def testCurvedFocalPlane(self):
"""Test a curved focal plane (with rectangular pixels)
"""
bbox = afwGeom.Box2I(afwGeom.Point2I(0, 0),
afwGeom.Extent2I(1000, 1000))
pixelSizeMm = afwGeom.Extent2D(0.02, 0.03)
plateScale = 25.0 # arcsec/mm
yaw = afwGeom.Angle(20, afwGeom.degrees)
fpPosition = afwGeom.Point2D(
50, 25) # focal-plane position of ref position on detector (mm)
refPoint = afwGeom.Point2D(
-0.5, -0.5) # ref position on detector (pos of lower left corner)
orientation = cameraGeom.Orientation(
fpPosition,
refPoint,
yaw,
)
plateScaleRad = afwGeom.Angle(plateScale,
afwGeom.arcseconds).asRadians()
focalPlaneToPupil = afwGeom.RadialXYTransform(
(0.0, plateScaleRad, 0.0, 0.001 * plateScaleRad))
pixelToTanPixel = makePixelToTanPixel(
bbox=bbox,
orientation=orientation,
focalPlaneToPupil=focalPlaneToPupil,
pixelSizeMm=pixelSizeMm,
plateScale=plateScale,
)
# the center point of the detector should not move
ctrPointPix = afwGeom.Box2D(bbox).getCenter()
ctrPointTanPix = pixelToTanPixel.forwardTransform(ctrPointPix)
for i in range(2):
self.assertAlmostEquals(ctrPointTanPix[i], ctrPointPix[i])
# two points separated by x pixels in tan pixels coordinates
# should be separated x * rad/tanPix in pupil coordinates,
# where rad/tanPix = plate scale in rad/MM * mean pixel size in mm
radPerTanPixel = plateScaleRad * (pixelSizeMm[0] +
pixelSizeMm[1]) / 2.0
pixelToFocalPlane = orientation.makePixelFpTransform(pixelSizeMm)
pixelToPupil = afwGeom.MultiXYTransform(
(pixelToFocalPlane, focalPlaneToPupil))
prevPointPupil = None
prevPointTanPix = None
for pointPix in (
afwGeom.Point2D(0, 0),
afwGeom.Point2D(1000, 2000),
afwGeom.Point2D(-100.5, 27.23),
afwGeom.Point2D(-95.3, 0.0),
):
pointPupil = pixelToPupil.forwardTransform(pointPix)
pointTanPix = pixelToTanPixel.forwardTransform(pointPix)
if prevPointPupil:
pupilSep = numpy.linalg.norm(pointPupil - prevPointPupil)
tanPixSep = numpy.linalg.norm(pointTanPix - prevPointTanPix)
self.assertAlmostEquals(tanPixSep * radPerTanPixel, pupilSep)
prevPointPupil = pointPupil
prevPointTanPix = pointTanPix
def testFlatFocalPlane(self):
"""Test an undistorted focal plane (with rectangular pixels)
"""
bbox = afwGeom.Box2I(afwGeom.Point2I(0, 0), afwGeom.Extent2I(1000, 1000))
pixelSizeMm = afwGeom.Extent2D(0.02, 0.03)
plateScale = 25.0 # arcsec/mm
yaw = afwGeom.Angle(20, afwGeom.degrees)
fpPosition = afwGeom.Point2D(50, 25) # focal-plane position of ref position on detector (mm)
refPoint = afwGeom.Point2D(-0.5, -0.5) # ref position on detector (pos of lower left corner)
orientation = cameraGeom.Orientation(
fpPosition,
refPoint,
yaw,
)
plateScaleRad = afwGeom.Angle(plateScale, afwGeom.arcseconds).asRadians()
focalPlaneToPupil = afwGeom.RadialXYTransform((0.0, plateScaleRad))
pixelToTanPixel = makePixelToTanPixel(
bbox=bbox,
orientation=orientation,
focalPlaneToPupil=focalPlaneToPupil,
pixelSizeMm=pixelSizeMm,
)
# with no distortion, this should be a unity transform
for pointPix in (
afwGeom.Point2D(0, 0),
afwGeom.Point2D(1000, 2000),
afwGeom.Point2D(-100.5, 27.23),
):
pointTanPix = pixelToTanPixel.forwardTransform(pointPix)
self.assertPairsNearlyEqual(pointTanPix, pointPix)
def testSimpleCurvedFocalPlane(self):
"""Test a trivial curved focal plane with square pixels
The CCD's lower left pixel is centered on the boresight
