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Normal texture is OK
Diffuse texture is terrible =(
How to fix it?
I am not sure if that is the problem, but you are plugging a color managed RGB texture into a normal vector socket. That’s sacrilege! Please change ‘Color’ to ‘Non-Color Data’ in the Image Texture node, and plug it to Normal Map node before sticking it to Normal input of Diffuse BSDF. That might fix it if you are baking diffuse while the normal map is incorrectly used. Is there a reason you are using normal map for diffuse and not for glossy?
Everything martin states, and also you usually plug the normal output into all (or most) bsdf normal slots. Looks like this:
bump is the same, but instead of vector,normal map you use, vector, bump map
You know I don’t need to plug any sockets in to bake it, it’s just a repeated bug.
I need to connect sockets to use maps only in render not to bake it.
Of course you do. The material must be properly setup otherwise there is nothing to bake !