The vmimflatscreen recipe

vmimflatscreen

Synopsis

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

Description

This recipe is used to create a master screen flat field from a set of raw screen flat fields. The master screen flat field is not used directly in the flat field correction of scientific data, but it is optionally used just in the creation of a master sky flat field by the recipe vmimflatsky.

Input files

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

CCD_TABLE                 Calib       Bad pixel table         .

Output files

DO category:              Data type:  Explanation:
IMG_MASTER_SCREEN_FLAT    FITS image  Master screen flat field
IMG_COMBINED_SCREEN_FLAT  FITS image  Combined screen flat field

The primary product is the normalised master screen flat field.

A secondary product is the combined screen flat field, that is the result of the combination of all inputs but without any normalisation applied, and is just used for data quality control. 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("vmimflatscreen")

Create an object for the recipe vmimflatscreen.

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

Parameters

vmimflatscreen.param.SmoothBoxSize

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

vmimflatscreen.param.SmoothMethod

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

vmimflatscreen.param.AllowSingleFrames

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

vmimflatscreen.param.StackMethod

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

vmimflatscreen.param.KSigmaLow

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

vmimflatscreen.param.KSigmaHigh

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

vmimflatscreen.param.MinRejection

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

vmimflatscreen.param.MaxRejection

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

vmimflatscreen.param.BiasMethod

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

vmimflatscreen.param.CleanBadPixel

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

vmimflatscreen.param.CleanCosmic

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

vmimflatscreen.param.CosmicThreshold

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

vmimflatscreen.param.CosmicRatio

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

vmimflatscreen.param.ComputeQC

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

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

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

vmimflatscreen.param.SmoothBoxSize = 7
vmimflatscreen.param.SmoothMethod = "Median"
vmimflatscreen.param.AllowSingleFrames = True
vmimflatscreen.param.StackMethod = "Average"
vmimflatscreen.param.KSigmaLow = 5.0
vmimflatscreen.param.KSigmaHigh = 5.0
vmimflatscreen.param.MinRejection = 1
vmimflatscreen.param.MaxRejection = 1
vmimflatscreen.param.BiasMethod = "Zmaster"
vmimflatscreen.param.CleanBadPixel = False
vmimflatscreen.param.CleanCosmic = False
vmimflatscreen.param.CosmicThreshold = 4.0
vmimflatscreen.param.CosmicRatio = 2.0
vmimflatscreen.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
vmimflatscreen = cpl.Recipe("vmimflatscreen")
[...]
res = vmimflatscreen( ..., 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.