The naco_img_twflat recipe
===============================================================

.. data:: naco_img_twflat

Synopsis
--------

Twilight flat recipe

Description
-----------

naco_img_twflat -- NACO imaging flat-field creation from twilight images.

The files listed in the Set Of Frames (sof-file) must be tagged:
raw-file.fits CAL_FLAT_TW or
raw-or-calib-file.fits CAL_DARK
The flat frames are divided into groups, each group having identical instrument settings. Each group of flats is reduced independently of each other. For each group of flats, the set of frames shall contain either zero, one or n dark frames with the same instrument settings, where n is the number of flats in the group.


Constructor
-----------

.. method:: cpl.Recipe("naco_img_twflat")
   :noindex:

   Create an object for the recipe naco_img_twflat.

::

   import cpl
   naco_img_twflat = cpl.Recipe("naco_img_twflat")

Parameters
----------

.. py:attribute:: naco_img_twflat.param.r

    Rejected left right bottom and top border [pixel] (str; default: '200  200 200 200') [default="200 200 200 200"].
.. py:attribute:: naco_img_twflat.param.t

    Low and high thresholds for the Bad Pixel Map (str; default: '0.5  2.0') [default="0.5 2.0"].
.. py:attribute:: naco_img_twflat.param.prop

    Use the proportional fit (bool; default: False) [default=False].
.. py:attribute:: naco_img_twflat.param.bpm

    Create the bad pixel map (bool; default: False) [default=False].
.. py:attribute:: naco_img_twflat.param.errmap

    Create the error map (bool; default: False) [default=False].
.. py:attribute:: naco_img_twflat.param.intercept

    Create the intercept image (bool; default: False) [default=False].


The following code snippet shows the default settings for the available 
parameters.

::

   import cpl
   naco_img_twflat = cpl.Recipe("naco_img_twflat")

   naco_img_twflat.param.r = "200 200 200 200"
   naco_img_twflat.param.t = "0.5 2.0"
   naco_img_twflat.param.prop = False
   naco_img_twflat.param.bpm = False
   naco_img_twflat.param.errmap = False
   naco_img_twflat.param.intercept = False


You may also set or overwrite some or all parameters by the recipe 
parameter `param`, as shown in the following example:

::

   import cpl
   naco_img_twflat = cpl.Recipe("naco_img_twflat")
   [...]
   res = naco_img_twflat( ..., param = {"r":"200 200 200 200", "t":"0.5 2.0"})


.. seealso:: `cpl.Recipe <http://packages.python.org/python-cpl/recipe.html>`_
   for more information about the recipe object.

Bug reports
-----------

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

Copyright
---------

This file is part of the NACO Instrument Pipeline
Copyright (C) 2002, 2003, 2005, 2008 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  02111-1307  USA

.. codeauthor:: Lars Lundin <llundin@eso.org>
