Alpha levels

[bradon]

I'm having an issue that pops up on some of our renders where the alpha level is not full white. it has a value of .9 or so in EXR floating point or about 250 when we go to 8 bit mode in our composit software.

the problem occurs usually for just one frame and happens on adjacent frames. so one frame will be fine and the next frame will be sort of faded.

at this point that is all the information we have. we are still looking for a good case study file to share with you guys. unfortunately we have been unable to reproduce the problem but it has showed up in 2 independent maya scenes. and its not on every render but only every so often do we get this problem. usually re-rendering the frame packet fixes the issue.

we are using the build from 5/28.

any info would be helpfull.

Thanks,
Bradon

[bradon]

I would like to revisit this topic? no responses yet. this is actually turning out to be a bigger issue. its happening in most of our files now. as far as i can tell all i have to do is re-render the frame and the alpha problem will correct itself. however the issue is that i render thousands of frames and its not in any noticable pattern yet so i have to frame by frame check each alpha level and then re submit the individual frames with bad alpha. ill be looking into this issue more closely now that i have my other vray problem solved but i wanted to see if anyone experienced simmilar issues?

[Zdravko]

Would you please send us a scene with that issue to: vraymaya@chaosgroup.com

[bradon]

well the issue is happening to us in a lot of files. problem is i dont have a simple scene file. I only have large cad scenes that have hundreds of parts with lots of vrproxy. I can try to get with my team and see maybe we can archive somehow and send to you but it sort of a bummer because the scenes are really complicated ones.

[vlado]

Do you have lots of noise in that areas? Is it possible that there is overlapping geometry there?

Best regards,
Vlado

[bradon]

the alpha is completely faded to a value of .9 for the entire object so the object is for example a refridgerator so it has many objects and many materials. some reflective some refractive. but the interesting thing is the entire alpha is faded for the entire object.

http://i245.photobucket.com/albums/g...pha_aeSnap.png

http://i245.photobucket.com/albums/g...phaChannel.png

http://i245.photobucket.com/albums/g..._goodALpha.png

http://screencast.com/t/MjVmYjYyOD