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I've been strugling for a few days now, trying to find answers/causes of this. Unfortunately without luck.. So now I'm seeking help.

Issue: Excessive loss of detail when baking normals from High Poly to Low Poly mesh

Blender proficiency: Beginner

Details: When baking a High Poly mesh unto a Low Poly mesh significant details are lost on the normal map, and quality is generally bad - despite me trying bake resolutions up to 16k.

High Poly Mesh: Notice the amount of "fine" details along the rim of the ring. These are not transfered to the baked normal map. Notice the amount of "fine" details along the rim of the ring.

When I bake from the High Poly Mesh, unto a Low Poly mesh (with same center) using a Cage mesh, the resulting Normal Map looks like this. I can't seem to figure out how to improve this.. Been fiddling with a bunch of things trying to improve it. Smooth shading, Flat shading, different shaders, render samples, Pixel margin, tangent vs object space, bevels, weighted normals etc. with no luck.. enter image description here If we look a bit closer at the generated normal map, these areas are what raises my concern, as the high poly details in some parts carry over, but in most parts simply "disappear".. enter image description here

Anyone experience anything similar, and know what I'm not doing right? Below is my setup in blender, all meshes are centered in the same origin. The Low Poly mesh is basically the same size as the high poly (just less detailed) and the cage is scaled to just exactly enclose the entire high poly model:

enter image description here

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    $\begingroup$ if the faces are completely perpendicular to the rays, they won't be baked, maybe it's the case here? $\endgroup$
    – moonboots
    Aug 18 at 19:45
  • $\begingroup$ Thank you for the advise! Did not consider that this could be an issue. Will look into it some more based on above, and see if I can "fix" it! $\endgroup$
    – Kris
    Aug 18 at 20:02
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    $\begingroup$ I meant perpendicular and parallel of course ;) I hope you've fixed your problem $\endgroup$
    – moonboots
    Aug 19 at 18:55
  • $\begingroup$ Your advise was spot on! Some quick testing with more "sloped" angles did indeed make a difference. However I've not yet been able to actually fix the entire mesh (simply haven't had the time yet). Will post a proper answer here, once I finally get it fixed as I intend :) $\endgroup$
    – Kris
    Aug 19 at 20:55
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Answer: Based on Moonboot's comment about the rays hitting the mesh either directly perpendicular or parallel, I did some testing to see if changing the "direction of attack" for the rays, would improve the baked normal map.

Even though this is a hard-surface mesh I am modelling, I decided to add small bevels along all affected edges.

Basically I selected all the relevant edges. Pressed CTRL-B, and added a bevel edge!

Basically I went from this: enter image description here

to this: enter image description here

The effect on the Normal map is significant. Before the "details" were barely visible: enter image description here

And this is how it looks with such a "simple" edit (adding the bevels): enter image description here

It's not perfect yet. Nor am i finished! But at least this hurdle has been defeated! Now I can continue working on the other details, UV layout, etc!

Thank you for the help!

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