diff --git a/Catalog/C6_50sqdeg.py b/Catalog/C6_50sqdeg.py
index 0c6d22b9deaf9a934ca23c4c6ad008ce0f44c00d..f13faa7f2df61a4205e49ef6d0def8301ef196a3 100644
--- a/Catalog/C6_50sqdeg.py
+++ b/Catalog/C6_50sqdeg.py
@@ -6,7 +6,6 @@ import h5py as h5
 import healpy as hp
 import astropy.constants as cons
 import traceback
-import cmath
 from astropy.coordinates import spherical_to_cartesian
 from astropy.table import Table
 from scipy import interpolate
@@ -222,13 +221,17 @@ class Catalog(CatalogBase):
             param['e2'] = gals['ellipticity_true'][igals][1]
             
             # For shape calculation
-            
-            param['ell_total'] = np.sqrt(param['e1']**2 + param['e2']**2)
+            param['e1'], param['e2'], param['ell_total'] = self.rotate_ellipticity(
+                                                                    e1=gals['ellipticity_true'][igals][0],
+                                                                    e2=gals['ellipticity_true'][igals][1],
+                                                                    rotation=self.rotation,
+                                                                    unit='radians')
+            # param['ell_total'] = np.sqrt(param['e1']**2 + param['e2']**2)
             if param['ell_total'] > 0.9:
                 continue
-            phi_e = cmath.phase(complex(param['e1'], param['e2']))
-            param['e1'] = param['ell_total'] * np.cos(phi_e + 2*self.rotation)
-            param['e2'] = param['ell_total'] * np.sin(phi_e + 2*self.rotation)
+            # phi_e = cmath.phase(complex(param['e1'], param['e2']))
+            # param['e1'] = param['ell_total'] * np.cos(phi_e + 2*self.rotation)
+            # param['e2'] = param['ell_total'] * np.sin(phi_e + 2*self.rotation)
             
             param['e1_disk'] = param['e1']
             param['e2_disk'] = param['e2']
diff --git a/ObservationSim/MockObject/CatalogBase.py b/ObservationSim/MockObject/CatalogBase.py
index a21edbaf4e8dd561ba28cd71cdbdfced98602eab..a5e7e6b84e2cb4a6970b6f0af01c4aad8884b386 100644
--- a/ObservationSim/MockObject/CatalogBase.py
+++ b/ObservationSim/MockObject/CatalogBase.py
@@ -1,6 +1,7 @@
 import numpy as np
 import galsim
 import copy
+import cmath
 
 from astropy.table import Table
 from abc import abstractmethod, ABCMeta
@@ -72,6 +73,16 @@ class CatalogBase(metaclass=ABCMeta):
             "parallax":1e-9
         }
         return param
+
+    @staticmethod
+    def rotate_ellipticity(e1, e2, rotation=0., unit='radians'):
+        if unit == 'degree':
+            rotation = np.radians(rotation)
+        e_total = np.sqrt(e1**2 + e2**2)
+        phi = cmath.phase(complex(e1, e2))
+        e1 = e_total * np.cos(phi + 2*rotation)
+        e2 = e_total * np.sin(phi + 2*rotation)
+        return e1, e2, e_total
     
     @staticmethod
     def convert_sed(mag, sed, target_filt, norm_filt=None):