Strange seams?

Dismembered · Nov 2010

So I have been working on a new project, for longer that I would have liked and I have gotten to the rendering stages. Well I have been running across a bit of a hiccup. When I render there seems to be a normal seem running down the side of the street lamp. But I decided to take the normals off to see if that was the problem and the seam was still there, and I did the same for the diffuse.

I did notice that if I do a close up render the seam is gone and the further away I get the worse the seam seems to get, which confuses me. Does anyone know why this is happening, or how to fix it?

Mark Dygert · Nov 2010

Probably need more edge padding? It looks like the "void" or negative space around your UV shells is bleeding into your image area. This happens quite a bit with textures that are "MipMapped". The solution normally is to bump up the padding around the UV shells.

Dismembered · Nov 2010

I am not sure that is the problem. The problem areas have nothing but a default shader applied. Is there any other possibility? And as I stated the "seam" only shows up from a distance.

renderhjs · Nov 2010

try adding a tesselation modifier to it, to subdivide the model without changing its shape. Tesseleation usually fixes rendering issues like wonky shadow maps or stuff like that. I think its the renderer that sometimes does approximations within its optimizations to run better.

Dismembered · Nov 2010

try adding a tesselation modifier to it,...

Tried this and I am still getting the same results.

Eric Chadwick · Nov 2010

How is this being rendered? Realtime or offline? Which software, what settings? Any textures on the model? Can you show the UVs?

Dismembered · Nov 2010

-3ds max
-Mental Ray (Final gather enabled, Lanczos filter)
-The "seam" shows up whether it has a texture on it or not. Pictured above is just has a default shader on it.

Here are the UVs.

Eric Chadwick · Nov 2010

I bet it doesn't happen with the scanline renderer? Probably something in your final gather settings. Tweaking time!

Oh, it could be that your mesh is duplicated there, like doubled-up faces. Have you checked for this?

Dismembered · Nov 2010

Well it wasn't doubled faces, but it was definitely something in my FG settings, just as a quick test I turned the preset up from draft to medium and viola it was gone. I am going to have to spend a bit of time to figure out exactly what caused it, thanks so much Eric!

Eric Chadwick · Nov 2010

Ah cool. Yeah draft can be noisy, that's why it's fast! Try setting it back to draft, and increasing the Rays per FG Point... ? Been a while since I messed around in there.

Dismembered · Nov 2010

Nope, it ended up being Initial FG Point Density. Had to turn it up to about .8 for the "seam" to disappear.

Strange seams?

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