AstrometryTask: remove grow by maxOffsetPix

This grow is already performed by the reference catalog loader, but it
is controlled by the refObjLoader.pixelMargin parameter. That parameter
now matches maxOffsetPix. Added a note to maxOffsetPix that the pixelMargin
should be coordinated.

python/lsst/meas/astrom/astrometry.py

@@ -207,12 +207,9 @@ def solve(self, exposure, sourceCat):
         debug = lsstDebug.Info(__name__)
 
         expMd = self._getExposureMetadata(exposure)
-        exp_bbox = expMd.bbox
-        exp_bbox.grow(afwGeom.Extent2I(self.config.matcher.maxOffsetPix,
-                                       self.config.matcher.maxOffsetPix))
 
         loadRes = self.refObjLoader.loadPixelBox(
-            bbox=exp_bbox,
+            bbox=expMd.bbox,
             wcs=expMd.wcs,
             filterName=expMd.filterName,
             calib=expMd.calib,

python/lsst/meas/astrom/matchOptimisticB/matchOptimisticBContinued.py

@@ -67,7 +67,8 @@ class MatchOptimisticBConfig(pexConfig.Config):
         max=1,
     )
     maxOffsetPix = pexConfig.RangeField(
-        doc="Maximum allowed shift of WCS, due to matching (pixel)",
+        doc="Maximum allowed shift of WCS, due to matching (pixel). "
+            "When changing this value, the LoadReferenceObjectsConfig.pixelMargin should also be updated.",
         dtype=int,
         default=300,
         max=4000,

python/lsst/meas/astrom/matchPessimisticB.py

@@ -99,7 +99,8 @@ class MatchPessimisticBConfig(pexConfig.Config):
         min=1,
     )
     maxOffsetPix = pexConfig.RangeField(
-        doc="Maximum allowed shift of WCS, due to matching (pixel).",
+        doc="Maximum allowed shift of WCS, due to matching (pixel). "
+            "When changing this value, the LoadReferenceObjectsConfig.pixelMargin should also be updated.",
         dtype=int,
         default=300,
         max=4000,