DcrAssembleCoaddTask

Python API summary

from lsst.pipe.tasks.dcrAssembleCoadd import DcrAssembleCoaddTask
classDcrAssembleCoaddTask(*args, **kwargs)

Assemble DCR coadded images from a set of warps...

attributeconfig

Access configuration fields and retargetable subtasks.

methodrun(skyInfo, warpRefList, imageScalerList, weightList, supplementaryData=None)

Assemble the coadd...

methodrunDataRef(dataRef, selectDataList=None, warpRefList=None)

Assemble a coadd from a set of warps...

See also

See the DcrAssembleCoaddTask API reference for complete details.

Retargetable subtasks

assembleStaticSkyModel

Default
lsst.pipe.tasks.assembleCoadd.AssembleCoaddTask
Field type
ConfigurableField
Task to assemble an artifact-free, PSF-matched Coadd to serve as a naive/first-iteration model of the static sky.

detect

Default
lsst.meas.algorithms.detection.SourceDetectionTask
Field type
ConfigurableField
Detect outlier sources on difference between each psfMatched warp and static sky model

detectPsfSources

Default
lsst.meas.algorithms.detection.SourceDetectionTask
Field type
ConfigurableField
Task to detect sources for PSF measurement, if doCalculatePsf is set.

detectTemplate

Default
lsst.meas.algorithms.detection.SourceDetectionTask
Field type
ConfigurableField
Detect sources on static sky model. Only used if doPreserveContainedBySource is True

inputRecorder

Default
lsst.pipe.tasks.coaddInputRecorder.CoaddInputRecorderTask
Field type
ConfigurableField
Subtask that helps fill CoaddInputs catalogs added to the final Exposure

interpImage

Default
lsst.pipe.tasks.interpImage.InterpImageTask
Field type
ConfigurableField
Task to interpolate (and extrapolate) over NaN pixels

maskStreaks

Default
lsst.pipe.tasks.maskStreaks.MaskStreaksTask
Field type
ConfigurableField
Detect streaks on difference between each psfMatched warp and static sky model. Only used if doFilterMorphological is True. Adds a mask plane to an exposure, with the mask plane name set bystreakMaskName

measurePsf

Default
lsst.pipe.tasks.measurePsf.MeasurePsfTask
Field type
ConfigurableField
Task to measure the PSF of the coadd, if doCalculatePsf is set.

measurePsfSources

Default
lsst.meas.base.sfm.SingleFrameMeasurementTask
Field type
ConfigurableField
Task to measure sources for PSF measurement, if doCalculatePsf is set.

modelPsf

Default
lsst.meas.algorithms.gaussianPsfFactory.applyWrapper
Field type
ConfigurableField
Model Psf factory

scaleWarpVariance

Default
lsst.pipe.tasks.scaleVariance.ScaleVarianceTask
Field type
ConfigurableField
Rescale variance on warps

scaleZeroPoint

Default
lsst.pipe.tasks.scaleZeroPoint.ScaleZeroPointTask
Field type
ConfigurableField
Task to adjust the photometric zero point of the coadd temp exposures

select

Default
lsst.pipe.tasks.selectImages.WcsSelectImagesTask
Field type
ConfigurableField
Image selection subtask.

Configuration fields

accelerateModel

Default
3
Field type
float Field
Factor to amplify the differences between model planes by to speed convergence.

badMaskPlanes

Default
('NO_DATA',)
Field type
str ListField
Mask planes that, if set, the associated pixel should not be included in the coaddTempExp.

bandwidth

Default
None
Field type
float Field
Bandwidth of the physical filter, in nm.Required if transmission curves aren’t used.Support for using transmission curves is to be added in DM-13668.

baseGain

Default
None
Field type
float Field (optional)
Relative weight to give the new solution vs. the last solution when updating the model.A value of 1.0 gives equal weight to both solutions.Small values imply slower convergence of the solution, but can help prevent overshooting and failures in the fit.If baseGain is None, a conservative gain will be calculated from the number of subfilters.

brightObjectMaskName

Default
'BRIGHT_OBJECT'
Field type
str Field
Name of mask bit used for bright objects

calcErrorFromInputVariance

Default
True
Field type
bool Field
Calculate coadd variance from input variance by stacking statistic.Passed to StatisticsControl.setCalcErrorFromInputVariance()

clipIter

Default
2
Field type
int Field
Number of iterations of outlier rejection; ignored if non-clipping statistic selected.

coaddName

Default
'deep'
Field type
str Field
Coadd name: typically one of deep or goodSeeing.

