22"""Code to convert jointcal's output WCS models to distortion maps that can be
23used by afw CameraGeom.
31from lsst.geom import SpherePoint, Point2D, radians
37 """Convert a jointcal `~lsst.afw.geom.SkyWcs` into a distortion model and
40 Because this code only operates on the WCS, it is independent of the
41 format of the persisted output (e.g. gen2 separate files vs. gen3 bundled
47 The WCS to use to compute the distortion model
from, preferably
from
48 multiple visits on the same tract.
49 detectors : `list` [`int`]
50 Detector ids that correspond one-to-one
with ``wcsList``.
52 The camera these WCS were fit
for.
54 Number of points to compute the pixel scale at, along the +y axis.
56 def __init__(self, wcsList, detectors, camera, n=100):
74 self.
loglog = _LOG.getChild(
"CameraModel")
77 """Calculate the afw cameraGeom distortion model to be included in an
81 PLACEHOLDER: This may be as simple
as running `computePixelScale`
and
82 then doing a numpy polynomial fit to it
for the cameraGeom input.
83 However, we need to check details of how that distortion model
is
87 raise NotImplementedError(
"not yet!")
90 """Compute the radial and tangential pixel scale by averaging over
91 multiple jointcal WCS models.
93 Also computes the standard deviation and logs any WCS that are
95 The calculations are stored
in the ``fieldAngle[s]``,
96 ``radialScale[s]``,
and ``tangentialScale[s]`` member variables.
112 self.
loglog.warning(
"Large stddev in computed field angles between visits (max: %s degree).",
118 self.
loglog.warning(
"Large stddev in computed radial scales between visits (max: %s arcsec).",
123 self.
loglog.warning(
"Large stddev in computed tangential scales between visits (max: %s arcsec).",
127 """Compute the radial and tangential pixel scales using the distortion
128 model supplied with the camera.
130 This
is designed to be directly comparable
with the results of
131 `~CameraModel.computePixelScale`.
136 Detector identifier
for the detector_id to use
for the calculation.
140 fieldAngle : `numpy.ndarray`
141 Field angles
in degrees.
142 radialScale : `numpy.ndarray`
143 Radial direction pixel scales
in arcseconds/pixel.
144 tangentialScale : `numpy.ndarray`
145 Tangential direction pixel scales
in arcseconds/pixel.
150 iwcToSkyMap = iwcToSkyWcs.getFrameDict().getMapping(
"PIXELS",
"SKY")
151 skyFrame = iwcToSkyWcs.getFrameDict().getFrame(
"SKY")
154 pixSys = self.
cameracamera[detector_id].makeCameraSys(cameraGeom.PIXELS)
155 pixelsToFocal = self.
cameracamera.getTransform(pixSys, cameraGeom.FOCAL_PLANE)
156 focalToField = self.
cameracamera.getTransform(cameraGeom.FOCAL_PLANE, cameraGeom.FIELD_ANGLE)
159 pixelFrame =
ast.Frame(2,
"Domain=PIXELS")
160 focalFrame =
ast.Frame(2,
"Domain=FOCAL")
163 frameDict.addFrame(
"PIXELS", pixelsToFocal.getMapping(), focalFrame)
164 frameDict.addFrame(
"FOCAL", focalToField.getMapping(), iwcFrame)
165 frameDict.addFrame(
"IWC", iwcToSkyMap, skyFrame)
170 def _computeDetectorPixelScale(self, detector_id, wcs):
171 """Compute pixel scale in radial and tangential directions as a
172 function of field angle.
177 Detector identifier for the detector of this wcs.
179 Full focal-plane model to compute pixel scale on.
183 fieldAngle : `numpy.ndarray`
184 Field angles
in degrees.
185 radialScale : `numpy.ndarray`
186 Radial direction pixel scales
in arcseconds/pixel.
187 tangentialScale : `numpy.ndarray`
188 Tangential direction pixel scales
in arcseconds/pixel.
192 Pixel scales are calculated
from finite differences only along the +y
193 focal plane direction.
195 focalToSky = wcs.getFrameDict().getMapping('FOCAL',
'SKY')
196 mmPerPixel = self.
cameracamera[detector_id].getPixelSize()
198 focalToPixels = wcs.getFrameDict().getMapping(
'FOCAL',
'PIXELS')
199 trans = wcs.getTransform()
200 boresight = trans.applyForward(Point2D(focalToPixels.applyForward([0, 0])))
203 fieldAngle = np.zeros_like(rs)
204 radialScale = np.zeros_like(rs)
205 tangentialScale = np.zeros_like(rs)
206 for i, r
in enumerate(rs):
208 sp1 =
SpherePoint(*focalToSky.applyForward(Point2D([0, r])), radians)
210 sp2 =
SpherePoint(*focalToSky.applyForward(Point2D([0, r + mmPerPixel.getY()])), radians)
212 sp3 =
SpherePoint(*focalToSky.applyForward(Point2D([mmPerPixel.getX(), r])), radians)
213 fieldAngle[i] = boresight.separation(sp1).asDegrees()
214 radialScale[i] = sp1.separation(sp2).asArcseconds()
215 tangentialScale[i] = sp1.separation(sp3).asArcseconds()
216 return fieldAngle, radialScale, tangentialScale
def computeCameraPixelScale(self, detector_id=30)
def computePixelScale(self)
def computeDistortionModel(self)
def __init__(self, wcsList, detectors, camera, n=100)
def _computeDetectorPixelScale(self, detector_id, wcs)
static Log getLogger(std::string const &loggername)
std::shared_ptr< SkyWcs > makeSkyWcs(daf::base::PropertySet &metadata, bool strip=false)
Eigen::Matrix2d makeCdMatrix(lsst::geom::Angle const &scale, lsst::geom::Angle const &orientation=0 *lsst::geom::degrees, bool flipX=false)