From the Film Forum:
TwinK: People, can you ask? Why from the 4th episode (maybe not that episode, but where else Harrison Ford plays the role of Han Solo) So worsened the quality of the film? Sabers tremble, the effects are fig, the quality of the image is poor... In general, even Yoda has become some kind of plastic...
MiiYamoto San: Well, it was conceived, just Lucas wanted to show how everything was great under the Old Republic, and how all the shit became under the Empire.