Mental Ray-Large size renders

[Jozvex]

You may be running out of free ram..

The setting of -1 should be fine, as it means use all that it can. Running a batch render from the command line may just do it, because Maya won't be taking up any memory.

You should just be able to type something like:

Maya -render scene.mb

[Zappa]

HeY!Jozvex,

Thanks for the reply.Well i did try various settings last night too, and i have finally decided to give up on Mental Ray, as it seems to be hogging up too much Ram, also i did a mental Ray surface approximation on the geometry...and its driving me nuts cause the maya native renderer will not recogize that, and im just trying to get it rendered in Maya Software!!i hope i get this sorted out tonight.......aaaaahhhhhhhhh!!!! :scream: not much time left.

Jozvex...cud you possibly....as a test.... run a high res render in Mental Ray jus to see if it works....maybe its a hardware related problem....memory leak....etc...but jus wanna make sure.

Btw..Jozvex, thanks much for your tuts....i was going by that for the final gather thingy...maybe i will have that on my Video Reel!!

Thanks again for your help.
Cheers

[Jozvex]

I test rendered a scene with a few objects and some depth of field at 3000x3000 and it worked ok for me. It was a pretty basic scene though apart from the DOF.

Maya needed 280meg of ram to render it, but it was ok because I have 768. It took a long time though!

And about the tutorials, it's my pleasure! Teaching is one of the best ways to learn!

[Zappa]

Hey!Jozvex,
Thanks for your help, since i have some more time before the deadline now i might try and render in Mental Ray FG.
I will be trying to render a 3000x3000 like you did and hope it works :rolleyes:

btw...did you do a command line render or a single frame within Maya?I have set my environment to create "uncompressed" .tif
but im wondering how you would save it if you have a single frame render from within maya (cause when you save the image maya automatically compresses the image)

Thanks again for you help.

Cheers

[Jozvex]

I just rendered a single frame from inside Maya.

When you render a single frame, you can right click on the finished image and save it in any file type you want.

So you could still save it as a tiff.

[Zappa]

HeY!Jozvex,
Yea, i finally got Mental Ray working,( however the Max size it wud go to is 3000x3000), anyways i got my entry in for Expose, cause at one point i was wondering if i wud make it before the deadline.
Thanks for your help
Cheers:beer:
zappa

[king21]

I have the same problem with mental ray I render on 1280*1280 and maya crashes with no warrning in the middle of rendering done.(i can see half of picture). but than it crashes.

If i turn final gathering of it works fine.

Please help these is bugging me for three days now.

I have windows 2000
AMD 2000
1g ram
geforce titanium 4600 128 ram

[Zappa]

Hi!King21,

The work around is to do run a batch render fr 1 frame, (just set say, 101 to 102 in your render globals), batch rendering from the command line is helpful too and start with a medium size rez and keep pushing it up to where you would want it.Hope that works fr you.

Cheers

[gmask]

You need to lower your BSP settign under memory for mental ray when you get crashes like that. The render will go more slowly as a result instead of crashing. Conversely a small scene can be given a higher BSP setting and render faster.

[chips__]

I had similar problems on a render i did while i freelanced in copenhagen. It was hundreds of cornflakes raining down, and whenever the render would take up more than 1.7 gigs of ram (2 gig in machine) maya would crash. I've been told that this is due to the 2gig barrier that comes with 32 bit processing...i had to render in passes, and convert the really dense parts to .xsi and render in xsi.
OPTERON! PLEASE :)

[DimitrisLiatsos]

Since i have these crashes also and it was mentioned from gmask....what exactly BSP does?????
Forgive me if i am asking this in the wrong place.....

[gmask]

Originally posted by DimitrisLiatsos
Since i have these crashes also and it was mentioned from gmask....what exactly BSP does?????
Forgive me if i am asking this in the wrong place.....

binary space partitioning ( BSP)

This is one of the methods that Mental Ray uses to manage memory.

The other is a voxel grid algorithm


Theoretically the more ram you have the faster it can work but I think since the expansion of ram use is probably exponential that your return for adding more ram to the process is limited especially since basic windows can only assign 1.5GB to any single process. These controls however allow you to force Mental Ray to work in smaller amounts of ram but at the cost of rendering speed.

From the Docs:

"The BSP (binary space partitioning) acceleration method recursively subdivides 3D space into a nested set of voxels, small boxes with triangles in them. It is efficient, but careful attention should be given to the size and depth parameters, which can have a large impact on speed and memory usage.

The Grid acceleration method subdivides on a regular grid of isolines in space. Its memory usage is more predictable, but it may be slower if the geometry is not evenly distributed in the scene.
"

[DimitrisLiatsos]

DANKO !!! gmask:wavey:

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