerocombine the Bias images
Bias subtract the Domeflat images
Flatcombine the domeflats with high counts - FLATHIGH
Flatcombine the domeflats with low counts - FLATLOW
Divide the flatfield images:
- mscarith FLATLOW.fits / FLATHIGH.fits FLATLHRATIO.fits
To create the 2 separate files for reducing the chips separately
- mscsplit FLATLHRATIO.fits (produces FLATLHRATIO_1.fits, FLATLHRATIO_2.fits)
To create a single FITS file from the MEF SUSI file:
- run insusi.prg (produces FLATLHRATIOsingle.fits)
Create the BADPIX masks using the parameters for ccdmask listed below:
1. ccdmask FLATLHRATIOsingle.fits BADPIX_SUSI_date_binning.pl
2. ccdmask FLATLHRATIO_1.fits BADPIX_SUSI_date_binning_1.pl
  ccdmask FLATLHRATIO_2.fits BADPIX_SUSI_date_binning_2.pl
BADPIX masks are made for both 1x1 and 2x2 binning.
The parameters used in the ccdmask task are the following:


                    Image Reduction and Analysis Facility
PACKAGE = ccdred
   TASK = ccdmask

image   =                       Input image
mask    =                       Output pixel mask
(ncmed  =                    7) Column box size for median level calculation
(nlmed  =                    7) Line box size for median level calculation
(ncsig  =                   15) Column box size for sigma calculation
(nlsig  =                   15) Line box size for sigma calculation
(lsigma =                  20.) Low clipping sigma
(hsigma =                  20.) High clipping sigma
(ngood  =                    5) Minimum column length of good pixel seqments
(linterp=                    2) Mask value for line interpolation 
(cinterp=                    3) Mask value for column interpolation 
(eqinter=                    2) Mask value for equal interpolation
(mode   =                   ql)

BADPIX masks

Date	Single, untrimmed pixel list file created from SUSI2 MEF images merged into a simple FITS file with insusi.prg		2 separate, untrimmed pixel list files for reducing the SUSI2 chips separately
	1x1 binning	2x2 binning	1x1 binning	2x2 binning
24 Oct 2005	BADPIX_SUSI_20051024_1x1.pl	BADPIX_SUSI_20051024_2x2.pl	BADPIX_SUSI_20051024_1x1.tar.gz	BADPIX_SUSI_20051024_2x2.tar.gz
17 Mar 2004	BADPIX_SUSI_20040317_1x1.pl	BADPIX_SUSI_20040317_2x2.pl	BADPIX_SUSI_20040317_1x1.tar.gz	BADPIX_SUSI_20040317_2x2.tar.gz
23 Nov 2003	BADPIX_SUSI_20031123_1x1.pl	BADPIX_SUSI_20031123_2x2.pl	BADPIX_SUSI_20031123_1x1.tar.gz	BADPIX_SUSI_20031123_2x2.tar.gz

[*] Data taken May 29 2003 . 2x2 binning Note: This is before SUSI2 produced Multi-extension fits files!

How to use the BADPIX masks

The file you download is either a single badpix mask, or 2 badpix masks tarred and gzipped. None of these files has been trimmed. You must use them on untrimmed data, or trim them to the same size as your data.
Note: these files are NOT a perl script (though the labelling is misleading). This is the file that you indicate in the FIXFILE keyword of CCDPROC .
Simply enter the name of the badpix file there and run CCDPROC . That's all there is to it!

BADPIX masks for SUSI2 on the NTT