NAME

       fors_spec_mflat - Computes master spectroscopic flat, removing bias first

SYNOPSIS

       esorex fors_spec_mflat [OPTIONS] FILE.sof

DESCRIPTION

       This  recipe is used to subtract the master bias, produced by the recipe fors_bias, from a
       set of raw flat field frames. The input raw frames are summed, the master  bias  frame  is
       rescaled  accordingly,  and  subtracted from the result. The overscan regions, if present,
       are used to compensate for variations of the bias level between master bias and input  raw
       frames.

       The overscan regions are then trimmed from the result.

       In the table below the MXU acronym can be alternatively read as MOS and LSS.

       Input files:

         DO category:               Type:       Explanation:         Required:
         SCREEN_FLAT_MXU            Raw         Raw data frame          Y
         SLIT_LOCATION_MXU          Calib       Slits positions on CCD  Y
         CURV_COEFF_MXU             Calib       Slits tracing fits      Y
         DISP_COEFF_MXU             Calib       Wavelength calibration  Y
         MASTER_BIAS                Calib       Master bias frame       Y

       Output files:

         DO category:               Data type:  Explanation:
         MASTER_SCREEN_FLAT_MXU     FITS image  Bias subtracted sum frame

OPTIONS

       --smooth_sed <float>
              Smoothing  size  for  each  flat  sed  (float; default: 0.0). The full name of this
              option  for  the  EsoRex  configuration  file  is   fors.fors_spec_mflat.smooth_sed
              [default = 0.0].

       --stack_method <str>
              Frames  combination  method (str; default: ´sum´). The full name of this option for
              the EsoRex configuration file is fors.fors_spec_mflat.stack_method [default = sum].

       --klow <float>
              Low threshold in ksigma method (float; default: 3.0). The full name of this  option
              for the EsoRex configuration file is fors.fors_spec_mflat.klow [default = 3.0].

       --khigh <float>
              High threshold in ksigma method (float; default: 3.0). The full name of this option
              for the EsoRex configuration file is fors.fors_spec_mflat.khigh [default = 3.0].

       --kiter <long>
              Max number of iterations in ksigma method (long; default: 999). The  full  name  of
              this  option  for  the  EsoRex  configuration  file  is  fors.fors_spec_mflat.kiter
              [default = 999].

       --nonlinear_level <float>
              Level above which the detector is not linear (float; default:  50000.0).  The  full
              name    of    this    option    for    the    EsoRex    configuration    file    is
              fors.fors_spec_mflat.nonlinear_level [default = 50000.0].

       --max_nonlinear_ratio <float>
              Maximum allowed ratio of non-linear pixels per slit (float; default: 0.2). The full
              name    of    this    option    for    the    EsoRex    configuration    file    is
              fors.fors_spec_mflat.max_nonlinear_ratio [default = 0.2].

       Note that it is possible to create a configuration file containing  these  options,  along
       with  suitable default values. Please refer to the details provided by the 'esorex --help'
       command.

SEE ALSO

       The full documentation for the fors pipeline can be downloaded as a  PDF  file  using  the
       following URL:

              ftp://ftp.eso.org/pub/dfs/pipelines/fors/fors-pipeline-manual-4.9.pdf

       An   overview   over   the   existing   ESO  pipelines  can  be  found  on  the  web  page
       http://www.eso.org/sci/software/pipelines/.

       Basic documentation about the EsoRex program can be found at the esorex (1) man page.

       It is possible to call the pipelines  from  python  using  the  python-cpl  package.   See
       http://packages.python.org/python-cpl/index.html for further information.

       The  other  recipes  of  the  fors  pipeline are fors_align_sky(7), fors_align_sky_lss(7),
       fors_bias(7),   fors_calib(7),   fors_config(7),   fors_dark(7),   fors_detect_objects(7),
       fors_detect_spectra(7),  fors_extract(7),  fors_extract_objects(7), fors_extract_slits(7),
       fors_flatfield(7),  fors_img_science(7),  fors_img_screen_flat(7),   fors_img_sky_flat(7),
       fors_normalise_flat(7),   fors_photometry(7),   fors_pmos_calib(7),  fors_pmos_extract(7),
       fors_pmos_science(7),     fors_remove_bias(7),     fors_resample(7),      fors_science(7),
       fors_subtract_sky(7),   fors_subtract_sky_lss(7),   fors_sumflux(7),   fors_trace_flat(7),
       fors_wave_calib(7), fors_wave_calib_lss(7), fors_zeropoint(7)

VERSION

       fors_spec_mflat 5.3.23

AUTHOR

       Carlo Izzo <usd-help@eso.org>

BUG REPORTS

       Please report any problems to usd-help@eso.org. Alternatively, you may send  a  report  to
       the ESO User Support Department <usd-help@eso.org>.

LICENSE

       This  file  is  currently  part  of  the  FORS Instrument Pipeline Copyright (C) 2002-2011
       European Southern Observatory

       This program is free software; you can redistribute it and/or modify it under the terms of
       the  GNU  General  Public  License  as  published  by the Free Software Foundation; either
       version 2 of the License, or (at your option) any later version.

       This program is distributed in the hope that it will be useful, but WITHOUT ANY  WARRANTY;
       without  even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
       See the GNU General Public License for more details.

       You should have received a copy of the GNU General Public License along with this program;
       if  not, write to the Free Software Foundation, Inc., 51 Franklin St, Fifth Floor, Boston,
       MA  02110-1301  USA