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High Res Modelling - Zbrush to Max workflow

This guidelines are for 3D Studio Max 2010 and Zbrush 4
I'm using Windows 7 64bit edition with 8gb or RAM



Zbrush mesh example
Sdiv 1 - 1245
Sdiv 7 - 5 million polys


Export mesh in Sdiv 2 to 3Ds max

I chose the subdivision that would allow for a really strong shillouete without any obvious untesellated edges.
I'm still not sure what is the ideal subdivision, in theory, Sdiv1 should give as good results as Sdiv2 but i still feel the edges aren't as strong as in ZBrush, ofcourse it could be because of the materials, but bottomline, the results are almost identical.


Generate Displacement Map from Sdiv 2 to Sdiv 7

Create a 16bit displacement map that matches the Sdiv level that was exported. Right now I'm using 4k maps (one for head and one for arms). 8k maps just kill the memory when rendering.
Don't forget to "Get Scale" and in some cases, like the "tshirt" do Smooth the UVs so you dont get hard edges when displacing.
Also I found that using "Adaptive" doesn't make any difference and sometimes gives some buggy results, and since it adds a lot of rendering time its not worth using it.


Generate Normal Map from Sdiv 6 to Sdiv 7

You get the displacement map and the normal map over the same details but the Normal map will help re-inforce the fine skin detail that gets lost in the resolution of the displacement map.
From the latest tests I cannot see any different worth the rendering time, you get a bit more sharpness but it isnt worth it.


3Ds Max

There are 2 ways to apply displacement maps, as a modifier or inside Mental Ray materials.
The big difference is that Mental Ray materials will subdivide your mesh bases on the pixel size of the final render while the displacement modifier will just subdivide your mesh in render time depending on how many subdivisions you want. From testing it out I found it really slows down renders and max runs out of memory much faster.


Mental Ray Displacement settings 
(you can see the Edge Length defining how much subdivision there will be per pixel)


So from these results I'll apply the displacement map in the displacement slot of the shader (in the output rollout, change RGB offset to -0.5.) and I usually match the strength that I got from Zbrush settings with the strength of the displacement.

The normal map is applied in the bump area of the shader. I've tried using the normal map as a straight bump OR applying a "Normal Bump" and placing the normal map there. The results with the "Normal bump" are much much smoother but, since the normal map is just giving that final pore or fabric details I'm not sure if its worth that extra rendering time. (In theory you should still use the "normal bump" if you are using a "normal map" to give you the correct results with the light.