diff --git a/sch2fig/Makefile b/sch2fig/Makefile
index 67749e2..5116b64 100644
--- a/sch2fig/Makefile
+++ b/sch2fig/Makefile
@@ -34,7 +34,7 @@ test:		$(NAME)
 		./$(NAME) test.lib test.sch >out.fig
 		fig2dev -L png -m 2 out.fig _out.png
 		[ ! -r ref.png ] || \
-		    ! compare -metric AE ref.png _out.png _diff.png || \
+		    compare -metric AE ref.png _out.png _diff.png || \
 		    qiv -t -R -D _diff.png ref.png _out.png
 
 testref: