Hi everyone,
While working on texturing a new modle I made, I've run into a strange problem that I've never encountered before.
After I apply the texture to the model, and then render it, a weird anomaly shows up in the finished product. It's a black splotch that's not there on the texture itself. Can anyone shed some light on ths for me? If so, pleeeeeeeeaaase tell me that it's simple to fix. Not something like "you'll have to recreate the whole model to get rid of it". See below for an example of what I'm talking about. The red circle shows the area of the texture that corresponds to the part of the model where the problem lies, and just to the right, and below it, is a small square that shows the rendered model, with the funky black creeping unknown. Any advice (especially if it's good news!) will be appreciated.
Thanks -

Steve 

have you tried checking Normals_Forward on the PoserSurface (main) node of that material? have you tried rendering without shadows?

Pjz99

What exactly is Normals Forward? I always check it for my hairs but never really understood it's purpose. We're to select it for clothing also?

It shouldn't ever hurt, but it may not be useful - see, Poser polygons have two sides.  One side only is considered the "normal", or the useful side.  Depending on the model, it can happen that the normal is facing away from the camera during rendering, and that polygon (and/or other polygons like it) may not render correctly or at all.  Enabling Normals_Forward forces the renderer to consider whichever side of the polygon that is facing the camera at render time to be treated as the normal, so it should make a backwards-facing polygon render correctly anyway.

Gotcha.

I'll always enable it...just in case.

Thanks!

It looks like there's a mapping problem or some stray geometry.

If you have UVMapper Pro, use the Checker texture, to check the mapping in that area.
If you only have UVMapper Classic, find/make your own checkered texture.

I just tried rendering with no shadows,and it didn't help at all. As far as "normals forward". Is that an option in Poser 5? I l've never heard of that, and I just looked in my materials room at all the nodes and I didn't see anything like that.

I never used Poser 5 so I don't know, sorry.

nruddock, I only have UV Mapper Classic, and  use it to make all the textures for all my models.... but I'm not sure what you mean-

If the black part seems to move around, it may be a case of Poser Indecision
Syndrome.  When two surfaces share the same material, and they are in
the same place as seen from some angles, Poser will sometimes
get confused. 

I can't really tell from the picture, but you may have a plate just behind the screen,
both taking the same material?

Here's a case where I worked through the mystery:

http://www.renderosity.com/mod/forumpro/showthread.php?thread_id=2704823

In that case the two surfaces were the top shelf and middle shelf of
the bookcase.

The solution is to give the competing surfaces different material zones
with different names.

No, the black part doesn't move. This is confusing. I'm thinking that it's like nruddock said - there's some stray geometry in there somewhere. It looks like it because of the way the black area is n a triangular shape across part of the flat surfaces. Not sure how to handle it though.

Can you just show a wireframe...

Yeah - stand by......

Here it is....

Attached Link: http://images.google.com/images?q=UV+checker+texture

Is there another geometry right underneath this one?  If so it could be touching it.  It looks like it could have something to do with inverted verticies.  Try in UV inverting just that one section, save it and look at it again in Poser.  Sharen

How did you model that part, with extrude?  I kind of agree, it may be that there is some geometry behind what you can see there.

you need to do a weld on that part of your model. You undoubtedly have a face behind that face sharing the same space. I have seen it may times.

The way I mdae that part wasn't with extrude... the whole thing is a large gun, made originally as a .obj file. Then I took another .obj file of a small open top box, stuck it on the side, and exported the whole thing as another .obj file, then converted to a prop. So the small box that seems to be the crux of the problem does indeed have a surface beneath it. But I didn't think that would be an issue since the box top was open.
SAMS3d, I'm not sure what you meant when you said
"Try in UV inverting just that one section, save it and look at it again in Poser."

You can invert a surface if it is black in Poser.  Sometimes when a surface shows up black in Poser is because it is sort of inside out.  If you invert it in UV mapper it is turned to the right side and should not be black in Poser. 

But if you have a surface that is next to, I mean really close to another surface, Poser looks at it as 2 surfaces and will turn it black.

2 separtate subjects here.  Sharen

I see what you mean about inverting it in UV Mapper, and it makes sense. My only question is.... how? I'm thinking it's probably pretty simple, but I'm having a hard time wrapping my brain around it....

In the UV mapper you have, I think it still has this option.....select your verticies, then click tools....then facets, then invert....that should do it.  Sharen

I think this is where UV Classic and UV Mapper Pro differ. I only have Classic;
I selected only the vertices that seem to be causing the problem, then went to tools and the only options at that point are fix seams, split vertices, weld vertices. I don't see any option to invert them. 

Maybe it isn't under tools....I know the option is there, because I use to have to do it all the time.  Look around, I will try to download classic and see if I can find it.  Sharen

Your right, it is not there....hmmmmm....I must have been using the first pro.  I am so sorry to have mislead you.  Sharen

No problem - I appreciate you taking time to help me out. You've given me a few ideas about how to try and solve it, so that's what I'll be doing this evening. And I don't mind, because I'm learning something new! So, my thanks to you!

Steve

I think it's a similar problem I ran into some weeks ago -
have a look here:

http://www.renderosity.com/mod/forumpro/showthread.php?message_id=3303147&ebot_calc_page#message_3303147

Import options - Make Polygon normals consistent
Group editor - Flip group normals