Image Renders Different on Identical Machines

[bradon]

I have a strange issue still trying to sort it out. I have a file that renders nice and clean on my local workstation computer, but whenever I open up the file on a different computer or render on the farm the render looks different. theoretically there should be no difference because all I do is open the file and hit render on machine A it looks good and on an identical system B looks grainy and poor. To throw a wrench into this. I have a third identical machine C, machine C renders good like machine A. so im sort of at a loss as to what is causing the render differences on 3 identical machines. Also I use a farm of 30 machines and all of them produce the poor grainy result.

Im using the nightly build from 5/28 on all machines.

specifically the grainy an poor quality looks in the Irradiance/Light Cache map. the method is set to single frame on both IR LC. I can see many more splotches in the shadows. so for any one who may have had a similar issue or can suggest anything to try here are the images.

http://i245.photobucket.com/albums/g...omparision.jpg

here is my render settings for this file captured in a mel preset
https://www.yousendit.com/download/Y...SU9tMEpFQlE9PQ

Thanks.

Bradon

[vlado]

Are you using the standalone or you are rendering through Maya? In either case, it is possible to get me the scene (.vrscene or .mb/.ma) to vlado@chaosgroup.com ?

Also, are the machines using different regional settings by any chance?

Best regards,
Vlado

[bradon]

well yes it might be possible to get you the .mb there are a ton of proxy in the file. so the vrscene might be better. we are rendering througth maya batch. I tried BOTH throught the GUI and also with MUSTER same error in both cases.

we did a bit of testing it looks like when i copy all my maya usr pref/scripts/shelves etc. directory to one of the failing machines it seems to fix the problem. obviously i dont want to have to do that with EVERY machine also because it will overwrite any existing user preferences that we may need. so were trying to find the ONE file or line of code that actually made a difference. we think its in the general maya user pref mel. i havent looked yet to find the vray specific line code in the usr pref mel that causes the error. will do and let you know if i find anything

[bradon]

opp scratch that its Definately NOT the usr pref maya file. we trashed that and it has no effect on the error. perhaps some other vray XML pref file somewhere?

[bradon]

another thing we found out is if we create a vrscene file on the computer that renders properly and do a vray standalone render on a machine that was rendering bad, the vrscene render is fine. so vrscene is ok so long as it was created on the host machine from maya that was good. so we determine the error is with maya when it creates the vrscene for rendering. since i create the vrscene on the ONE machine that does this properly we can render on the machines that were previously failing. our pipeline is not set up for this though, normally we use a maya batch with muster so we ideally we will find the reason why the vrscene creation is different on some machines than others. when we do a text edit comparision it looks like there is only one line of difference i think it was a line with an "intensity=3" vs Intensity"=1.INF" or something. im manually fixing in text edit and will post the results.

still we did find if i copy the usr prefs the whole thing over to another computer it seems to fix the problem but this is not really an option for us. we still need to find the one preference file that is causing the error in the vrscene creation.

[bradon]

ok actually to be more descriptive. I tested to manually make a vrscene on the bad machine. and it looks like the translation was fine when instead of rendering i only make the vrscene with the translator tab. (with the exception of the one intensity line being out of range. this was the actual difference " intensity=1.#INF;" so after i manually correct this it renders fine) so something is different between the vrscene when you render and if you make a vrscene when you use the translator. even though when you render out of maya it creates a temp vrscene and renders that, that is somehow different than when i make a vrscene with the translator. im trying to track down the temp directory where the tmp.vrscene is created on the local machine at rendertime from maya to see if i can see any differnces in the text.

hope all this makes sense. im not sure exactly how to describe the problem.

[vlado]

There is no temporary .vrscene file created when you render inside Maya; the scene is created directly in memory. A .vrscene is only created if you use distributed rendering, so that the scene can be transferred to the render slaves.

In any case, this particular issue was supposed to be fixed already in the latest builds - can you try a more recent one?

Best regards,
Vlado

[vlado]

Can you also show me a little more text around the 1.#INF line? Like what kind of object is this - it is probably a light, but what type of light?

Best regards,
Vlado

[bradon]

yes its one of the rec lights HOWEVER this issue is unrelated to my problem, but still was an issue

LightRectangle lights1__VRayLightRectShape15 {
enabled=1;
transform=Transform(Matrix(Vector(31.07269, 0, -16.10655), Vector(-1.315288, 136.4434, -2.53744, Vector(20.03666, 0.9120131, 38.65464)), Vector(199.6906529463962, 0.1047120994168541, 224.925756738023));
color=Color(1, 1, 1);
shadows=1;
shadowColor=Color(0, 0, 0);
shadowBias=0.02;
photonSubdivs=500;
causticSubdivs=1000;
diffuseMult=1;
causticMult=1;
cutoffThreshold=0.001;
affectDiffuse=1;
affectSpecular=1;
bumped_below_surface_check=1;
nsamples=1;
diffuse_contribution=1;
specular_contribution=1;
channels=List(
);
channels_raw=List(
);
channels_diffuse=List(
);
channels_specular=List(
);
units=1;
intensity=1.#INF;
subdivs=8;
storeWithIrradianceMap=1;
invisible=1;
affectReflections=0;
noDecay=0;
doubleSided=0;
lightPortal=0;
u_size=1;
v_size=1;
ignoreLightNormals=1;
rect_tex=AColor(1, 1, 1, 1);
use_rect_tex=0;
tex_resolution=512;
tex_adaptive=1;
}

[bradon]

So It sounds like this is a known issue then? can you explain to me what to do to fix the problem. I guess we can upgrade to the latest nightly and see if that helps. we have a large render farm though and to do this manually every time there is a slight bug fix is sort of a pain until we can automate our system better becasue we have to manually log in and install on 40 computers. not fun. so if there is any more information you can provide as to what is causing this error and how to fix it that would be really helpfull. the only thing we have found so far is to copy my maya user preferences to each render machine, (which would be a pain to do on 40 machine, plus its not really an optoin because it blows away any existing prefs that we may need) so if you know which preference causes the error can you share that so maybe we can figure out how to automate a patch for now until we can upgrade to the nightly later nightly builds.

[bradon]

well after messing around with this for a day and a half the problem seems to have corrected itself!? Unfortunately I no longer have the ability to consistently display this error. im not sure what fixed it but maybe some preset got saved or wasnt loading properly for whatever issue. we started to render with the vrscene instead of the maya batch because it was more stable result... maybe it just needed a kick in the pants, who knows? possibly a network issue I guess well never know! anyhow just wanted to say thanks for the support and suggestions.

[vlado]

Ok then; will take a look at that code just in case. Can you tell me if the light intensity was animated in the scene? (Doesn't look like it, but just in case)

Best regards,
Vlado

[bradon]

light intensity was not animated but looks like there was some non moving keyframes on the translate/scale/rot

im emailing you more detailed information

[bradon]

There is no temporary .vrscene file created when you render inside Maya; the scene is created directly in memory. A .vrscene is only created if you use distributed rendering, so that the scene can be transferred to the render slaves.

In any case, this particular issue was supposed to be fixed already in the latest builds - can you try a more recent one?

Best regards,
Vlado

out of curiosity is there a way to save have maya batch save the temporary vrscene file when its finished rendering? we still experience a few wierd issues... possibly its user error :P so we want to compare frame by frame what actually got rendered from vray.