Maya 2017 Batch Render Flags

[halfstone]

Using Maya 2017 Update 3 with Arnold v. 1.4.2.1, doing some command-line renders.  

When I use the "-im filename" flag, I get an error 

here's the string I'm using - 

Render -r arnold -ai:lve 1 -x 3840 -y 2160 -reg 0 1920 0 1080 -im topLeft.exr YP.ma > topLeft.txt

and the error: 

Invalid use of Maya Object "topLeft.exr"

Clearly I'm breaking up a large render into four regions.  Everything in the command works fine until I put the "im" flag in there.  Is this flag not supported in Arnold?  Is there another flag I can use for the filename?  Obviously, it won't work to call all four regions by the same name - they'll just overwrite each other.  

The project is set correctly; the renderer finds all necessary files and writes the finished file to the right place, but will not allow me to overwrite the name. 

I have tried leaving off the extension and quoting the name, but to no avail.  I've even put in the absolute pathname.  

I tried the same command on a mental ray render with the same error - is this no longer supported in mental ray either?  

I suppose I can copy/paste the Maya file four times and name it something different for each batch render, but that's a little silly ... 

Thanks

[Stephen.Blair · Accepted solution]

https://knowledge.autodesk.com/support/maya/troubleshooting/caas/sfdcarticles/sfdcarticles/Script-to...

[halfstone]

Thanks for this - sorry for the late-ish reply; I haven't had the chance to test it out at all but now that I have, it works just fine!