Render Erorr (Artifacts)

Fragg1960

I'm using Studio 4.0 Pro on Windows 7, 64-bit. No problems with the program in general. I've been working on a scene for a while playing with the Visual Style shaders on sale here in the store.

Everything was working great for a while--all my test renders were all fine. Suddenly yesterday I started getting weird colored pixel artifacts on the image. I didn't do anything drastic to the image and I had rendered the image before with all the image elements in it with no problems. Has anyone seen this effect before, and how can it be fixed? I spent a lot of time on that scene and I'd really rather not have to re-do it due to a rendering software error.

It also only shows up when I render with 3DLight, not when I do a preview render or a hardware assisted render. Any ideas or suggestions?

mjc1016

Switch to raytraced shadows...it's a known, long standing problem with ALL Renderman renderers (some more than others, but they will all do it on occasion...3DL does it a lot)...it's basically something deep in the code of the shadow algorithms.

Shifting the camera or light position slightly may help, too.

Zilvergrafix

Fragg1960 said:

I'm using Studio 4.0 Pro on Windows 7, 64-bit. No problems with the program in general. I've been working on a scene for a while playing with the Visual Style shaders on sale here in the store.

Everything was working great for a while--all my test renders were all fine. Suddenly yesterday I started getting weird colored pixel artifacts on the image. I didn't do anything drastic to the image and I had rendered the image before with all the image elements in it with no problems. Has anyone seen this effect before, and how can it be fixed? I spent a lot of time on that scene and I'd really rather not have to re-do it due to a rendering software error.

It also only shows up when I render with 3DLight, not when I do a preview render or a hardware assisted render. Any ideas or suggestions?

would be more easier if you could post the image.

Fragg1960

mjc1016:

Thanks for the tip, but I think I'm screwed. I tried rendering with raytraced shadows, with the software rendered shadows, with no shadows, deleted all the lights and tried--render is still full of artifacts no matter what I do. I even removed background elements in the image and still have the artifacts.

Here is a close up of what the artifacts look like (attached). The render shown is with all the lights removed from the scene.

nightwolf1982

Try posting a screenshot of your render settings

Zilvergrafix

Don't have the Visual Style Shader, but Anime Shaders only, the only thing I could asume is some parameter setting wrongly in Surfaces Tab.
thus, verify your Render Settings Tab, if is only visible on 3Delight and not on the others render ways maybe you have some parameter overdone/exaggerated.

some tips: save your Material settings, change the skin material with another textures, like M5 for example and render with 3Delight.

I had similar issues with Manga shaders but was my mistake play with settings in surface tab and not being clarified of "what is this and what does it".

sriesch

I have recently had issues myself, although nowhere near that drastic. I can't zoom in on your image to tell if I was seeing the same thing or something different. The problem I had was intermittent though; sometimes it would work, sometimes it would fail. I did notice that at least one time it failed the same way twice on two renders in the same session, but worked after exiting, restarting, and rendering with no changes. I made numerous modifications to my scene with the issue coming and going, but was able to complete it and render it without problems in the end. If you can, try re-rendering in a fresh session and see what happens.

mjc1016

Yeah, that's something on 'overdrive', not the standard artifacts that show up with shadowmaps.

Fragg1960

Thanks all--I'll have to play around with the surfaces to see what happens. The thing that bugs me is that the same scene was rendering fine as is--and then all of a sudden it started to render with the artifacts.

I tried rendering an earlier saved version of the scene (it included the surfaces using the Visual Style shaders) and that rendered fine, so it may have been something I did with the shaders later on. But if that's the case, I don't get why it would render okay for a while and then just go South.

Fragg1960

Found the problem.

It was a single object in the scene that was corrupting the render --a small monocle I was using that I had exported out of Google SketchUp and imported into Studio as an .obj. For some reason the 3DLight engine did not like that one object (but this one object also caused other objects in the scene to pixilate in it's presence).

I removed the offending object and everything else in the scene now renders normal. Wouldn't have guessed that a single object was the problem.

mjc1016

Umm...exported from Sketchup?

Are you sure that you only had the geometry of the monocle? I've found that sometimes exporting from SketchUp can add in extraneous geometry.

KinnieM

edit: glad you found the problem.

However sometimes when this problem occurs saving the scene as a rib file and rendering it in the separate 3delight render engine can help to see if those artifacts appear. I had one scene where they appeared in studio's rendering and disappeared after rendering in the independent 3Delight.