The low level base model that we created.
Window->Rendering Editors->Mental Ray-Approximation Editor->Create Subdivison
There are a few settings to play with, If using Parametric, Match the N subdivisions to the number of divisions we sculpted to. The lower the number, the quicker the render, the less resolution you end up with. When using Spacial, length needs to be adjusted until the proper results are rendered.
This displacement was baked for major forms only, there is no high resolution detail here. Notice the silhouette change. The color balance of the displacement file node needs to be adjusted. Specifically, Alpha Gain and Alpha Offset. You are adjusting the max and min displacement of the mesh with these values. Typical result of Alpha Offset = -Alpha Gain/2 ....... I.E. Alpha gain .1, Alpha Offset -.05
We capture the high res using a normal or a bump map, and apply that on top of the displacement. This yields a quicker render time when the object does not need to be viewed closely
This is a pure Displacement map, It takes longer to render because the mesh needs to be subdivided a greater number of times to capture the bump detail from the last slide. The end result is comparable. This is sometimes needed for close ups as it is actually displacing the high res detail rather than faking it like the last slide.