pupil center = focal plane center
CCD x is along focal plane x
"""
bbox = afwGeom.Box2I(afwGeom.Point2I(0, 0), afwGeom.Extent2I(1000, 1000))
pixelSizeMm = afwGeom.Extent2D(0.02, 0.02)
plateScale = 25.0 # arcsec/mm
yaw = 0 * afwGeom.degrees
fpPosition = afwGeom.Point2D(0, 0) # focal-plane position of ref position on detector (mm)
refPoint = afwGeom.Point2D(0, 0) # ref position on detector (pos of lower left corner)
orientation = cameraGeom.Orientation(
fpPosition,
refPoint,
yaw,
)
pixelToFocalPlane = orientation.makePixelFpTransform(pixelSizeMm)
plateScaleRad = afwGeom.Angle(plateScale, afwGeom.arcseconds).asRadians()
focalPlaneToPupil = afwGeom.RadialXYTransform((0.0, plateScaleRad, 0.0, 0.001 * plateScaleRad))
pixelToPupil = afwGeom.MultiXYTransform((pixelToFocalPlane, focalPlaneToPupil))
pixelToTanPixel = makePixelToTanPixel(
bbox=bbox,
orientation=orientation,
focalPlaneToPupil=focalPlaneToPupil,
pixelSizeMm=pixelSizeMm,
)
# pupil center should be pixel position 0, 0 and tan pixel position 0, 0
pixAtPupilCtr = pixelToPupil.reverseTransform(afwGeom.Point2D(0, 0))
self.assertPairsNearlyEqual(pixAtPupilCtr, [0, 0])
tanPixAtPupilCr = pixelToTanPixel.forwardTransform(pixAtPupilCtr)
self.assertPairsNearlyEqual(tanPixAtPupilCr, [0, 0])
# build same camera geometry transforms without optical distortion
focalPlaneToPupilNoDistortion = afwGeom.RadialXYTransform((0.0, plateScaleRad))
pixelToPupilNoDistortion = afwGeom.MultiXYTransform(
(pixelToFocalPlane, focalPlaneToPupilNoDistortion))
for x in (100, 200, 1000):
for y in (100, 500, 800):
pixPos = afwGeom.Point2D(x, y)
tanPixPos = pixelToTanPixel.forwardTransform(pixPos)
# pix to tan pix should be radial
self.assertAlmostEqual(
math.atan2(pixPos[1], pixPos[0]),
math.atan2(tanPixPos[1], tanPixPos[0]),
)
# for a given pupil angle (which, together with a pointing, gives a position on the sky):
# - pupil to pixels gives pixPos
# - undistorted pupil to pixels gives tanPixPos
pupilPos = pixelToPupil.forwardTransform(pixPos)
desTanPixPos = pixelToPupilNoDistortion.reverseTransform(pupilPos)
self.assertPairsNearlyEqual(desTanPixPos, tanPixPos)
def testCurvedFocalPlane(self):
"""Test a curved focal plane (with rectangular pixels)
"""
bbox = afwGeom.Box2I(afwGeom.Point2I(0, 0),
afwGeom.Extent2I(1000, 1000))
pixelSizeMm = afwGeom.Extent2D(0.02, 0.03)
plateScale = 25.0 # arcsec/mm
yaw = afwGeom.Angle(20, afwGeom.degrees)
# focal-plane position of ref position on detector (mm)
fpPosition = afwGeom.Point2D(50, 25)
# ref position on detector (pos of lower left corner)
refPoint = afwGeom.Point2D(-0.5, -0.5)
orientation = cameraGeom.Orientation(
fpPosition,
refPoint,
yaw,
)
pixelToFocalPlane = orientation.makePixelFpTransform(pixelSizeMm)
plateScaleRad = afwGeom.Angle(plateScale,
afwGeom.arcseconds).asRadians()
focalPlaneToField = afwGeom.makeRadialTransform(
(0.0, plateScaleRad, 0.0, 0.001 * plateScaleRad))
pixelToField = pixelToFocalPlane.then(focalPlaneToField)
pixelToTanPixel = makePixelToTanPixel(
bbox=bbox,
orientation=orientation,
focalPlaneToField=focalPlaneToField,
pixelSizeMm=pixelSizeMm,
)
# the center point of the field angle frame should not move
pixAtFieldCtr = pixelToField.applyInverse(afwGeom.Point2D(0, 0))
tanPixAtFieldCr = pixelToTanPixel.applyForward(pixAtFieldCtr)
