The muse_exp_align recipe

muse_exp_align

Synopsis

Create a coordinate offset table to be used to align exposures during exposure combination.

Description

Compute the coordinate offset for each input field-of-view image with respect to a reference. The created list of coordinate offsets can then be used in muse_exp_combine as the field coordinate offsets to properly align the exposures during their combination.

Constructor

cpl.Recipe("muse_exp_align")

Create an object for the recipe muse_exp_align.

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

Parameters

muse_exp_align.param.rsearch

Search radius (in arcsec) for each iteration of the offset computation. (str; default: ‘30.,4.,2.,0.8’) [default=”30.,4.,2.,0.8”].

muse_exp_align.param.nbins

Number of bins to use for 2D histogram on the first iteration of the offset computation. (int; default: 60) [default=60].

muse_exp_align.param.weight

Use weighting. (bool; default: True) [default=True].

muse_exp_align.param.fwhm

FWHM in pixels of the convolution filter. (float; default: 5.0) [default=5.0].

muse_exp_align.param.threshold

Initial intensity threshold for detecting point sources in sigma above background RMS. (float; default: 15.0) [default=15.0].

muse_exp_align.param.step

Increment/decrement of the threshold value in subsequent iterations. (float; default: 0.5) [default=0.5].

muse_exp_align.param.iterations

Maximum number of iterations used for detecting sources. (int; default: 100000) [default=100000].

muse_exp_align.param.srcmin

Minimum number of sources which must be found. (int; default: 5) [default=5].

muse_exp_align.param.srcmax

Maximum number of sources which may be found. (int; default: 80) [default=80].

muse_exp_align.param.roundmin

Lower limit of the allowed point-source roundness. (float; default: -1.0) [default=-1.0].

muse_exp_align.param.roundmax

Upper limit of the allowed point-source roundness. (float; default: 1.0) [default=1.0].

muse_exp_align.param.sharpmin

Lower limit of the allowed point-source sharpness. (float; default: 0.2) [default=0.2].

muse_exp_align.param.sharpmax

Upper limit of the allowed point-source sharpness. (float; default: 1.0) [default=1.0].

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

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

muse_exp_align.param.rsearch = "30.,4.,2.,0.8"
muse_exp_align.param.nbins = 60
muse_exp_align.param.weight = True
muse_exp_align.param.fwhm = 5.0
muse_exp_align.param.threshold = 15.0
muse_exp_align.param.step = 0.5
muse_exp_align.param.iterations = 100000
muse_exp_align.param.srcmin = 5
muse_exp_align.param.srcmax = 80
muse_exp_align.param.roundmin = -1.0
muse_exp_align.param.roundmax = 1.0
muse_exp_align.param.sharpmin = 0.2
muse_exp_align.param.sharpmax = 1.0

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

import cpl
muse_exp_align = cpl.Recipe("muse_exp_align")
[...]
res = muse_exp_align( ..., param = {"rsearch":"30.,4.,2.,0.8", "nbins":60})

See also

cpl.Recipe for more information about the recipe object.

Bug reports

Please report any problems to Ralf Palsa. Alternatively, you may send a report to the ESO User Support Department.