The uves_cal_mflat recipe =============================================================== .. data:: uves_cal_mflat Synopsis -------- Creates the master flat field frame Description ----------- This recipe creates a master flat frame by 1) subtracting the master bias frame from each flat field frame, 2) dividing each flat field frame by the exposure time for that frame, 3) taking the median of all bias subtracted, normalized raw flat frames, 4) optionally subtracting the master dark frame, and 5) subtracting the background to get the bias subtracted, optionally dark subtracted, normalized, background subtracted master flat-field frame. Symbolically, masterflat = median( (flat_i - masterbias)/exptime_i ) - masterdark/exptime - background. The input flat field frames must have same tag which must match (I|D|S|T|SCREEN|)FLAT_(BLUE|RED), for example TFLAT_BLUE or FLAT_RED. Also, a master bias (MASTER_BIAS_xxxx) and ordertable (ORDER_TABLE_xxxx) must be provided for each chip (xxxx = BLUE, REDL, REDU). A master dark frame (MASTER_(P)DARK_xxxx) may optionally be provided. On blue input the recipe computes one master flat field frame; on red input the recipe produces a master flat field frame for each chip (MASTER_FLAT_xxxx, MASTER_IFLAT_xxxx, MASTER_DFLAT_xxxx, MASTER_TFLAT_xxxx or MASTER_SCREEN_FLAT_xxxx). Constructor ----------- .. method:: cpl.Recipe("uves_cal_mflat") :noindex: Create an object for the recipe uves_cal_mflat. :: import cpl uves_cal_mflat = cpl.Recipe("uves_cal_mflat") Parameters ---------- .. py:attribute:: uves_cal_mflat.param.backsub.mmethod Background measuring method. If equal to 'median' the background is sampled using the median of a subwindow. If 'minimum', the subwindow minimum value is used. If 'no', no background subtraction is done. (str; default: 'median') [default="median"]. .. py:attribute:: uves_cal_mflat.param.backsub.npoints This is the number of columns in interorder space used to sample the background. (int; default: 82) [default=82]. .. py:attribute:: uves_cal_mflat.param.backsub.radiusy The height (in pixels) of the background sampling window is (2*radiusy + 1). This parameter is not corrected for binning. (int; default: 2) [default=2]. .. py:attribute:: uves_cal_mflat.param.backsub.sdegree Degree of interpolating splines. Currently only degree = 1 is supported (int; default: 1) [default=1]. .. py:attribute:: uves_cal_mflat.param.backsub.smoothx If spline interpolation is used to measure the background, the x-radius of the post-smoothing window is (smoothx * image_width). Here, 'image_width' is the image width after binning. If negative, the default values are used: (25.0/4096) for blue flat-field frames, (50.0/4096) for red flat-field frames, (300.0/4096) for blue science frames and (300.0/4096) for red science frames. (float; default: -1.0) [default=-1.0]. .. py:attribute:: uves_cal_mflat.param.backsub.smoothy If spline interpolation is used to measure the background, the y-radius of the post-smoothing window is (smoothy * image_height). Here, 'image_height' is the image height after binning. If negative, the default values are used: (100.0/2048) for blue flat-field frames, (300.0/2048) for red flat-field frames, (200.0/2048) for blue science frames and (500.0/2048) for red science frames. (float; default: -1.0) [default=-1.0]. .. py:attribute:: uves_cal_mflat.param.debug Whether or not to save intermediate results to local directory (bool; default: False) [default=False]. .. py:attribute:: uves_cal_mflat.param.norm_method Method used to build master frame (str; default: 'explevel') [default="explevel"]. .. py:attribute:: uves_cal_mflat.param.plotter Any plots produced by the recipe are redirected to the command specified by this parameter. The plotting command must contain the substring 'gnuplot' and must be able to parse gnuplot syntax on its standard input. Valid examples of such a command may include 'gnuplot -persist' and 'cat > mygnuplot$$.gp'. A finer control of the plotting options can be obtained by writing an executable script, e.g. my_gnuplot.pl, that executes gnuplot after setting the desired gnuplot options (e.g. set terminal pslatex color). To turn off plotting, set this parameter to 'no' (str; default: 'no') [default="no"]. .. py:attribute:: uves_cal_mflat.param.process_chip For RED arm data process the redl, redu, or both chip(s) (str; default: 'both') [default="both"]. The following code snippet shows the default settings for the available parameters. :: import cpl uves_cal_mflat = cpl.Recipe("uves_cal_mflat") uves_cal_mflat.param.backsub.mmethod = "median" uves_cal_mflat.param.backsub.npoints = 82 uves_cal_mflat.param.backsub.radiusy = 2 uves_cal_mflat.param.backsub.sdegree = 1 uves_cal_mflat.param.backsub.smoothx = -1.0 uves_cal_mflat.param.backsub.smoothy = -1.0 uves_cal_mflat.param.debug = False uves_cal_mflat.param.norm_method = "explevel" uves_cal_mflat.param.plotter = "no" uves_cal_mflat.param.process_chip = "both" You may also set or overwrite some or all parameters by the recipe parameter `param`, as shown in the following example: :: import cpl uves_cal_mflat = cpl.Recipe("uves_cal_mflat") [...] res = uves_cal_mflat( ..., param = {"backsub.mmethod":"median", "backsub.npoints":82}) .. seealso:: `cpl.Recipe `_ for more information about the recipe object. Bug reports ----------- Please report any problems to `Jonas M. Larsen `_. Alternatively, you may send a report to the `ESO User Support Department `_. Copyright --------- This file is part of the FLAMES/UVES Pipeline Copyright (C) 2004, 2005, 2006, 2007 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:: Jonas M. Larsen