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I'm trying to add some wrinkles to these pants by baking a high poly sculpt into a normal map but i get these weird artifacts in my normal map. I'm not sure what I'm doing wrong that would be causing this. I've restarted from the same low poly model multiple times with different sculpts and different bakes and I always get the same artifacts. Any help would be appreciated.enter image description here

For some reason there is this weird smooth looking section on the inseam and I'm not sure where it's coming from. Here's a picture of the high poly sculpt and there is no visible issue with the sculpt itself. enter image description here

As a side not that is not as serious of an issue there seems to be an unusual discoloration between the seams of the mesh despite me just using a flat color as the base input color. I've included my node setup in case that might help. enter image description here

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  • $\begingroup$ Hello, please share your file so that we can give a try: blend-exchange.giantcowfilms.com $\endgroup$
    – moonboots
    Commented Aug 31, 2020 at 6:33
  • $\begingroup$ First of all, normal map should be set to Non-Color (in general, all maps except for albedo should be, but normals in particular). There will always be discoloration in the normal map on the seams, that's how tangent space is working $\endgroup$
    – Mr Zak
    Commented Aug 31, 2020 at 11:24

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This is a rather common issue with this technique. what is happening: In order to understand how "bumpy" something with completely different geometry is, blender uses a "third model" called a "cage". (when it's unchecked, the cage just uses the selected model to make it, with the solidify modifier I presume) the cage shoots rays from itself to both the low and high poly geometry, and compares them both to itself. This is a rudimentary technique though, and fails in some specific cases: notably in acute angles when the cage passes through some geometry that's closer to it than the intended geometry. in a visual sense, this is a simplification, where the blue line is the cage. enter image description here (in reality, there's no extra face at the top, or if there is, there's some more geometry smoothing it out a little, and probably extending your issue down the legs a bit because of how the cage contracts at sharp, concave corners!)

notice how parts of the cage will see the "backside" of the model first. Basically, you want the cage to be as small as possible while still providing good results. shrink that .3 to half or less, unless the distance between the sculpted and low poly geometry differ that much- and at that point you should probably consider shrink wrapping the lowpoly to fit the high poly geometry more closely. normals are for making glancing and stark shadows better, not replacing proper geometric shapes big enough to add very noticeable bumps to a silhouette.

use the measurement tool and draw a .3m line on the pants, and visualize how big that cage is- that should assist you in finding the right cage size!

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  • $\begingroup$ Oh this makes so much sense! I shrunk it down to .02 and it looks perfect now! Thank you so much! $\endgroup$
    – Joe Matt
    Commented Aug 31, 2020 at 13:35
  • $\begingroup$ yepyep. everyone comes across it eventually. pass it on when you can- though with any luck the new multires modifier changes should make this a nonissue! $\endgroup$
    – Nubnubbud
    Commented Sep 1, 2020 at 5:31

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