DonutStamp

class lsst.ts.wep.task.DonutStamp(stamp_im: ~lsst.afw.image.maskedImage.MaskedImageF, sky_position: ~lsst.geom.SpherePoint, centroid_position: ~lsst.geom.Point2D, blend_centroid_positions: ~numpy.ndarray, defocal_type: str, defocal_distance: float, detector_name: str, cam_name: str, archive_element: ~typing.Optional[~lsst.afw.table.io.Persistable] = None, comp_im: ~lsst.ts.wep.cwfs.CompensableImage.CompensableImage = <factory>)

Bases: AbstractStamp

Single donut stamp

Parameters:

stamp_imlsst.afw.image.MaskedImageF

The actual pixel values for the postage stamp

sky_positionlsst.geom.SpherePoint

Position of the center of the stamp. Note the user must keep track of the coordinate system

centroid_positionlsst.geom.Point2D

Position of the center of the stamp in pixels

blend_centroid_positionsnumpy.ndarray

Positions of the centroids (in pixels) for sources blended with the central source

defocal_typestr

Defocal state of the stamp. “extra” or “intra” are allowed values.

defocal_distancefloat

Defocal offset of the instrument in mm.

detector_namestr

CCD where the donut is found

cam_namestr

Camera name for the stamp image. “LSSTCam” or “LSSTComCam” are available camera names currently.

archive_elementafwTable.io.Persistable, optional

Archive element (e.g. Transform or WCS) associated with this stamp. (the default is None.)

comp_imCompensableImage, init=False

CompensableImage object to create masks for the stamp. This is initialized in the __post_init__ stage of the dataclass.

mask_compafwImage.Mask, init=False

Padded Mask for use at the offset planes. This is initialized in the __post_init__ stage of the dataclass.

mask_pupilafwImage.Mask, init=False

Non-padded mask corresponding to aperture. This is initialized in the __post_init__ stage of the dataclass.

Attributes Summary

archive_element

Methods Summary

calcFieldXY()	Calculate the X, Y field position of the centroid in degrees.
factory(stamp_im, metadata, index[, ...])	This method is needed to service the FITS reader.
getCamera()	Get the proper camera object for the donuts.
makeMasks(inst, model, boundaryT, ...)	Get the binary mask which considers the obscuration and off-axis correction.

Attributes Documentation

archive_element: Optional[Persistable] = None

Methods Documentation

calcFieldXY()

Calculate the X, Y field position of the centroid in degrees.

Returns:

float

Field x position in degrees.

float

Field y position in degrees.

classmethod factory(stamp_im, metadata, index, archive_element=None)

This method is needed to service the FITS reader. We need a standard interface to construct objects like this. Parameters needed to construct this object are passed in via a metadata dictionary and then passed to the constructor of this class. They should each point to lists of values.

Parameters:

stamp_imlsst.afw.image.MaskedImage

Pixel data to pass to the constructor

metadatalsst.daf.base.PropertyList

PropertyList containing the information needed by the constructor.

indexint

Index into the lists in metadata

archive_elementafwTable.io.Persistable, optional

Archive element (e.g. Transform or WCS) associated with this stamp. (the default is None.)

Returns:

DonutStamp

An instance of this class

getCamera()

Get the proper camera object for the donuts.

Returns:

lsst.afw.cameraGeom.Camera

Camera object for the exposures.

Raises:

ValueError

The camera is not supported.

makeMasks(inst, model, boundaryT, maskScalingFactorLocal)

Get the binary mask which considers the obscuration and off-axis correction.

Parameters:

instInstrument

Instrument to use.

modelstr

Optical model. It can be “paraxial”, “onAxis”, or “offAxis”.

boundaryTint

Extended boundary in pixel. It defines how far the computation mask extends beyond the pupil mask. And, in fft, it is also the width of Neuman boundary where the derivative of the wavefront is set to zero.

maskScalingFactorLocalfloat

Mask scaling factor (for fast beam) for local correction.

Returns:

mask_pupilafwImage.Mask

Non-padded mask for use at the offset planes.

mask_compafwImage.Mask

Padded mask for use at the offset planes.