Exterior Night Scene

[glorybound]

Hi-

I have an exterior night scene that is illuminated by an hdri, a couple ies lights, and a dozen vray plane lights. I have tried almost every vray setting and combination of settings, but my render times are huge. I also have a lot of proxy's... any advice? I am talking 20 hrs for a prepass.

help!

[joconnell]

Hmm - if you've a lot of proxies do you get messages like "Unloading geometry" appearing on the render progress bar? If it's something like this it means that vray doesn't have enough memory to keep the proxies in memory while making your lcmap and irmap so it's constantly swapping them in and out. If this is the case, up your "dynamic memory limit" in the top left of the "vray system" section of the render dialog - the default value of 400 megs is quite low for a lot of shots and it's choking the amount of render time geometry vray can use. Check the windows task manager to see how much memory vray is using compared to the amount of system ram you've got - it might also be going the other way, using too much memory and switching over to virtual memory which is gonna be sloooooooow. Also try turning your proxies on and off, ies on and off and so on until you find the bit making your scene slow.

[glorybound]

All good advice joconnell and I'll look intot he scene further. My memory is set to dynamic 8000MB on a 12GB workstation and each of my slaves have 12GB. I guess I can check to see if it is to high, like you said. I'll also turn things off to see what is causing the slow render times.

[joconnell]

Is this one of the biggest scenes you've done so far? I've got a few scenes with a lot of proxy trees recently and they were the biggest bits I'd put through our farm so far - Oddly enough the render farm with 12 gigs of ram each fell over on lots of scenes where as the workstations with 6 were fine. Might even be something like hyperthreading causing the machines to split their ram with the "virtual" processors made by HT and choke themselves for ram?

[glorybound]

so I'll try to lower the ram allocated to something like 4000mb and see if that works.

[glorybound]

so far I have found out that:

dynamic memory 2m 37.2s
auto memory 1m 52.7s
and smaller render region division speeds things up to 1m 32.7s

This is with all lights, except for dome HDRI, and proxy's turned off.

[glorybound]

Okay. I systematically went through everything and multiscatter is bringing everything to a halt. everything is proxied, but with multiscatter it'll sit for hours and without it takes minutes.

[voltron7]

I've read on here somewhere to avoid using light cache with MS/VRS...
What are you using for primary and secondary?
Whenever I have used VRS, the render times were always bigger if using light cache, sometimes causing a crash.

[glorybound]

yes. I even tried BF as first bounce with nothing for second, but it still crawls. I just randomly placed the tree proxy's and removed the multiscatter. placing just as many proxy's as the multiscatter was placing, and it fly's. There is something wrong with multiscatter under WIN 7 and 3DS MAX Design 2011.

I think when people sell 3rd party plug-ins they need to specify what setup they have because I waisted thousands last year on plug-ins that do not work.

[glorybound]

speed

I just rendered out a full scene with 2x the settings I was using with multiscatter objects and it rendered in 56 minutes, With the multiscatter object sat at precalc for 14 hrs.

[glorybound]

amazing! I removed multiscatter (mentioned above) and tried Autograss, with my finger crossed, and autograss dropped buckets. I reverted back to good old displacement for the grass it is renders super fast and looks just a nice as the expensive plug-ins.

[tolgahan]

Hi Parker.
I have got a same problem.I thınk the main problem is lightcache and proxies
Here is my night examples and its too slow
And pls fallow this thread

http://www.chaosgroup.com/forums/vbu...nd-huge-scenes

[glorybound]

nice images.... lightcache and proxies don't work well and BF is slow in its nature. Doesn't brute force analyze every pixel? if you use proxies you general have a lot of something so why would the best option be something that will be slow anyway?

[PIXELBOX_SRO]

Try a ForestPack instead of multiscatter Bobby.....you can get the free version for your trial.
This wil help you tackle the issue with multiscattering whether its caused by Multiscatter OR Vray OR setup

Im still at home now but if you PM me to remind me, i would send you a rendering setup that ive used for rendering with multiscatter....

[tryharder]

... did you download the new multiscatter .. fixes the memory leaks ... had the same problem ... now it works for me

Klaus