The vmimflatsky recipe

vmimflatsky

Synopsis

Create a master sky flat field from set of raw sky flat field frames.

Description

This recipe is used to create a master sky flat field from a set of raw sky flat fields. The master sky flat field is the dataset used for the flat field correction of scientific data.

Input files

DO category:              Type:       Explanation:         Required:
IMG_SKY_FLAT              Raw         Sky flat exposure       Y
MASTER_BIAS               Calib       Master bias             Y
MASTER_DARK               Calib       Master dark             .

IMG_MASTER_SCREEN_FLAT    Calib       Master screen flat      .

CCD_TABLE                 Calib       Bad pixel table         .

Output files

DO category:              Data type:  Explanation:
IMG_MASTER_SKY_FLAT       FITS image  Master sky flat field

If a master screen flat is specified, the input sky flat exposures are flat-fielded with it, and then just used to determine the large scale trends of the instrument response; the result is then multiplied by the master screen flat. A CCD table must be specified in input only if a bad pixel cleaning is requested.

For more details, please refer to the VIMOS Pipeline User’s Guide.

Constructor

cpl.Recipe("vmimflatsky")

Create an object for the recipe vmimflatsky.

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

Parameters

vmimflatsky.param.SmoothBoxSize

Size of running box used for smoothing (int; default: 7) [default=7].

vmimflatsky.param.SmoothMethod

Smooth method for image trends removal (str; default: ‘Median’) [default=”Median”].

vmimflatsky.param.AllowSingleFrames

Frame combination method is ignored. (bool; default: True) [default=True].

vmimflatsky.param.StackMethod

Frames combination method (str; default: ‘Median’) [default=”Median”].

vmimflatsky.param.KSigmaLow

Low threshold for K-sigma clipping method (float; default: 5.0) [default=5.0].

vmimflatsky.param.KSigmaHigh

High threshold for K-sigma clipping method (float; default: 5.0) [default=5.0].

vmimflatsky.param.MinRejection

Number of lowest rejected values for rejection method (int; default: 1) [default=1].

vmimflatsky.param.MaxRejection

Number of highest rejected values for rejection method (int; default: 1) [default=1].

vmimflatsky.param.BiasMethod

Bias removal method. (str; default: ‘Zmaster’) [default=”Zmaster”].

vmimflatsky.param.CleanBadPixel

Bad pixel correction on master flat (bool; default: False) [default=False].

vmimflatsky.param.CleanCosmic

Cosmic ray events cleaning from raw flats (bool; default: False) [default=False].

vmimflatsky.param.CosmicThreshold

Threshold to identify cosmic rays candidates. (float; default: 4.0) [default=4.0].

vmimflatsky.param.CosmicRatio

Min ratio between peak and nearby pixels for a cosmic ray. (float; default: 2.0) [default=2.0].

vmimflatsky.param.ComputeQC

Compute QC1 parameters. (bool; default: True) [default=True].

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

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

vmimflatsky.param.SmoothBoxSize = 7
vmimflatsky.param.SmoothMethod = "Median"
vmimflatsky.param.AllowSingleFrames = True
vmimflatsky.param.StackMethod = "Median"
vmimflatsky.param.KSigmaLow = 5.0
vmimflatsky.param.KSigmaHigh = 5.0
vmimflatsky.param.MinRejection = 1
vmimflatsky.param.MaxRejection = 1
vmimflatsky.param.BiasMethod = "Zmaster"
vmimflatsky.param.CleanBadPixel = False
vmimflatsky.param.CleanCosmic = False
vmimflatsky.param.CosmicThreshold = 4.0
vmimflatsky.param.CosmicRatio = 2.0
vmimflatsky.param.ComputeQC = True

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

import cpl
vmimflatsky = cpl.Recipe("vmimflatsky")
[...]
res = vmimflatsky( ..., param = {"SmoothBoxSize":7, "SmoothMethod":"Median"})

See also

cpl.Recipe for more information about the recipe object.

Bug reports

Please report any problems to ESO VIMOS Pipeline Team. Alternatively, you may send a report to the ESO User Support Department.