Index: trunk/psModules/src/detrend/pmOverscan.c
===================================================================
--- trunk/psModules/src/detrend/pmOverscan.c	(revision 39499)
+++ trunk/psModules/src/detrend/pmOverscan.c	(revision 42338)
@@ -136,8 +136,12 @@
         break;
       case PM_FIT_SPLINE:
-        // XXX I don't think psSpline1D is up to scratch yet --- it has no mask, and requires an
-        // input spline
-        overscanOpts->spline = psVectorFitSpline1D(reduced, ordinate);
-        fitted = psSpline1DEvalVector(overscanOpts->spline, ordinate);
+
+        // XXX I don't think psSpline1D is up to scratch yet --- it has no mask, and it assumes
+	// a knot for every input point.  it needs an argument like 'number of knots' for the
+	// output spline.  EAM: still true 2023.01.22
+
+        // overscanOpts->spline = psVectorFitSpline1D(reduced, ordinate);
+        // fitted = psSpline1DEvalVector(overscanOpts->spline, ordinate);
+        psError(PS_ERR_UNKNOWN, true, "Spline overscan fitting is broken\n");
         break;
       default:
@@ -185,4 +189,5 @@
       }
       case PM_FIT_SPLINE: {
+	/*
 	  psSpline1D *spline = overscanOpts->spline; // The spline
 	  for (int i = 0; i < spline->n; i++) {
@@ -197,4 +202,5 @@
 	      comment = NULL;
 	  }
+	*/
 	  // write metadata header value
 	  psMetadataAddF32(hdu->header, PS_LIST_TAIL, "OVER_VAL", PS_META_REPLACE,