Change shift orientation

maoppy/psfmodel.py

@@ -508,7 +508,7 @@ class Psfao(ParametricPSF):
         else:
             dlFTO = 1.
         X, Y = self._shift_array(self.Npix[0]*self._k,self.Npix[1]*self._k)
-        return np.exp(-Dphi/2.)*dlFTO*np.exp(X*dx*self._k + Y*dy*self._k)
+        return np.exp(-Dphi/2.)*dlFTO*np.exp(-X*dx*self._k - Y*dy*self._k)
     
     def __call__(self,x0,dx=0,dy=0):
         """