The render settings I used for that picture was
Custom RenderWorks
Geometry - Curve Detail High, use Nurbs
Lighting - use shadows, ray traced shadows, transparent shadows, High quality
Ambient Light on 10% color black
Final Gather - Off
Rendering - Use Anti-Aliasing, Use Ray Tracing Max Refractions 32 Min. 3
Resolution 300 px/in
I found TIFF files do have a little better quality.