coaddPsf

Data type
lsst.meas.algorithms.coaddPsf.coaddPsf.CoaddPsfConfig
Field type
ConfigField
Configuration for CoaddPsf

connections

Data type
lsst.pipe.base.config.Connections
Field type
ConfigField
Configurations describing the connections of the PipelineTask to datatypes

convergenceMaskPlanes

Default
['DETECTED']
Field type
str ListField
Mask planes to use to calculate convergence.

convergenceThreshold

Default
0.001
Field type
float Field
Target relative change in convergence between iterations of forward modeling.

dcrNumSubfilters

Default
3
Field type
int Field
Number of sub-filters to forward model chromatic effects to fit the supplied exposures.

doAirmassWeight

Default
False
Field type
bool Field
Weight exposures by airmass? Useful if there are relatively few high-airmass observations.

doApplyExternalPhotoCalib

Default
False
Field type
bool Field
Whether to apply external photometric calibration via an lsst.afw.image.PhotoCalib object. Uses the externalPhotoCalibName field to determine which calibration to load.

doApplyExternalSkyWcs

Default
False
Field type
bool Field
Whether to apply external astrometric calibration via an lsst.afw.geom.SkyWcs object. Uses externalSkyWcsName field to determine which calibration to load.

doApplyUberCal

Default
False
Field type
bool Field
Apply ubercalibrated WCS and PhotoCalib results to input calexps? This field is no longer used, and has been deprecated by DM-21308. It will be removed after v20. Use doApplyExternalPhotoCalib and doApplyExternalSkyWcs instead.

doAttachTransmissionCurve

Default
False
Field type
bool Field
Attach a piecewise TransmissionCurve for the coadd? (requires all input Exposures to have TransmissionCurves).

doCalculatePsf

Default
False
Field type
bool Field
Set to detect stars and recalculate the PSF from the final coadd.Otherwise the PSF is estimated from a selection of the best input exposures

doFilterMorphological

Default
False
Field type
bool Field
Filter artifact candidates based on morphological criteria, i.g. those that appear to be streaks.

doInterp

Default
True
Field type
bool Field
Interpolate over NaN pixels? Also extrapolate, if necessary, but the results are ugly.

doMaskBrightObjects

Default
False
Field type
bool Field
Set mask and flag bits for bright objects?

doNImage

Default
False
Field type
bool Field
Create image of number of contributing exposures for each pixel

doPrefilterArtifacts

Default
True
Field type
bool Field
Ignore artifact candidates that are mostly covered by the bad pixel mask, because they will be excluded anyway. This prevents them from contributing to the outlier epoch count image and potentially being labeled as persistant.’Mostly’ is defined by the config ‘prefilterArtifactsRatio’.

doPreserveContainedBySource

Default
True
Field type
bool Field
Rescue artifacts from clipping that completely lie within a footprint detectedon the PsfMatched Template Coadd. Replicates a behavior of SafeClip.

doPsfMatch

Default
False
Field type
bool Field
Match to modelPsf? Deprecated. Sets makePsfMatched=True, makeDirect=False

doScaleWarpVariance

Default
True
Field type
bool Field
Rescale Warp variance plane using empirical noise?

doSigmaClip

Default
False
Field type
bool Field
Perform sigma clipped outlier rejection with MEANCLIP statistic? (DEPRECATED)

doUsePsfMatchedPolygons

Default
False
Field type
bool Field
Use ValidPolygons from shrunk Psf-Matched Calexps? Should be set to True by CompareWarp only.

doWrite

Default
True
Field type
bool Field
Persist coadd?

effectiveWavelength

Default
None
Field type
float Field
Effective wavelength of the filter, in nm.Required if transmission curves aren’t used.Support for using transmission curves is to be added in DM-13668.

externalPhotoCalibName

Default
'jointcal'
Field type
str ChoiceField (optional)
Choices
'jointcal'
Use jointcal_photoCalib
'fgcm'
Use fgcm_photoCalib
'fgcm_tract'
Use fgcm_tract_photoCalib
None
Field is optional
Type of external PhotoCalib if doApplyExternalPhotoCalib is True.

externalSkyWcsName

Default
'jointcal'
Field type
str ChoiceField (optional)
Choices
'jointcal'
Use jointcal_wcs
None
Field is optional
Type of external SkyWcs if doApplyExternalSkyWcs is True.

hasFakes

Default
False
Field type
bool Field
Should be set to True if fake sources have been inserted into the input data.

imageInterpOrder

Default
3
Field type
int Field
The order of the spline interpolation used to shift the image plane.

includeCalibVar

Default
False
Field type
bool Field
Add photometric calibration variance to warp variance plane.