self.assertPairsAlmostEqual(pixAtFieldCtr, tanPixAtFieldCr)
# build same camera geometry transforms without optical distortion
focalPlaneToFieldNoDistortion = afwGeom.makeRadialTransform(
(0.0, plateScaleRad))
pixelToFieldNoDistortion = pixelToFocalPlane.then(
focalPlaneToFieldNoDistortion)
for x in (100, 200, 1000):
for y in (100, 500, 800):
pixPos = afwGeom.Point2D(x, y)
tanPixPos = pixelToTanPixel.applyForward(pixPos)
# for a given field angle (which, together with a pointing, gives a position on the sky):
# - field angle to pixels gives pixPos
# - undistorted field angle to pixels gives tanPixPos
fieldPos = pixelToField.applyForward(pixPos)
desTanPixPos = pixelToFieldNoDistortion.applyInverse(fieldPos)
# use a degraded accuracy because small Jacobian errors accumulate this far from the center
self.assertPairsAlmostEqual(desTanPixPos,
tanPixPos,
maxDiff=1e-5)
def testCurvedFocalPlane(self):
"""Test a curved focal plane (with rectangular pixels)
"""
bbox = afwGeom.Box2I(afwGeom.Point2I(0,0), afwGeom.Extent2I(1000, 1000))
pixelSizeMm = afwGeom.Extent2D(0.02, 0.03)
plateScale = 25.0 # arcsec/mm
yaw = afwGeom.Angle(20, afwGeom.degrees)
fpPosition = afwGeom.Point2D(50, 25) # focal-plane position of ref position on detector (mm)
refPoint = afwGeom.Point2D(-0.5, -0.5) # ref position on detector (pos of lower left corner)
orientation = cameraGeom.Orientation(
fpPosition,
refPoint,
yaw,
)
plateScaleRad = afwGeom.Angle(plateScale, afwGeom.arcseconds).asRadians()
focalPlaneToPupil = afwGeom.RadialXYTransform((0.0, plateScaleRad, 0.0, 0.001 * plateScaleRad))
pixelToTanPixel = makePixelToTanPixel(
bbox = bbox,
orientation = orientation,
focalPlaneToPupil = focalPlaneToPupil,
pixelSizeMm = pixelSizeMm,
plateScale = plateScale,
)
# the center point of the detector should not move
ctrPointPix = afwGeom.Box2D(bbox).getCenter()
ctrPointTanPix = pixelToTanPixel.forwardTransform(ctrPointPix)
for i in range(2):
self.assertAlmostEquals(ctrPointTanPix[i], ctrPointPix[i])
# two points separated by x pixels in tan pixels coordinates
# should be separated x * rad/tanPix in pupil coordinates,
# where rad/tanPix = plate scale in rad/MM * mean pixel size in mm
radPerTanPixel = plateScaleRad * (pixelSizeMm[0] + pixelSizeMm[1]) / 2.0
pixelToFocalPlane = orientation.makePixelFpTransform(pixelSizeMm)
pixelToPupil = afwGeom.MultiXYTransform((pixelToFocalPlane, focalPlaneToPupil))
prevPointPupil = None
prevPointTanPix = None
for pointPix in (
afwGeom.Point2D(0, 0),
afwGeom.Point2D(1000, 2000),
afwGeom.Point2D(-100.5, 27.23),
afwGeom.Point2D(-95.3, 0.0),
):
pointPupil = pixelToPupil.forwardTransform(pointPix)
pointTanPix = pixelToTanPixel.forwardTransform(pointPix)
if prevPointPupil:
pupilSep = numpy.linalg.norm(pointPupil - prevPointPupil)
tanPixSep = numpy.linalg.norm(pointTanPix - prevPointTanPix)
self.assertAlmostEquals(tanPixSep * radPerTanPixel, pupilSep)
prevPointPupil = pointPupil
prevPointTanPix = pointTanPix
def testCurvedFocalPlane(self):
"""Test a curved focal plane (with rectangular pixels)
"""
bbox = afwGeom.Box2I(afwGeom.Point2I(0, 0), afwGeom.Extent2I(1000, 1000))
pixelSizeMm = afwGeom.Extent2D(0.02, 0.03)
plateScale = 25.0 # arcsec/mm
yaw = afwGeom.Angle(20, afwGeom.degrees)
fpPosition = afwGeom.Point2D(50, 25) # focal-plane position of ref position on detector (mm)
