Update calcZernikes with depreacation of config and more documentatio…

…n on coord. transform.
lsst-ts · Oct 12, 2023 · 59c316a · 59c316a
1 parent 7d67487
commit 59c316a
Showing 1 changed file with 26 additions and 2 deletions.
diff --git a/python/lsst/ts/wep/task/calcZernikesTask.py b/python/lsst/ts/wep/task/calcZernikesTask.py
@@ -109,6 +109,14 @@ class CalcZernikesTaskConfig(
     instPixelSize = pexConfig.Field(
         doc="Instrument Pixel Size in m", dtype=float, default=10.0e-6
     )
+    transposeImages = pexConfig.Field(
+        doc="Specify whether to transpose the intra- and extra-focal images. \
+        (The default is to do the transpose).",
+        dtype=bool,
+        default=True,
+        optional=True,
+        deprecated="This field is no longer used. Will be removed after the end of October 2023."
+    )
 
 
 class CalcZernikesTask(pipeBase.PipelineTask):
@@ -227,9 +235,25 @@ def estimateZernikes(self, donutStampsExtra, donutStampsIntra):
             blendOffsetsExtra = self.calcBlendOffsets(donutExtra, eulerZExtra)
             blendOffsetsIntra = self.calcBlendOffsets(donutIntra, eulerZIntra)
 
-            # Transform image and coordinates from DVCS
+            # Below we transform the image array and coordinates from the DVCS
             # (Data Visualization Coordinate System)
-            # to ZCS (Zemax Coordinate System).
+            # to the ZCS (Zemax Coordinate System). More information about these
+            # coordinate systems is available here: sitcomtn-003.lsst.io.
+            # This transformation below incorporates two different coordinate
+            # conversions: 1) DVCS to CCS is a transpose and 2) CCS to ZCS is
+            # an x -> -x conversion that we can incorporate as a left-right flip.
+            # In a future update to ts_ofc we will update the sensitivity matrix
+            # to use the CCS and we can then remove the left-right flip. That is
+            # why the current version keeps this as a two-part transformation.
+            #
+            #        DVCS               CCS                 ZCS
+            #   x                   y                               y
+            #   ^                   ^                               ^
+            #   |                   |                               |
+            #   |                   |                               |
+            #   |                   |                               |
+            #   |----------> y      |----------> x     x <----------|
+
             wfEsti.setImg(
                 np.array([-fieldXYExtra[1], fieldXYExtra[0]]),
                 DefocalType.Extra,