maskPropagationThresholds

Default
{'SAT': 0.1}
Field type
DictField
Key type
str
Value type
float
Threshold (in fractional weight) of rejection at which we propagate a mask plane to the coadd; that is, we set the mask bit on the coadd if the fraction the rejected frames would have contributed exceeds this value.

matchingKernelSize

Default
21
Field type
int Field
Size in pixels of matching kernel. Must be odd.

maxFractionEpochsHigh

Default
0.03
Field type
float RangeField
Range
[0.0,1.0)
Fraction of local number of epochs (N) to use as effective maxNumEpochs for high N. Effective maxNumEpochs = min(maxFractionEpochsLow * N, maxNumEpochs + maxFractionEpochsHigh * N)

maxFractionEpochsLow

Default
0.4
Field type
float RangeField
Range
[0.0,1.0)
Fraction of local number of epochs (N) to use as effective maxNumEpochs for low N. Effective maxNumEpochs = min(maxFractionEpochsLow * N, maxNumEpochs + maxFractionEpochsHigh * N)

maxNumEpochs

Default
2
Field type
int Field
Charactistic maximum local number of epochs/visits in which an artifact candidate can appear and still be masked. The effective maxNumEpochs is a broken linear function of local number of epochs (N): min(maxFractionEpochsLow*N, maxNumEpochs + maxFractionEpochsHigh*N). For each footprint detected on the image difference between the psfMatched warp and static sky model, if a significant fraction of pixels (defined by spatialThreshold) are residuals in more than the computed effective maxNumEpochs, the artifact candidate is deemed persistant rather than transient and not masked.

maxNumIter

Default
None
Field type
int Field (optional)
Maximum number of iterations of forward modeling.

minNumIter

Default
None
Field type
int Field (optional)
Minimum number of iterations of forward modeling.

modelWeightsWidth

Default
3
Field type
float Field
Width of the region around detected sources to include in the DcrModel.

prefilterArtifactsMaskPlanes

Default
('NO_DATA', 'BAD', 'SAT', 'SUSPECT')
Field type
str ListField
Prefilter artifact candidates that are mostly covered by these bad mask planes.

prefilterArtifactsRatio

Default
0.05
Field type
float Field
Prefilter artifact candidates with less than this fraction overlapping good pixels

regularizationWidth

Default
2
Field type
int Field
Minimum radius of a region to include in regularization, in pixels.

regularizeModelFrequency

Default
4.0
Field type
float Field
Maximum relative change of the model allowed between subfilters.Set to zero to disable.

regularizeModelIterations

Default
2.0
Field type
float Field
Maximum relative change of the model allowed between iterations.Set to zero to disable.

removeMaskPlanes

Default
['NOT_DEBLENDED']
Field type
str ListField
Mask planes to remove before coadding

saveMetadata

Default
True
Field type
bool Field
Flag to enable/disable metadata saving for a task, enabled by default.

sigmaClip

Default
3.0
Field type
float Field
Sigma for outlier rejection; ignored if non-clipping statistic selected.

spatialThreshold

Default
0.5
Field type
float RangeField
Range
[0.0,1.0]
Unitless fraction of pixels defining how much of the outlier region has to meet the temporal criteria. If 0, clip all. If 1, clip none.

splitSubfilters

Default
True
Field type
bool Field
Calculate DCR for two evenly-spaced wavelengths in each subfilter.Instead of at the midpoint

splitThreshold

Default
0.1
Field type
float Field
Minimum DCR difference within a subfilter to use splitSubfilters, in pixels.Set to 0 to always split the subfilters.

statistic

Default
'MEANCLIP'
Field type
str Field
Main stacking statistic for aggregating over the epochs.

streakMaskName

Default
'STREAK'
Field type
str Field
Name of mask bit used for streaks

subregionSize

Default
(2000, 2000)
Field type
int ListField
Required length
2
Width, height of stack subregion size; make small enough that a full stack of images will fit into memory at once.

useConvergence

Default
True
Field type
bool Field
Use convergence test as a forward modeling end condition?If not set, skips calculating convergence and runs for maxNumIter iterations

useModelWeights

Default
True
Field type
bool Field
Width of the region around detected sources to include in the DcrModel.

useProgressiveGain

Default
True
Field type
bool Field
Use a gain that slowly increases above baseGain to accelerate convergence? When calculating the next gain, we use up to 5 previous gains and convergence values.Can be set to False to force the model to change at the rate of baseGain.

warpType

Default
'direct'
Field type
str Field
Warp name: one of ‘direct’ or ‘psfMatched’