Saving a single EXR with several render elements - how ? (frustrating / confusing).

I’m having serious issues getting my head around how to save a multi-Render Element EXR.

Usually I render on my own single machine, via VFB, and save an EXR using the save button on VFB. No problem.

But… when I want to save a multi-Render Element EXR either using Backburner, or simply via the Render Setup Dialog box, it’s a bit hit and miss whether I get all render-element channels (usually I get just a single layer RGBA channel within my EXR).

So,

In Render Dialog box, there are two places I see how to save EXR files, one under the Common tab, and the other under Frame Buffer section (under the V-Ray tab).

If I save via the “V-Ray raw image file” option, there I can save as a .vrimg file and import that back into VFB and save as an EXR (longwinded but does the trick).

But if I save via the “V-Ray raw image file” option, there I can save as an EXR, but that doesn’t do that… the image gets saved as a .vrimg AND a .vrimgsl.

So why is the EXR option there at all ?

If I don’t do any of the above but use the “Save Files” under the “Common” tab, there I an specify EXR but must choose “Setup” to Add the Render Element as thus;

But this doesn’t work ?

And it definitely doesn’t work using Backburner (which I’d like to use).

Please, can someone give me a definitive explanation how to save multi-render elements EXR files ??

Many thanks.

Saving using the “V-Ray raw image file” option is all we use and that works just fine. Just enter a filename with .exr extension and it does the rest, no?