Wavy shading on normal maps when changing roughness value

dasilvardas

Hi,

I hope everyone is fine, I have been learning to use SP to bake normal maps from  high poly to low poly meshes, I thought I was doing the process right, since my normal maps seem to be fine after baking, however when I increase the roughness, what I think is the normal map starts showing shading artifacts, some kind of Waviness becomes very noticeable, I am more than happy to attach images showing what happens here.

Here is my mesh with a roughness value of about 0.5


This is what happens when the roughness is near to 0.0


I think it is also important to share the normal map generated after baking
UVs

And here is the object displaying soft and hard edges (soft are the dotted line and hard the regular line)


Having no more to say but thx to whoever may know whats going on, I hope you all have a great day.

AgelosAp

This is likely a bit depth issue with your normal map and not so much to do with substance. Basically the slight waviness in your normal map is too much for 8 bit depth, and it's more apparent when having a strong gloss.
Have you made each UV island to have its own smoothing group?

dasilvardas

Hi AgelosAp, thank you for answering, you are right I have baked my normal maps again using 16 bit depth and the waviness is gone, I was wondering then, is it better to export normal maps with 16 bit depth in most cases?, and regarding having each uv island to have its own smoothing group, I think I found a work around on how to do it in maya, so that it resembles how you assign smoothing groups in max, this forum says how to http://forums.cgsociety.org/archive/index.php?t-27973.html, based on that, would you recommend using separate smoothing groups for uv islands in maya? Would you mid explaining if it is better or not and why?

Cheers

DRoss3d

@dasilvardas It's definitely better to export your normals using a 16 bit TIFF image at first. Once you're done texturing in substance you can export your normals to TGA or whichever format your engine uses. As far as smoothing groups are concerned, if you have a synchronized workflow, (meaning the normal tangent space is the same between your texturing program and engine) you can keep everything in one smoothing group. I haven't tested this yet, but from what I've seen it works very well. I tend to harden all of the edges that have extremely sharp angles and soften everything else. 

Check out these two threads. It's a bit of reading but it will definitely help you understand which method to use and when and how everything works.

http://polycount.com/discussion/107196/youre-making-me-hard-making-sense-of-hard-edges-uvs-normal-maps-and-vertex-counts/p1

http://polycount.com/discussion/148303/of-bit-depths-banding-and-normal-maps#latest

dasilvardas

DRoss3d, your input is very much appreciated, both articles show pretty much what I was asking for here, and hopefully will guide other artists learning how to do it. it does not matter to read much since all the info seems to be very detailed.

Cheers