We report V , R , and I band CCD photometry of the radio galaxy 3C 390.3 obtained with the 1.56-m telescope of the Shanghai Astronomical Observatory from March 1995 to August 2004 .
Combining these data with data from the literature , we have constructed a historical light curve from 1894 to 2004 and searched for periodicities using the CLEANest program .
We find possible periods of 8.30 \pm 1.17 , 5.37 \pm 0.49 , 3.51 \pm 0.21 , and 2.13 \pm 0.08 years .