refPoint = afwGeom.Point2D(-0.5, -0.5) # ref position on detector (pos of lower left corner)
orientation = cameraGeom.Orientation(
fpPosition,
refPoint,
yaw,
)
pixelToFocalPlane = orientation.makePixelFpTransform(pixelSizeMm)
plateScaleRad = afwGeom.Angle(plateScale, afwGeom.arcseconds).asRadians()
focalPlaneToPupil = afwGeom.RadialXYTransform((0.0, plateScaleRad, 0.0, 0.001 * plateScaleRad))
pixelToPupil = afwGeom.MultiXYTransform((pixelToFocalPlane, focalPlaneToPupil))
pixelToTanPixel = makePixelToTanPixel(
bbox=bbox,
orientation=orientation,
focalPlaneToPupil=focalPlaneToPupil,
pixelSizeMm=pixelSizeMm,
)
# the center point of the pupil frame should not move
pixAtPupilCtr = pixelToPupil.reverseTransform(afwGeom.Point2D(0, 0))
tanPixAtPupilCr = pixelToTanPixel.forwardTransform(pixAtPupilCtr)
self.assertPairsNearlyEqual(pixAtPupilCtr, tanPixAtPupilCr)
# build same camera geometry transforms without optical distortion
focalPlaneToPupilNoDistortion = afwGeom.RadialXYTransform((0.0, plateScaleRad))
pixelToPupilNoDistortion = afwGeom.MultiXYTransform(
(pixelToFocalPlane, focalPlaneToPupilNoDistortion))
for x in (100, 200, 1000):
for y in (100, 500, 800):
pixPos = afwGeom.Point2D(x, y)
tanPixPos = pixelToTanPixel.forwardTransform(pixPos)
# for a given pupil position (which, together with a pointing, gives a position on the sky):
# - pupil to pixels gives pixPos
# - undistorted pupil to pixels gives tanPixPos
pupilPos = pixelToPupil.forwardTransform(pixPos)
desTanPixPos = pixelToPupilNoDistortion.reverseTransform(pupilPos)
self.assertPairsNearlyEqual(desTanPixPos, tanPixPos)
def testFlatFocalPlane(self):
"""Test an undistorted focal plane (with rectangular pixels)
"""
bbox = afwGeom.Box2I(afwGeom.Point2I(0, 0),
afwGeom.Extent2I(1000, 1000))
pixSizeFactor = numpy.array((1.2, 0.8))
pixelSizeMm = afwGeom.Extent2D(0.02 * pixSizeFactor[0],
0.02 * pixSizeFactor[1])
plateScale = 25.0 # arcsec/mm
yaw = afwGeom.Angle(20, afwGeom.degrees)
fpPosition = afwGeom.Point2D(
50, 25) # focal-plane position of ref position on detector (mm)
refPoint = afwGeom.Point2D(
-0.5, -0.5) # ref position on detector (pos of lower left corner)
orientation = cameraGeom.Orientation(
fpPosition,
refPoint,
yaw,
)
plateScaleRad = afwGeom.Angle(plateScale,
afwGeom.arcseconds).asRadians()
focalPlaneToPupil = afwGeom.RadialXYTransform((0.0, plateScaleRad))
pixelToTanPixel = makePixelToTanPixel(
bbox=bbox,
orientation=orientation,
focalPlaneToPupil=focalPlaneToPupil,
pixelSizeMm=pixelSizeMm,
plateScale=plateScale,
)
# with no distortion, this should be a unity transform
ctrPointPix = numpy.array(afwGeom.Box2D(bbox).getCenter())
for pointPix in (
afwGeom.Point2D(0, 0),
afwGeom.Point2D(1000, 2000),
afwGeom.Point2D(-100.5, 27.23),
):
pointTanPix = pixelToTanPixel.forwardTransform(pointPix)
predPointTanPix = ((numpy.array(pointPix) - ctrPointPix) *
pixSizeFactor) + ctrPointPix
for i in range(2):
self.assertAlmostEquals(pointTanPix[i], predPointTanPix[i])
def testFlatFocalPlane(self):
"""Test an undistorted focal plane (with rectangular pixels)
"""
bbox = afwGeom.Box2I(afwGeom.Point2I(0,0), afwGeom.Extent2I(1000, 1000))
pixSizeFactor = numpy.array((1.2, 0.8))
pixelSizeMm = afwGeom.Extent2D(0.02 * pixSizeFactor[0], 0.02 * pixSizeFactor[1])
plateScale = 25.0 # arcsec/mm
