diff --git a/tracy/tracy/src/soleilcommon.cc b/tracy/tracy/src/soleilcommon.cc
index 9694cfbd5d3347314f1f6d383dbc95474b71fe7f..781f2408b60ba88ac2d2298711a0c894bb27b8ef 100644
--- a/tracy/tracy/src/soleilcommon.cc
+++ b/tracy/tracy/src/soleilcommon.cc
@@ -164,8 +164,9 @@ void Read_Lattice(char *fic)
     globval.bpm = ElemIndex("bpm");   /* get family index of bpm*/
     //globval.g = ElemIndex("g");  /* get family index of  girder*/
    
-   /* define x/y physical aperture  */
-    ChamberOff();
+   /* define x/y physical aperture, use the default values: +- 1 meter  */
+    globval.Aperture_on = false;
+    
     /* Compute and get Twiss parameters */
     Ring_GetTwiss(chroma = true, dP = 0.0);
 
@@ -207,7 +208,11 @@ void Read_Lattice(char *fic)
     globval.bpm = ElemIndex("bpm");   /* get family index of bpm*/
   //  globval.g = ElemIndex("g");  /* get family index of  girder*/
      
-    ChamberOff();
+    
+  /* define x/y physical aperture, use the default values: +- 1 meter  */
+    globval.Aperture_on = false;
+    
+    
     TransTwiss(alpha, beta, eta, etap, codvect);
     }
   }