to smooth the hills out you can:
apply a smooth modifier, (it may make the mesh VERY heacy though) could you chuck up a wire of the geometry so I can see how heavy it is?
Or you can increase the initial amount of faces in your mesh. Also there is a displacement setting initial samples is the one I am thinking of. Those might give better results..
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Alan
Ps. No crime fighting just work.... but that's with maya anyways and I'm the noob at work
Technical Director - Framestore
Currently working on: Your Highness
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