Problem with black artefats in normal map

Support Materials and Textures
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Hey Guys Hi!! I have this little problem with normals in my project, I saw this tutorial on youtube: (https://www.youtube.com/watch?v=s8N00rjil_4) to make this painterly effect in my character, i painted the normals and made the base painting and until this point everything was ok, but when I was going to put the normals in the character I had this black artefacts, I already tried to change the Tangent space to Object space in Normal map tab, but the artefact was even worse in some meshs, I don’t have much experience with shading (I am a concept and character artist trying making a short animation haha) so I am i little desperate to understand what is going on here because this job is for my finaltask super important in college and we have a short deadline.

Importantly: I’m using photoshop and substance to make the base colors and normal map painterly and add some fabric deformation to the normal map, like the seams of the clothes

image
image2573Ă—1039 390 KB

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Hi and welcome to BA.
First, thank you to let me discover that nice tutorials :grimacing:
About artifacts: have you checked if you have some wrong face orientation?

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3

First, figure out if the black artifacts are coming from your material:
temporarily: in Shader_Editor header, find name of material “rosto”,

  • click the Shield button to right of material name “rosto” (add a "fake user to this material so it won’t be accidentally deleted).
  • then click the “X” button to disconnect this material from your model.
  • next click [+ New] to add a new blank material.

Are the black artifacts still on model?
Yes: problem is with your model, not with material. (problem could be overlapping faces or objects, flipped normals, bad mesh …)
No: problem is with your original material “rosto”.

(Can now switch back to original material “rosto” – click “circle v” button next to material name in Shader_Editor header, for a list of all materials in .blend file. Pick “rosto”)

Second, figure out if the black is coming from your Base-Color image or from some problem with the Normal map input:
temporarily disconnect the noodle plugged into Principled_BSDF’s “Normal” input.
Are the black spots still there?
Yes: this means black is coming from your Base-Color image.
No: this means black is coming from Normal-Map image.

Third, make sure you are addressing the problem of the correct object. In the image you posted, you are working only on the head (head is outlined in orange, as currently selected object). UV unwrapped image only has room to cover head+face, not the entire body.
(Your Outliner (“editor” in upper right of entire Blender window) is currently set to “Blend File”, you usually want this set to “View Layers” so you can individually select objects, and or see which of all objects are currently selected. – In the Outliner_Editor, this can be changed with the dropdown menu 2nd-from left in header of Outliner.)
I’m talking about this, because most of the black artifacts (?) are on shirt, which is not the currently selected object – so all changes in world will not affect material of shirt right now. Skin color of character is vary dark, but not black, might be artifacts on face too, but hard to tell which you are concerned about.
You are not also showing us the Base-Color image, so it’s hard to say if skin color is what you painted, or if it is artifact.

I tried following the steps in the video, on a very simple round-beveled-cube, in blender 4.1.1, and I can assure you the steps work.
You have a very complex character model, with several separate parts.
Without being able to fully debug your current problem,
in the interests of time,
I recommend you try again, and to follow the steps in video closely.

Wish I could help you more.

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Hey Hi! Yes my face orientation are okay https://imgur.com/a/MCC5CM6

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Thank you so much for your effortful response, so, as it was my first post here I couldn’t post the other photos, but I had taken other images to demonstrate the difference in color in the viewport shader without normal (here: https://imgur.com/a/Gi4WcUB) and I also made a video to show what happens (here: https://imgur.com/a/tgSMxNP, ), normally this happens when I rotate the character or change the light. I think it has something to do with tangent space and object space too, about the YouTube video, something I noticed is that when the object has the metallic turned on 100% the object seems ok, which is what happens with the object of video he uses. in the video when I change it to tangent space it looks “ok”, but if I turn the character in another direction as I had done it continues with the artifacts, and yes I tested your recommendations and until then the problem is really in the normals, I can even record the video if you want to get an idea, and once again, thank you very much for the answer

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Making it in the same way or recreating the same problem may not be easy.
If you don’t mind, I think sharing even part of the problematic scene is the quickest way to determine the cause of this problem. :slightly_smiling_face:

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Thanks for the links to more images and the video.

further noodling around reveals that there is some bug in this process with Cycles in Particular.
I went back to the file I had worked on 20 hours ago, and now I too have black artifacts in Viewport_Shading = Rendered mode (for cycles),
but the artifacts disappear with Viewport_Shading = Material_Preview.

It’s not just the Viewport,
rendering the image now has black artifacts with Cycles, but not for Eevee. …but Eevee doesn’t even have the support to bake normal maps in the first place.

I believe you have uncovered some nasty bug in blender.
I bounced off the Bug_Reports, and thus far, I have not been able to locate anything resembling this behaviour.

:frowning:

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