Let’s pick up on the topic Let .mi export… and show how to export to .mi from 3ds Max.
Step by Step Procedure
You can simply export your scene to an .mi file in 3ds Max when using mental ray as Production renderer.
- Go to “Rendering/Render Setup” or press F10.
- Choose NVIDIA mental ray as Production renderer.
- You find “Export to .mi File” in the “Processing” panel in the “Translator Options” rollout.
Note: All the controls (but the “Browse…” button) are initially greyed out until a filename is specified.
- Press the “Browse…” button to spectify the .mi file output.
- Render or press Shift+Q. Instead of actually rendering, the scene is exported to .mi file.
You can use mental ray Standalone to render the exported .mi file.
Note: When rendering with Standalone you might see errors about missing SubstanceShader.dll and PointCloudShader.dll. These errors can usually be ignored and do not prevent proper rendering. You might want to delete the corresponding link in the .mi file to prevent these errors to show up (see link directives at the top of the .mi file).
User Interface
“Export on Render”
Uncheck “Export on Render” if you want to render to the viewport instead of export to .mi file.
“Un-compressed”
If you choose to export “Un-compressed” (the default), the three dimensional vectors in objects are echoed in ASCII format. If you uncheck this option and choose to export compressed, vectors in objects are exported in binary format resulting in a smaller .mi file size and in exact floating point precision. See also the section “Export Binary vs. Ascii” in the post about exporting to .mi file in Maya.
“Incremental (Single File)”
If you select “Incremental (Single File)” options, animations are exported as a single .mi file that contains a definition of the first frame and descriptors of the incremental changes from frame to frame. If you uncheck “Incremental (Single File)”, each frame is exported as a separate .mi file.
“Browse …”
Allows to specify the output file name.
Inside mental ray 
It would be interesting to know what percentage of MR users this is actually of any use to.
Your lack of visible development is slowly killing your product.
Thanks for your interest in mental ray and its integration in 3ds Max.
We are in year two of a turn-around. NVIDIA is now an extension of the Autodesk 3ds Max development and planning process.
3ds Max 2015 is the start, 3ds Max 2016 will have more, as will 3ds Max 2017 and beyond.
You might want to enroll the 3ds Max beta program to see the development being made there.
This is actually useful for quite a lot of our users (so Thank you!), many of them are students and new comers whom learn many things “on-demand” as they needed it. To use our new renderfarm (exa.io); they need to export to .mi files and you can’t imagine how many of them do NOT now how to do it.