Corona saving layered EXR on render end

[maru]

I did manage to reproduce this, but only under very specific circumstances:
- You must be saving from the VFB> Save All (it does not happen when the files are automatically saved on render end)
- You must manually add all render elements to the list in the EXR save dialog
What happens then is:
- The beauty is saved in EXR format with all render elements stored inside it (can be found for example in Fusion, but not in PS)
- Each single render element is also saved in EXR format with all render elements stored inside it (again this can be found in Fusion)

So if the same behavior can be triggered when rendering via BB/DR, then I suppose this would be the culprit.
We will look into it further, and will see if the same happens with other renderers. If it only happens when using Corona's "Save all", then it would be a Corona-only issue. I can't test it right now.

[Frood]

Maru, I tested this with BB2019 and Max2020 finally. I used a simple scene with a single render element added in the RE tab, not touched afterwards and not manually added to the EXR output. Maybe the case you described is just a subset:

1. Scanline and EXR:

BB job A: Autoadd ON in output configuration when submitting the scene:
   1) BB server local setting autoadd on: 1 layered EXR written (beauty + RE)
   2) BB server local setting autoadd off: 1 layered EXR written (beauty + RE) plus 1 flat EXR (the render element)

BB job B: Autoadd OFF in output configuration when submitting the scene:
   1) BB server local setting autoadd on: 1 flat EXR (beauty only), NO render element at all
   2) BB server local setting autoadd off: 1 flat EXR written (beauty only) plus 1 flat EXR for the render element

---------------------

2. Scanline and CXR:

   4 times 1 flat CXR (Beauty only) plus 1 flat CXR (the render element). No Alpha.

---------------------

3. Corona and CXR:

   4 times 1 layered CXR written (Beauty + RE) plus 1 flat CXR (the render element)

---------------------

4. Corona and EXR:

BB job A: Autoadd ON in output configuration when submitting the scene:
   1) BB server local setting autoadd on: 1 layered EXR written (beauty + RE)
   2) BB server local setting autoadd off: 1 layered EXR written (beauty + RE) plus 1 flat EXR (the render element)

BB job B: Autoadd OFF in output configuration when submitting the scene:
   1) BB server local setting autoadd on:1 flat EXR (beauty only), NO render elements at all
   2) BB server local setting autoadd off:1 flat EXR written (beauty only) plus 1 flat EXR for the render element

You can see that Corona + EXR is exactly the same as Scanline + EXR, a weird Max issue - not bound to a specific renderer. And again you can also see the impact of local settings. Case B.1 is the reason for removing the script from here.That post is still valid for me, since I was able to reproduce it with the newest versions available. Only B.2 and A.1 are correct results, B.1 is data loss in the worst case and A.2 creates annoying additional render elements as Corona CXR always does ;)


Good Luck

[rowmanns]

You can see that Corona + EXR is exactly the same as Scanline + EXR, a weird Max issue - not bound to a specific renderer. And again you can also see the impact of local settings. Case B.1 is the reason for removing the script from here.That post is still valid for me, since I was able to reproduce it with the newest versions available. Only B.2 and A.1 are correct results, B.1 is data loss in the worst case and A.2 creates annoying additional render elements as Corona CXR always does ;)

Good Luck

Hey Frood,

Just to confirm by A.2 and B.1 you mean:

2) BB server local setting autoadd off: 1 layered EXR written (beauty + RE) plus 1 flat EXR (the render element)
and
1) BB server local setting autoadd on: 1 flat EXR (beauty only), NO render element at all

Thanks,

Rowan

[Frood]

you mean:

Yes, exactly.

Good Luck

[rowmanns]

Hi,

Okay so it looks like we can finally reproduce this in one way or another. It seems that there are some issues with saving EXR files.

With the help of Frood, we discovered that this is because 3ds Max saves the EXR saving settings locally on the machine and not in the scene.

This can lead to settings getting mixed up when rendering over a network with backburner. I have sent this over to Autodesk and I'm awaiting their response.

In the mean time, it might be best to set a pre-render script in the scene which sets the EXR file saving settings before each render commences. I hope this can be a suitable workaround for the time being.

I hope this information is useful.

Thanks,

Rowan

[zemmu]

Hi guys,
I have a similar problem.
Massive exr files BUT all the passes are unreadable.
Is there a way to fix the exr files so I can read them?

[Frood]

Looks like another issue, I would start a new thread for this in "I need help" with a zipped example exr as attachment.

Good Luck

[TomG]

Yes please on the new thread and example EXR - also though, they are unreadable in what software? (If native Photoshop, it's notoriously bad with EXRs, install the free EXR-IO and use that to open EXRs; if not Photoshop, do mention in the new thread what software it is you are using to open the EXRs).

[UsmanS]

was there any solution to this issue ?

[rowmanns]

Hi,

This issue was reported to Autodesk, unfortunately there is nothing we can do about this.

This is a possible workaround:

In the mean time, it might be best to set a pre-render script in the scene which sets the EXR file saving settings before each render commences. I hope this can be a suitable workaround for the time being.

Thanks,

Rowan

[UsmanS]

Can someone please make this script and post it here?

[Frood]

It is already attached here:

https://forum.corona-renderer.com/index.php?topic=25686.msg158408#msg158408

If you want to enable/ensure to have all render elements in one EXR, you have to uncomment the lines between "-- Switch autoadd on:" and "-- Switch autoadd off:" by removing the leading "--". Then use it as a prerender script.


Good Luck

[UsmanS]

Thanks for giving me that link, but I couldnt get it to work properly. I basically dont check the box in EXR settings "Automatically add/remove render elements from render dialog", so how do I set up that script so that it doesnt save all the render elements in each file and all files being same size at the end. I want to stay seperate with their original sizes

[Frood]

I'm not sure if I understand correctly. You do NOT want to have layered EXRs with all the render elements included, but "flat" EXRs for beauty and all render elements - a bunch of 32bit files with 1 layer? You would have to uncomment all lines after "-- Switch autoadd off:" instead. Please compare to the impact/results. Your case would be 4.B.2 (Corona and EXR -> Autoadd OFF -> Local settings autoadd off). Remember, you only may need this when doing any network rendering like submitting a job to Backburner (Corona DR is not affected).


Good Luck