render woes!

[cdavis]

Hi,
When rendering a single frame from an animation in maya with vray frame buffer , it just renders it.
When I batch render it it goes through every frame first saying updating frame, 1 then 2 & so on & it seems a really slow process, even before its rendered anything. Is this a normal procedure as i dont remember seeing it when doing other animated sequences. Also from this scene the render time in maya is 8 mins-10 mins per frame, when the batch render eventually starts , the frames are taking 25-30 mins per frame. really confusing me this scene . The scene consists of some vray proxies & a cached particle sim with an instantce replacement on it & some vray sub-d'd objects all heavily shiny reflective objects. So when I test on single frames in maya it all looks good, but I cant get a sequence out as I have 400 frames & am getting about 2 frames per hour in batch.

[djx]

It sounds like your batch render is not finding the particle cache. You could test this theory by deleting all the particle stuff, saving to a new name and batching that to see if it works better.
Are these nParticles or old maya particles? With nParticles I always put the full path to the cache. With maya particles, the cache is always relative to the project, and this can cause issues.

[aweidenhammer]

We ran into an old Maya bug I never knew about on our last project. we only cached one big particle system in our scene. another particle system was super simple, and we figured did not need a cache. (It was only 50 particles). Big mistake. (This was with old particles btw).

If one particle system is not cached... no matter how small... the larger (cached) particle system will do a runup every frame on the farm. Moral of the story: cache ALL particle systems. That fixed our runup issue, and frames were predictable.

Andrew

[cdavis]

they are nParticles yes. Does caching to a single file or a file per frame make any difference ?

[aweidenhammer]

we didn't test that. But we cached to a file per frame with "all" selected. That said, we were using old particles. Don't think the bug exists with nParticles, but I haven't tested.

Andrew

[ALFRED_ST_MEDIA]

we've also dealt with many issues in maya 2011 over-writing the workspace.mel file with a stub version, which doesn't have an entry for nparticle or particle cache files, so the render was fine locally, but on the farm, pandemonium. I've you've cached your particles and still have the issue, check the workspace.mel file to see if it's correct. If not, copy a good one over it, then change write permissions to it and try batch again.

good luck!

-ctj

[cdavis]

after testing, writing to a file per frame sped it up quite a lot.