yaw = afwGeom.Angle(20, afwGeom.degrees)
fpPosition = afwGeom.Point2D(50, 25) # focal-plane position of ref position on detector (mm)
refPoint = afwGeom.Point2D(-0.5, -0.5) # ref position on detector (pos of lower left corner)
orientation = cameraGeom.Orientation(
fpPosition,
refPoint,
yaw,
)
plateScaleRad = afwGeom.Angle(plateScale, afwGeom.arcseconds).asRadians()
focalPlaneToPupil = afwGeom.RadialXYTransform((0.0, plateScaleRad))
pixelToTanPixel = makePixelToTanPixel(
bbox = bbox,
orientation = orientation,
focalPlaneToPupil = focalPlaneToPupil,
pixelSizeMm = pixelSizeMm,
plateScale = plateScale,
)
# with no distortion, this should be a unity transform
ctrPointPix = numpy.array(afwGeom.Box2D(bbox).getCenter())
for pointPix in (
afwGeom.Point2D(0, 0),
afwGeom.Point2D(1000, 2000),
afwGeom.Point2D(-100.5, 27.23),
):
pointTanPix = pixelToTanPixel.forwardTransform(pointPix)
predPointTanPix = ((numpy.array(pointPix) - ctrPointPix) * pixSizeFactor) + ctrPointPix
for i in range(2):
self.assertAlmostEquals(pointTanPix[i], predPointTanPix[i])
def testSimpleCurvedFocalPlane(self):
"""Test a trivial curved focal plane with square pixels
The CCD's lower left pixel is centered on the boresight
pupil center = focal plane center
CCD x is along focal plane x
"""
bbox = lsst.geom.Box2I(lsst.geom.Point2I(0, 0),
lsst.geom.Extent2I(1000, 1000))
pixelSizeMm = lsst.geom.Extent2D(0.02, 0.02)
plateScale = 25.0 # arcsec/mm
yaw = 0 * lsst.geom.degrees
# focal-plane position of ref position on detector (mm)
fpPosition = lsst.geom.Point2D(0, 0)
# ref position on detector (pos of lower left corner)
refPoint = lsst.geom.Point2D(0, 0)
orientation = cameraGeom.Orientation(
fpPosition,
refPoint,
yaw,
)
pixelToFocalPlane = orientation.makePixelFpTransform(pixelSizeMm)
plateScaleRad = lsst.geom.Angle( # rad/mm
plateScale, lsst.geom.arcseconds).asRadians()
focalPlaneToField = afwGeom.makeRadialTransform(
(0.0, plateScaleRad, 0.0, 0.001 * plateScaleRad))
pixelToField = pixelToFocalPlane.then(focalPlaneToField)
pixelToTanPixel = makePixelToTanPixel(
bbox=bbox,
orientation=orientation,
focalPlaneToField=focalPlaneToField,
pixelSizeMm=pixelSizeMm,
)
# field center should be pixel position 0, 0 and tan pixel position 0,
# 0
pixAtFieldCtr = pixelToField.applyInverse(lsst.geom.Point2D(0, 0))
self.assertPairsAlmostEqual(pixAtFieldCtr, [0, 0])
tanPixAtFieldCr = pixelToTanPixel.applyForward(pixAtFieldCtr)
self.assertPairsAlmostEqual(tanPixAtFieldCr, [0, 0])
# build same camera geometry transforms without optical distortion
focalPlaneToFieldNoDistortion = afwGeom.makeRadialTransform(
(0.0, plateScaleRad))
pixelToFieldNoDistortion = pixelToFocalPlane.then(focalPlaneToFieldNoDistortion)
for x in (100, 200, 1000):
for y in (100, 500, 800):
pixPos = lsst.geom.Point2D(x, y)
tanPixPos = pixelToTanPixel.applyForward(pixPos)
# pix to tan pix should be radial
self.assertAlmostEqual(
math.atan2(pixPos[1], pixPos[0]),
math.atan2(tanPixPos[1], tanPixPos[0]),
)
# for a given field angle (which, together with a pointing, gives a position on the sky):
# - field angle to pixels gives pixPos
# - undistorted field anle to pixels gives tanPixPos
fieldPos = pixelToField.applyForward(pixPos)
desTanPixPos = pixelToFieldNoDistortion.applyInverse(
fieldPos)
self.assertPairsAlmostEqual(desTanPixPos, tanPixPos)
