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imagecube
08-24-2011, 09:07 PM
I got this strange rendering error. The frame buffer looks correct but the file itself is wrong. the attatchments show what they look like in frame buffer and imf_disp window.
the strange thing is all the passes are right just the master beauty is way off. anyone has any idea?
http://i304.photobucket.com/albums/nn200/imagecube/imf_disp.jpg
http://i304.photobucket.com/albums/nn200/imagecube/FrameBuffer.jpg

imagecube
08-29-2011, 05:43 PM
I am on maya 2011 hotfix 3 on win7 64bit.
mental ray 3.8
all shader are mia_X_passes. rendeder into 16bits EXR with some render passes(2d motion vector, diffuse, normal, etc..)

running out of idea what causes this mess. anyone can help?

or I can send you a simple scene

Bitter
08-29-2011, 06:28 PM
I've never seen that, if you have a simple scene it might help.

imagecube
08-30-2011, 01:33 PM
Bitter, I put it here.
https://docs.google.com/leaf?id=0BzrS_alKYSPVODJkN2Y0ZmEtNmY1My00ZDE3LWJiZDUtNTUxNTI4ZDNmYTA4&hl=en_US

it is a very simple scene just a sphere and a cam. rendering with 2d motion vector pass. let me know if you can re-produce the bug. thanks.

BlindFish
08-30-2011, 08:00 PM
I think if you set your framebuffer to 32 float instead of 16 half, it will work. Or another solution is that you can force mentalray to render the different passes to separate files(by putting <RenderPass> in the file name)

Recently mentalray don't like when there are buffer which are set to 32bit float and the main framebuffer is set differently

Bitter
08-31-2011, 07:14 AM
I don't think the framebuffer is the problem, I generally always render to 16-half and some framebuffers will be 32-bit float instead (like z-depth) by default.

I could not reproduce the problem so I don't know where the problem is, it renders as expected for me with ONE exception.

You are rendering with Raytrace primary rays. This is fine. Except the Maya toxik2D vector pass doesn't work unless you render with Scanline primary rays.

Feel free to complain to Autodesk, I have. :D

You can render raytraced motion blur just fine with Unified Sampling.

imagecube
08-31-2011, 01:13 PM
Thanks for all your help. I will try to switch the file format to 32bit to see if can solve this issue.

I have rendered 16bit exr with full floating passes in previous projects. everyting was fine.
the problem I have is the frame renders OK in the frame buffer but the file itself is messed. I used maya 2011 which does not have unitfied sampling since MR comes with it is 3.8.
yes, in 2012 the problem seems to be gone.
The reason I have 2d motion vector pass in raytrace mode is to keep the frames align with other renders.

imagecube
08-31-2011, 01:24 PM
BlindFish, you are right. 16bits main buffer with 32bits passes causes the mess.
I tried some other 32bit passes like normal, motion vector, depth ect.. when I render into 32bit exr, all behave what they should be.

Thanks. I need to worry my storage space now. :)

I think if you set your framebuffer to 32 float instead of 16 half, it will work. Or another solution is that you can force mentalray to render the different passes to separate files(by putting <RenderPass> in the file name)

Recently mentalray don't like when there are buffer which are set to 32bit float and the main framebuffer is set differently

BlindFish
08-31-2011, 03:24 PM
If you want to save some space, you can use the other solution which is to render the buffers on separate files(but maybe that would mess up your comp workflow).

It useed to work for me to with maya 2010 but with 2011, sometimes it behaved strangely...

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08-31-2011, 03:24 PM
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