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Fess
12-04-2006, 03:08 PM
Hello,

I had a .map file. Used it as a displacement and I got black bands and dark patched in the render.

I changed the format of the .map to .tif via fcheck and Mental Ray aborted when I tried to render.

Can some explaing how TIFF's work with mental ray?

Thanks
Fess

qrichardson
12-04-2006, 06:09 PM
Not sure how tifs work, but I do know that Mental Ray likes your tifs to be in the PC byte order, not macintosh.
So, first you may want to make sure your image is in PC byte order. (if it isn't already)
Then use imf_copy (using the maya shell in your maya application directory) to convert it to a .map file ( again if you haven't already done that.)

HTH.

-quinn

fabergambis
12-05-2006, 12:31 AM
I think MR doesn't like TIFF format very much and if you're not forced to use it, try to convert the file to TGA or IFF. I prefer to use TGA, MAP or IFF and never got problems.
Are you sure your dark patches depend on MAP file?

tfritzsche
12-05-2006, 03:47 PM
Hi Fess
one of the major differences for Mental Ray between .tif and .map is that MR will load .tif in memory when it renders. Map files are multi-res files, it has a full res image , half res image and a 1/4 res image in the map file, and MR uses the appropriate version when needed from disk, so it does not need the full res file in RAM, it reads the part of the file it needs from the approprate res version from disk.
Your MR abort when using a tif file might be RAM related, in the the render globals MR tab translation section turn export verbosty to detailed messages to see what MR chokes on. the messages are sent to the output window/Console.
As for the render issues when you were using the map file, these might be related to normals or a bad approximation node or ..., might help to see the render.

good luck
thomas

Fess
12-05-2006, 09:02 PM
Let me start over my explaination....

I'm on 6.5 unlimited.

I had sand.map file used as a shader for a nurbs plane.

When I rendered in Mental Ray, the image came out almost totally black even with tons of active lights.

Someone told me that somewhere between maya 6 & 7, they managed to break the .map format. So I should convert to something else.....

so, i first opened the sand.map in FCHECK to look at it. I then saved it as .tiff, applied it to the shader used for the nurbs plane, rendered & mental ray aborted.

Then I remember I could use the imf_copy utility as quinn suggested:
imf_copy sand.map sand.tif

applied the .tif to the shader used by the nurbs plane, rendered & had success.

Okay, so it was bothering me that the .tiff saved through FCHECK did not work. Then I went into Photoshop and was looking at the 8,16, 32 bit modes etc.

So, basically the question that I'm left with is how do you make a .tiff in photoshop that works with Mental Ray?

one of the major differences for Mental Ray between .tif and .map is that MR will load .tif in memory when it renders. Map files are multi-res files, it has a full res image , half res image and a 1/4 res image in the map file, and MR uses the appropriate version when needed from disk, so it does not need the full res file in RAM, it reads the part of the file it needs from the approprate res version from disk.
Your MR abort when using a tif file might be RAM related, in the the render globals MR tab translation section turn export verbosty to detailed messages to see what MR chokes on. the messages are sent to the output window/Console.
As for the render issues when you were using the map file, these might be related to normals or a bad approximation node or ..., might help to see the render.

Tom, I don't have the render, but I got 3.93gigs or ram and its a simple scene.

I think MR doesn't like TIFF format very much and if you're not forced to use it, try to convert the file to TGA or IFF. I prefer to use TGA, MAP or IFF and never got problems.
Are you sure your dark patches depend on MAP file?

faber, yeah I'm sure its. the .map now. TGA worked also but I just wanted to get the ins & outs of .tiff and Mental.


Not sure how tifs work, but I do know that Mental Ray likes your tifs to be in the PC byte order, not macintosh.
So, first you may want to make sure your image is in PC byte order. (if it isn't already)
Then use imf_copy (using the maya shell in your maya application directory) to convert it to a .map file ( again if you haven't already done that.)


Quinn, thanks for that info...


Need a drink
Fess

acidream
12-05-2006, 11:45 PM
It needs to be a RGB tiff even though the displacement is only b/w.

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