The kmos_illumination recipe

kmos_illumination

Synopsis

Create a frame to correct spatial non-uniformity of flatfield

Description

This recipe creates the spatial non-uniformity calibration frame needed for all three detectors. It must be called after the kmo_wave_cal-recipe, which generates the spectral calibration frame needed in this recipe. As input at least a sky or flat, a master dark, a master flat and the spatial and spectral calibration frames are required.

The created product, the illumination correction, can be used as input for kmo_std_star and kmo_sci_red.

Input files

DO CATG           Type   Explanation                    Required #Frames
--------          -----  -----------                    -------- -------
FLAT_SKY           F2D   Sky exposures                     Y      1-n
                         (at least 3 frames recommended)
or FLAT_ON F2D Flat exposures Y 1-n
(at least 3 frames recommended)

MASTER_DARK F2D Master dark Y 1 MASTER_FLAT F2D Master flat Y 1 XCAL F2D x calibration frame Y 1 YCAL F2D y calibration frame Y 1 LCAL F2D Wavelength calib. frame Y 1 WAVE_BAND F2L Table with start-/end-wavelengths Y 1 FLAT_EDGE F2L Table with fitted slitlet edges N 0,1

Output files

DO CATG           Type   Explanation
--------          -----  -----------
ILLUM_CORR        F2I    Illumination calibration frame
If FLAT_EDGE is provided:
SKYFLAT_EDGE      F2L    Frame containing parameters of fitted
                         slitlets of all IFUs of all detectors

Constructor

cpl.Recipe("kmos_illumination")

Create an object for the recipe kmos_illumination.

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

Parameters

kmos_illumination.param.used_flat_type

Type (sky/lamp) of input to use: (only if 2 types in input) (str; default: ‘sky’) [default=”sky”].

kmos_illumination.param.imethod

Method to use for interpolation: [“NN” (nearest neighbour), “lwNN” (linear weighted nearest neighbor), “swNN” (square weighted nearest neighbor), “MS” (Modified Shepard’s method), “CS” (Cubic spline)] (str; default: ‘CS’) [default=”CS”].

kmos_illumination.param.neighborhoodRange

Range (pixels) to search for neighbors (float; default: 1.001) [default=1.001].

kmos_illumination.param.range

The spectral ranges to combine when collapsing the reconstructed cubes. e.g. “x1_start,x1_end;x2_start,x2_end” (microns) (str; default: ‘’) [default=”“].

kmos_illumination.param.flux

TRUE: Apply flux conservation. FALSE: otherwise (bool; default: False) [default=False].

kmos_illumination.param.add_all

FALSE: omit 1st FLAT_SKY frame (acquisition), TRUE: don’t perform any checks, add them all (bool; default: False) [default=False].

kmos_illumination.param.pix_scale

Change the pixel scale [arcsec]. Default of 0.2” results into cubes of 14x14pix, a scale of 0.1” results into cubes of 28x28pix, etc. (float; default: 0.2) [default=0.2].

kmos_illumination.param.suppress_extension

Suppress filename extension. (TRUE (apply) or FALSE (don’t apply) (bool; default: False) [default=False].

kmos_illumination.param.b_samples

The number of samples in wavelength for the reconstructed cube (int; default: 2048) [default=2048].

kmos_illumination.param.cmethod

Apply “average”, “median”, “sum”, “min_max.” or “ksigma”. (str; default: ‘ksigma’) [default=”ksigma”].

kmos_illumination.param.cpos_rej

The positive rejection threshold for kappa-sigma-clipping (sigma). (float; default: 3.0) [default=3.0].

kmos_illumination.param.cneg_rej

The negative rejection threshold for kappa-sigma-clipping (sigma). (float; default: 3.0) [default=3.0].

kmos_illumination.param.citer

The number of iterations for kappa-sigma-clipping. (int; default: 3) [default=3].

kmos_illumination.param.cmax

The number of maximum pixel values to clip with min/max-clipping. (int; default: 1) [default=1].

kmos_illumination.param.cmin

The number of minimum pixel values to clip with min/max-clipping. (int; default: 1) [default=1].

kmos_illumination.param.det

Only reduce the specified detector (int; default: 0) [default=0].

kmos_illumination.param.angle

Only reduce the specified angle (float; default: 370.0) [default=370.0].

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

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

kmos_illumination.param.used_flat_type = "sky"
kmos_illumination.param.imethod = "CS"
kmos_illumination.param.neighborhoodRange = 1.001
kmos_illumination.param.range = ""
kmos_illumination.param.flux = False
kmos_illumination.param.add_all = False
kmos_illumination.param.pix_scale = 0.2
kmos_illumination.param.suppress_extension = False
kmos_illumination.param.b_samples = 2048
kmos_illumination.param.cmethod = "ksigma"
kmos_illumination.param.cpos_rej = 3.0
kmos_illumination.param.cneg_rej = 3.0
kmos_illumination.param.citer = 3
kmos_illumination.param.cmax = 1
kmos_illumination.param.cmin = 1
kmos_illumination.param.det = 0
kmos_illumination.param.angle = 370.0

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

import cpl
kmos_illumination = cpl.Recipe("kmos_illumination")
[...]
res = kmos_illumination( ..., param = {"used_flat_type":"sky", "imethod":"CS"})

See also

cpl.Recipe for more information about the recipe object.

Bug reports

Please report any problems to Alex Agudo Berbel, Yves Jung. Alternatively, you may send a report to the ESO User Support Department.