After the precious advice from Tor Frick the columns is from now made of 9818 triangles (instead of 50 000 about ^^,) and its shape is not that much changed :D Whatch it in 3D with Verold:: http://goo.gl/aT3EOB
Thx! ;) For the wood's texture, I have baked a normal and an occlusion from the Zbrush sculpt, where I have apply wooden alpha (from picture) on it and I have used the trimdynamic brush to give more variations for the edges. Then I have blended severals wood's textures in Photoshop using mask here and there to get a good…