diff --git a/csst_mci_sim/csst_mci_sim.py b/csst_mci_sim/csst_mci_sim.py
index 3c5b2bcec612de2d0e420e75bd04f27833b6f628..cb825d738a4413ef0b24f82d088e253ce7767386 100644
--- a/csst_mci_sim/csst_mci_sim.py
+++ b/csst_mci_sim/csst_mci_sim.py
@@ -2250,8 +2250,14 @@ class MCIsimulator():
                                                         
                 stamp_img = galsim.Image(conv, copy=True)                        
                 stamp_img.setOrigin(0,0)                            
-                stamp_img.scale=0.025                             
-                self.log.info('load star catlog 999999999')
+                stamp_img.scale=0.025  
+                           
+                self.log.info('begining galsim.PhotonArray.makeFromImage')
+                
+                self.log.info('stamp_img.array.max()= %i' % (stamp_img.array.max()))
+                
+                print('stamp_img.array.max(): ', stamp_img.array.max() )
+                
                 #################################################   
                     
                 photons=galsim.PhotonArray.makeFromImage(stamp_img, max_flux=min(1.0, stamp_img.array.max()/10000.0))
@@ -2259,7 +2265,7 @@ class MCIsimulator():
                 cx0,cy0=centroid(stamp_img.array)
                 
                 
-                self.log.info('load star catlog 99999999999998')
+                self.log.info('galsim.PhotonArray.makeFromImage')
                 
                 if self.appFatt : 
                     
diff --git a/tests/test_mci_sim.py b/tests/test_mci_sim.py
index b03b1a83c4c7447cdef5f380dabc44057891f204..81afe25cc9190d0795feae7e35ad8f22c03583db 100644
--- a/tests/test_mci_sim.py
+++ b/tests/test_mci_sim.py
@@ -15,6 +15,9 @@ from csst_mci_sim import csst_mci_sim
 
 import sys
 
+
+import faulthandler
+
 class TestDemoFunction(unittest.TestCase):
     def test_mci_sim_1(self):
         
@@ -32,6 +35,8 @@ class TestDemoFunction(unittest.TestCase):
         The demo function returns the length of the input argument list.
         This case aims to test whether the demo function returns `1` if input is `None`.
         """
+        faulthandler.enable()
+        
         # demo function test
         dir_path = os.path.join(os.environ['UNIT_TEST_DATA_ROOT'],'mci_sim/')
         print(dir_path)