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Problem when baking a Normal map in Zbrush

polycounter lvl 9
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Mik2121 polycounter lvl 9
Yesterday I started to make a new prop for some school project and got some issues when I tried to bake the Normal Map from Zbrush.
This is the object I'm trying to create (with a Concept Sketch here):

21oc2zt.jpg
This is the 'complete' model.


1z48x39.jpg
This is the part I made for the UV so I could just copy the other half and one of the 'legs' and save space on my texture.

2wnb585.jpg
This is the UV layout.

Now here is where the problems begin... after exporting it to Zbrush.

2lka5ir.jpg
This is the sculpted model. It has 8 subdivisions so I could keep the very few details as sharp as possible.

nqqnw4.jpg
And this is the result when I bake the Normal Map. I'm using Zbrush 3.1 and in the Normal Map area, when I check Smooth UV it will just mess up my normal so badly. I also tried turning Adaptive on, but the only thing it made was take up 50 minutes of my free time to give me the same results as with Tangent on, but with the colors... inverted? (it was all purple and green).

Now this one has a few problems like the circles on the bottom left area, and you can see some sort of gradient going on in the legs, when I didn't make anything around there. I guess I can just go with Photoshop and clear up all those areas, but still.. I wonder if there's any way to bake better Normal Maps from Zbrush?

Also, when you get a Normal that has greens and purples around, can it be used easily? Is there some way to turn that into the typical blue-ish normal? I believe some time ago I made it maybe with the trial of Crazy Bump, but I'm not really sure..

Anyway, what I basically want to ask, again, is... Is there any way to bake better Normals that have no errors like the circles in my current normal? Or maybe there's something wrong with my workflow or the model mesh?.

I plan on using it with the UDK and the model has around 1100 polygons.

Replies

  •  Chris Bruin
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    Chris Bruin polycounter lvl 10
    Do you have any images of the level 8 sculpt?

    All I use when baking normals (in R3) is Tangent, not Adaptive or Smooth. You are using R3, right?

    If the normal colors are inverted, you can invert them in Photoshop. (Crtl+I)
  • Mik2121
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    Mik2121 polycounter lvl 9
    As sad as it sounds, the picture I posted there is the model at subdivision level 8. I remade it to post it here and kept it simple because I already knew the details wouldn't translate correctly and I might need to fix something from the model, or something. I want to make a much more detailed version, but I fear I might not be able to use all those details because of something wrong with the mesh or something. If you need wireframes of the 3DSMax model, just ask. But I'd guess it's fairly simple.

    And yeah, I'm using Tangent as well for the normal map I baked, but as I said, it leaves some areas that really need lots of fixes. I'm using Zbrush 3.1, it's not the 3.5 R3, if that's what you're asking.

    And the normals didn't look like they could just be inverted with Photoshop. They had a lot of colors, including a bit of blue, so if I inverted I would still get 'wrong' colors in some places.

    Thanks for the help.
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