OTOY Forums

The problem I'm having is that it appears that when I render multiple frames the material of the lights get swapped out for other materials in the scene on all the frames but the first one. This doesn't happen every time but in 25% - 50% of the renders.

The image below shows how it should look (top) and wrong renders (middle + bottom) The top image is the first frame of a render. The others are later both later frames. Middle and top are not in the same batch render but in different batches. As you can see the light becomes a shaded plane in the faulty renders. It looks like it's using a random material that is already in the scene. To test this theory I changed the material colors of the spheres. The only "workaround" I have come up with is setting the animation mode to global. This unfortunately leads to a serious increase in rendering times.
I'm running Octane 2.04 in Maya 2014.

Edit:
1: At first I thought this only happened in the batchrenders but I just found out it also sometimes happens in interactive mode while working on a more complex scene.

2: The problem only occurs with lights set to moveable proxy. When I set all the lights to global it doesn't occur. Unfortunately my lights need to be animated.

Hi Wenneker,

Are your lights octane light nodes or geometry with a diffuse material and emission? If they are octane light nodes then I think this is a bug that has been around for a while with movable proxy lights but I had been unable to get a simple scene to repeat the behaviour. I had also thought the lights were just turning off randomly but as my scene was a very dark scene it's entirely likely that they were randomly picking up another material in the scene, visually the result would have looked like the light had just gone off and yes it happens for me either changing frames in an interactive or batch render.

If this is the same problem then hopefully JimStar can now recreate it and track it down. In the mean time I've found that if you recreate your lights as emissive geo using a diffuse material with emission their behaviour seems more consistent, I haven't done enough tests to say they work perfectly though.

T.

Where should I send the file?

Unfortunately it doesn't occur as often in this simple setup as in my current project where it happens pretty much every time.

Just zip up your scene file and attach it to a post here. JimStar should find it.
Yeah, that was my problem, every time I tried to make a simple scene with the issue it would work perfectly.

T.

This is the scene.
I get the most incorrect frames when I batchrender the sequence in small chunks from a commandline.