diff --git a/slicetimer.cc b/slicetimer.cc
index 232f665c263034b26c0ccd6f60b3b17e768a9509..98535e195836593ef9928194bbfc46a240b6987e 100644
--- a/slicetimer.cc
+++ b/slicetimer.cc
@@ -139,8 +139,8 @@ int do_slice_correction()
 	ColumnVector voxeltimeseries = timeseries.voxelts(x_pos,y_pos,slice-1);
 	ColumnVector interpseries = voxeltimeseries;
 	for (int time_step=1; time_step <= no_volumes; time_step++){
-	  // interpseries(time_step) = interpolate_1d(voxeltimeseries, time_step + offset + recenter);
-	  interpseries(time_step) = kernelinterpolation_1d(voxeltimeseries, time_step + offset + recenter, userkernel, 7);
+	  // interpseries(time_step) = interpolate_1d(voxeltimeseries, time_step - offset + recenter);
+	  interpseries(time_step) = kernelinterpolation_1d(voxeltimeseries, time_step - offset + recenter, userkernel, 7);
 	}
 	timeseries.setvoxelts(interpseries,x_pos,y_pos,slice-1);
       }