Normal map pixelation and baking issues

NealAdamLT

Hey everyone,
I am currently working on a project in which I have to model a Rim for an Aircraft. I finished my High- and Lowpoly recently and tried baking in Substance with Averaged normals.
After baking a 2k map for the whole rim I noticed a weird pixelation around the outer part of the rim.
Since I've already read a lot about normal baking and the high/lowpoly workflow, I assumed it was an issue of too less polys at an edge. But even chamfering the edge wouldn't fix the issue. I tried messing with custom face weighted normals in order to receive a better result, but it wasn't better either.
Now I ask you guys, have I missed something essential?

I am using Maya 2018 and Substance Painter 2018.1.1

The only thing I havent tried yet is streightening the UV Shells, thats what I am about to try now.

musashidan

It's aliasing. Try to lay out your UV islands with straightened borders.

Also, if modeling for real-time then your low poly could be heavily optimised. You could probably nearly half your vert count.

And some of your high-poly edges are so sharp that the bake won't even pick them up. You should soften bevels more than you would usually is baking them to a normal map.

NealAdamLT

musashidan said:

It's aliasing. Try to lay out your UV islands with straightened borders.

Also, if modeling for real-time then your low poly could be heavily optimised. You could probably nearly half your vert count.

And some of your high-poly edges are so sharp that the bake won't even pick them up. You should soften bevels more than you would usually is baking them to a normal map.

Thanks for your help and the Tip with the UV Islands.

Furthermore I know that my LP has a relativly high vert count, but in my case its needed and I am well aware of that

One more question: I know that some of the HP Edges are too sharp for baking, but the more it gets roundish edges, the more it differs from the real object after baking and thats what I want to prevent

Obscura

Wide dilation would help some on reducing those darker pixels, even when the uvs aren't straightened.

NealAdamLT

So I just spent some time straightening the UV Islands and the result is pretty much perfect. There are still some issues around some screwholes, but those are due to the high difference in radial subdevisions betweed high and lowpoly and the 2k map size.

Obscura said:

Wide dilation would help some on reducing those darker pixels, even when the uvs aren't straightened.

Thx to @Obscura for the tip, widening the dilation also improved the edges a little.
@Obscura can you explain what is happening if you dial up the dilation slider? I cant find anything online explaining it.