View Full Version : Displacement bloating from ZBrush?

12 December 2006, 12:23 PM
Hi All,

Just testing Zbrush to Maya displacements and noticed an overall bloating in the render.

I only displaced the eye, chin and forehead area - yet the whole head and ear bloats.

Any ideas what is causing this and how to solve it?

Many Thanks,

12 December 2006, 04:02 PM
Sometimes Zbrush produces displacement maps where neutral areas aren't quite 50% gray--so, you need to redo the displacement map or take it into photoshop and change the levels until your neutral area is 50% gray. :)

I'm more of a Mudbox kind of guy, but I had used Zbrush and ran into that problem exactly.

Edit: Just to clarify, when I say "redo the displacement map" I don't mean re-make it; Just redo the steps you took in extracting it from your Zbrush file--or take it into photoshop...pop a 50% gray blotch on a new layer above the neutral area and color match on a pixel-sized level. Either way, you need youe neutral areas to be 50% gray.

12 December 2006, 01:14 AM
I think you can just set the alpha offset to -0.5 in Maya, or something like that...

12 December 2006, 10:18 AM
Yes ytou can write an expression to so that it will always be negative half of the alpha gain, using those settings and modifying a bit also kinda varies in result. I am not sure on what this depends the level of detail or scale of you scene perhaps ?

12 December 2006, 03:17 PM
Yep, its gamma and offset controls you need to fiddle with. The most reliable way is detailed in the 'maya pipeline' pdf file available here
(using multi displacement 2 select the R32 option and enter the DE-LBEK-EAEAEA-R32)

You also have to make sure you're using the latest displacment exporter (download from pixologic download centre). IIRC if you use the settings for the plugin detailed in the pdf file and set alpha gain to 2.2 and offset -1.1 all goes fine.

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12 December 2006, 03:17 PM
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