Need Help: Weird Normal Map After Baking with Normal Map in Retopo Room

[tat2charmander]

Help needed!
I used Bake with Normal Map in the Retopo Room, but after the baking process finished, I noticed in the Painting Room that the resulting normal map is completely broken. Additionally, after running Calculate Occlusion, some parts of the model turned black.

I’m not sure whether this issue is caused by problems with the model itself, or if I made mistakes during certain steps of the workflow.

The high-poly model was fully sculpted in 3DCoat. The low-poly model was generated by exporting the high-poly mesh to another software for automatic retopology, then slightly edited in Blender, and finally re-imported back into 3DCoat. I initially tried using 3DCoat’s built-in AutoPO, but the topology quality was not satisfactory, which is why I switched to a different retopology solution.

Before this bake, I had already successfully used Bake with Normal Map on two other models without any issues. This problem only occurred on the third model.

Because my .3b file is too large to upload, I will instead provide relevant screenshots to help illustrate the issue.

[Carlosan]

This model is very tiny ?

May be inner and outer cage (on Bake settings) are collapsing ?

[tat2charmander]

2026年1月8日下午7点45分，卡洛桑说：

这个模型非常紧凑？

可能是外笼（在烘焙设置中）床垫陷了？

感谢您的回复。
我后来尝试了一些其他方法，看来问题可能与烘焙多个网格有关。

每当我尝试烘焙第三个网格时，问题就会出现在这个网格上。但是，如果我删除前两个已经烘焙好的网格，第三个网格就可以正常烘焙，没有任何问题。

Edited Friday at 12:51 PM by tat2charmander

[Carlosan]

The model have uDims ?

If yes, try this workflow

 

[tat2charmander]

On 1/9/2026 at 9:15 PM, Carlosan said:

The model have uDims ?

If yes, try this workflow

 

Although I’m not very familiar with UDIMs, after watching the video, I believe my bake should be using UDIMs, since I rename the mesh each time before baking.
I’ll try the method shown in the video next and see if the issue still occurs.
Thank you for your reply.

[Carlosan]

UDIM (U Dimension) is a texture mapping workflow that spreads a single high-resolution UV map across multiple image tiles, allowing for extremely detailed textures on complex 3D models without using one massive, impractical file, commonly used in VFX and animation.

It works by organizing UVs into a grid of "tiles" (e.g., 1001, 1002, etc.), each holding a separate texture file, and is supported by many 3D software.