Hello Poser community. I am trying to solve a texture/render issue I am having with a certain scene for an animation I am putting together. Everything looks great in the preview window but when I render the final scene, some of my figures have these weird black patches on them. I have been going through the material room trying to figure out the cause but seems even when I detach almost every node it is still doing it.

I admit I am still novice at some parts of the material room so if anyone can offer me any insight on how i can fix this that would be appreciated. Included are images of the preview window and the firefly render.

Thanks in advance!

Those specific items might be a high or low amount of vertices. Possibly those specific items might need to be remapped . Is this landscape one large model?

The rocks that are giving off the black blotches are separate figures. They are actually asteroid props from a space set I have, re textured to match the landscape prop. But even with the textures that were default I was getting this. The main reason for them is to cover the cave entrance, as it is a square object not meant for distance shots.So the surrounding environment is one prop, the cave another prop and the rocks with the black spots 4 individual figures placed to cover the empty parts of the cave prop.

If you can I would remap first the objects that contain the black spots if hat does not help you might be able to add some certified that may help, I would go for remap first.

I mean vertices

Another thought could be the displacement settings since this is a firefly render. Generally though I've seen this anomaly as a strange leaf-like pattern. Just a thought.

Thanks for the tips. I tried a few things suggested and still couldn't seem to shake the black spots. Very strange. Instead of spending hours messing with the material room i decided I'd just try this freebie rock that I found in the Renderosity free stuff section. Sure enough, no black blots and I think it may actually look better!

Thanks again. I'll have to explore it more when I have the patience for it :)

Self shadowing polys, I reckon. You should try adjusting Shadow Min Bias.

Could also be bad work with the vertice normals, so you may try with "Normals forward" in material room on the poser surface tab. And a other possibility: as far as I can see the structure (under the black spots) on the rocks in preview is not exactly the same as in render. Often the look of a texture differs in preview and render. Try changing the size of the image texture with u and v scale. That may help. And a last chance would be to try a procedural texture instead of the image texture. Something like FBM together with clouds could work well.

SamTherapy is correct as it is self shadowing polygons. I've encounter them all to often. It's an issue with polygon size and Shadow Min Bias on the lights. Below is a close up an image that I'm working on.

Image on the left used a Shadow Min Bias of 0.0250. The Shadow Min Bias on the right is 0.80000.

The polygons are large and shadowing themselves. Also, "Normals Forward" did nothing. If you can, up the subdivision level. The polygons will be smaller.

Damn, I'm good! ;)