AmpOffsetConfig#

class lsst.ip.isr.AmpOffsetConfig(*args, **kw)#

Bases: Config

Configuration parameters for AmpOffsetTask.

Attributes Summary

`ampEdgeInset`	Number of pixels the amp edge strip is inset from the amp edge.
`ampEdgeMaxOffset`	Maximum allowed amp offset ADU value.
`ampEdgeMinFrac`	Minimum allowed fraction of viable pixel rows along an amp edge.
`ampEdgeWidth`	Pixel width of the amp edge strip, starting at ampEdgeInset and extending inwards.
`ampEdgeWindowFrac`	Fraction of the amp edge lengths utilized as the sliding window for generating rolling average amp offset values.
`applyWeights`	Weights the amp offset calculation by the length of the interface between amplifiers.
`background`	An initial background estimation step run prior to amp offset calculation.
`backgroundFractionSample`	The fraction of the shorter side of the amplifier used for background binning.
`detection`	Source detection to add temporary detection footprints prior to amp offset calculation.
`doApplyAmpOffset`	Apply amp offset corrections to the input exposure? (`bool`, default `False`)
`doBackground`	Estimate and subtract background prior to amp offset estimation? (`bool`, default `True`)
`doDetection`	Detect sources and update cloned exposure prior to amp offset estimation? (`bool`, default `True`)
`doWindowSmoothing`	Smooth amp edge differences by taking a rolling average.

Methods Summary

`setDefaults`()	Subclass hook for computing defaults.
`validate`()	Validate the Config, raising an exception if invalid.

Attributes Documentation

ampEdgeInset#: Number of pixels the amp edge strip is inset from the amp edge. A thin strip of pixels running parallel to the edge of the amp is used to characterize the average flux level at the amp edge. (int, default 5)

ampEdgeMaxOffset#: Maximum allowed amp offset ADU value. If a measured amp offset value is larger than this, the result will be discarded and therefore not used to determine amp pedestal corrections. (float, default 5.0)

ampEdgeMinFrac#: Minimum allowed fraction of viable pixel rows along an amp edge. No amp offset estimate will be generated for amp edges that do not have at least this fraction of unmasked pixel rows. (float, default 0.5)

ampEdgeWidth#: Pixel width of the amp edge strip, starting at ampEdgeInset and extending inwards. (int, default 64)

ampEdgeWindowFrac#: Fraction of the amp edge lengths utilized as the sliding window for generating rolling average amp offset values. It should be reconfigured for every instrument (HSC, LSSTCam, etc.) and should not exceed 1. If not provided, it defaults to the fraction that recovers the pixel size of the sliding window used in obs_subaru for compatibility with existing HSC data. Only relevant if doWindowSmoothing is set to True. (float, default 0.12260536398467432)

applyWeights#: Weights the amp offset calculation by the length of the interface between amplifiers. Applying weights does not affect outcomes for amplifiers in a 2D grid with square-shaped amplifiers or in any 1D layout on a detector, regardless of whether the amplifiers are square. (bool, default True)

background#: An initial background estimation step run prior to amp offset calculation. (ConfigurableInstance, default <class 'lsst.meas.algorithms.subtractBackground.SubtractBackgroundConfig'>)

backgroundFractionSample#: The fraction of the shorter side of the amplifier used for background binning. (float, default 1.0)

detection#: Source detection to add temporary detection footprints prior to amp offset calculation. (ConfigurableInstance, default <class 'lsst.meas.algorithms.detection.SourceDetectionConfig'>)

doApplyAmpOffset#: Apply amp offset corrections to the input exposure? (bool, default False)

doBackground#: Estimate and subtract background prior to amp offset estimation? (bool, default True)

doDetection#: Detect sources and update cloned exposure prior to amp offset estimation? (bool, default True)

doWindowSmoothing#: Smooth amp edge differences by taking a rolling average. (bool, default True)

Methods Documentation

setDefaults()#: Subclass hook for computing defaults.

Notes#

Derived Config classes that must compute defaults rather than using the Field instances’s defaults should do so here. To correctly use inherited defaults, implementations of setDefaults must call their base class’s setDefaults.

validate()#

Validate the Config, raising an exception if invalid.

Raises#

lsst.pex.config.FieldValidationError: Raised if verification fails.

Notes#

The base class implementation performs type checks on all fields by calling their validate methods.

Complex single-field validation can be defined by deriving new Field types. For convenience, some derived lsst.pex.config.Field-types (ConfigField and ConfigChoiceField) are defined in lsst.pex.config that handle recursing into subconfigs.

Inter-field relationships should only be checked in derived Config classes after calling this method, and base validation is complete.