I've found this great site which gives free model at http://3dup.com/index_eng.shtml. I found this rat so wonderful that I decided to do picture with him ! A small cat from Poser and a Big rat: who's who ???. Then I try to do fur for those two animals with this great tutorial at http://www.lynescreations.com/brycebump.htm. I've learned a lot with this render: how to import a hight resolution model in bryce, how to give it the good textures with the help of the Mat Lab, try to test the soft shadows and a way to find how we can see the shadows with the help of the Light Lab...