Normal Map Baking Artefacts

AlexisVO

Hi, I'm currently making a M60 in 3DS Max and I'm having problem when baking normal map in Substance Painter. Here's some pictures of  the scope.




HP

LP


Here's the high poly baked to the low poly in Substance Painter.

I was looking others topics and they were saying to straiten the UVs
Also, there's smoothing groups applied



I tried to change de "Dilatation Width", "Max Frontal and Rear Distance"

I hope someone can help me !

Borx25

Could it be that you have hard edges without splitting the uv map? By continuous single uv island and the many smoothing groups on the Lp it looks like it.
You should split the uv map everytime you split smoothing groups, i.e. you have a hard edge. (The opposite isn't true). So for this case I'd say split the uv map at >=90º degree angles and have a hard edge there (better avoid extreme gradients on the normal maap). Small bevels with less than 90º angle keep them in the same smoothing group and continuous on the uv map.

AlexisVO

I don't know if I 100% understand what you said, but I tried putting seams where my hard edges are cutting at 90º degree angles.





But I feels like that it worked for a part, but it did worst for the rest.

EarthQuake

In general you shouldn't have these small cuts in the low poly mesh, you should let the normal map add that detail. Instead you should add more sides (roundness) to the cylinder itself. Both of these things will help to make your bakes turn out better.

These very thin strips of polygons are going to take up sub-pixel areas on your texture map, which means even if you figure out the best bake settings, it will never quite work. If you had this in game, and the user used a lower texture quality setting, the texture would turn to mush.

AlexisVO

Ok yeah I understand, but if my model is for movie ? How should I model it ?

pior

Is your model for a movie ?

AlexisVO

Yeah I would like to make it for a movie. I already know how to make a low poly for games, but for movie I don't really know the pipeline.

poopipe

For a movie, do everything structural  with geometry 

AlexisVO

What you mean "with geometry" ?

EarthQuake

You're modeling it like it's for a game, for a film asset you would probably just UV the sub-d model, and not bother with the whole lowpoly/baking/etc thing.

In any case, even if this was for a film, your topogoly is bad as well. Again you have a lot of detail for the little inset loops but very little detail for the main shape, so it wouldn't hold up well for film use.

poopipe

As in build it all with geometry. Normal maps are shitty approximations and that's not what you want defining the shape of your object in a movie.  

Basically,  use the high res model . 

AlexisVO

Ok obviously guys as you can see, I'm not a expert. I'm a student, and I'm willing learn everything that I can to improve. So if you want to help me, I'll be very glad.
HP


LP

My HP is based on the LP with support edges. What's the best piepeline ? Should I remake another LP ?

pior

Is your model for a movie ?

AlexisVO

Yeah I would like to make it so it's for a movie.

Andreicus

AlexisVO said:

Yeah I would like to make it so it's for a movie.

I'm not a super expert but from what i know if your model is for a movie= pre rendered with a software like Arnold, Vray, RenderMan etc. the pipeline goes like this more or less:

- Model the High Poly "without any polygon limits" ( of course, don't add details that won't be seen by the camera and don't subdivide the geometry too much if it's not needed )
- In films they don't use normal maps, they use displacement maps to add tiny details like veins or pores in an organic mesh for example for saving on geometry
- After you did the High Poly do the UVs mapping to the High Poly for texturing or you can use a bunch of procedural 3D textures or Ptex if you don't want to map the UVs. You can also use UDIMs if you are doing UV mapping and you need a lot of texture density.
- Texture it in a software like Mari or Substance
- Export the textures in your rendering software ( Vray, RenderMan, Redshift...)
- Setup all the shaders and textures
- Render

The Low Poly version is only used for assets that need to be rigged and animated so the animators can works in real time without waiting 5 hours for a single frame to render, but you shouldn't care about it IMO.

If you are interested in pre rendered stuff i advise you to check out some Gnomon course like the ones of Seth Thompson or Devon Fay, they are both Environment Artist for cinematic and films and they will give you an insight of all the process from 0 to 100.

Also when you model something keep the level of details equals throughout the mesh, ex. if you are making a rifle don't make the barrel super detailed and the scope low poly/with simple geometry, the quality must be consistent  throughout the mesh.