BADPIX masks for EMMI-RED
on the NTT

Description

This page contains BADPIX masks for EMMI_RED

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 EMMI-RED. NOTE: The masks for EMMI-RED 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 EMMI-RED 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 EMMI-RED
1. One where the EMMI-RED MEF files are later split into individual chips. This is useful if you wish to reduce the two EMMI-RED chips individually.
2. One where the EMMI-RED MEF files are first converted into single FITS files with inemmi.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 EMMI-RED 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 EMMI-RED file:
- run inemmi.prg (produces FLATLHRATIOsingle.fits)
Create the BADPIX masks using the parameters for ccdmask listed below:
1. ccdmask FLATLHRATIOsingle.fits BADPIX_EMMI_date.pl
2. ccdmask FLATLHRATIO_1.fits BADPIX_EMMI_date_1.pl
  ccdmask FLATLHRATIO_2.fits BADPIX_EMMI_date_2.pl
BADPIX masks are only made for 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 EMMI-RED MEF images merged into a simple FITS file with inemmi.prg	4 separate, untrimmed pixel list files for reducing the EMMI-RED chips separately
	2x2 binning	2x2 binning
13 March 2004	BADPIX_EMMI_20040313.pl	BADPIX_EMMI_20040313.tar.gz
2 June 2003	BADPIX_EMMI_20030602.pl

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!