Intinerary 3 weeks for off beaten path

My wife and I will be going to Japan for about 3 weeks from May 7 to May 26, 2008. I am a photographer and my wife an artist. Would like some suggestion on places to visit that off the ''beaten path'' and that are accessible via train which will be our main transport. We arrive and leave via Tokyo. This is our second trip to Japan where we have visited Tokyo and Kyoto. Thanks for your help.
Jim

Without knowing your specific interests, I can only make general recommendations.

You could actually spend months traveling, off the beaten path in Japan, for there is quite a bit to see. Yet, with a JR Rail Pass, and by taking advantage of the shinkansen (bullet train), you could cover a lot of ground, and could make it is far as Kagoshima in Kyushu.

Overall, the Japan Sea side of Japan, Shikoku, and Kyushu are underrated travel destinations that get few foreign visitors, but tend to be some of my favorite destinations. Also consider a trip to an outlying island like Sado near Niigata, or Amami or the even the Ryukyu islands.