Missing passes in the .exr-file

[hardrock_ram]

I am having a problem with render elements missing in the exr-file when I open them in Nuke.
I am using 3dsmax, Vray and Nuke. I am currently on versions 2016, 3.3.004 and 9.0v6 respectively, but this has been a problem a long time. I am also frequently using Deadline to manage the jobs. It is also the same both home and at work. Granted, I am the person who have configured computers and software at both places, so take it for what its worth.
I am using the render elements dialog box in 3dsmax, along with Vrays own frame buffer to render 32bit deep (as in deep images) .exr-images.

When I open the .exr-images in Nuke, it can happen that some channels are not listed, even though they are in the render elements list in 3dsmax. Other times they are listed, but completely black, even though I know they should contain something.
I have noticed that the problem is much bigger when I save, close and reopen 3dsmax, rather than render directly. VrayLightSelect is an element that has never worked for me if I don`t go straight to render after adding them. The same goes for mtlSelect.

The problem is restricted to a few "peripheral" elements like background, light select, reflecthighlightgloss and so on. The "core" elements like diffuse, GI, etc. are always fine.
I am using Deadline, but the problem is the same even if I render local.
I am also a pretty heavy user of render elements. I often fill the .exr with probably 50-100 seperate channels\elements. These days I usually render out deep images, but the problem doesn`t change if I turn deep off.

Hope you can help me
Regards

[tashko.zashev]

Hi,

Would it be possible to send us some file to support@chaosgroup.com ? One of the scenes (could be only small part of it) you have problems with and one EXR file.

I assume the problem doesn't occur if you render with Separate render channels to EXR ?

[joconnell]

I've often found with channels like multimatte where I use multiple different multimatte elements, if I leave them with their default names, one multimatte will overwrite the data of the other. Try taking one of your bad renders and renaming the element's name (not it's output filename) to something other than the default so that no two render elements share the same name. See if it behaves for you!

[hardrock_ram]

Hi,

Would it be possible to send us some file to support@chaosgroup.com ? One of the scenes (could be only small part of it) you have problems with and one EXR file.

I assume the problem doesn't occur if you render with Separate render channels to EXR ?

Sure, where can I send it?
I have not tried with seperate channels to exr, so let me do that first

[hardrock_ram]

I've often found with channels like multimatte where I use multiple different multimatte elements, if I leave them with their default names, one multimatte will overwrite the data of the other. Try taking one of your bad renders and renaming the element's name (not it's output filename) to something other than the default so that no two render elements share the same name. See if it behaves for you!

No, the problem occurs just as well in channels I`ve only got one of. For example, a job I am rendering right now lacks the background pass, even though it is added.

[tashko.zashev]

OK then, please send us the scene file to support@chaosgroup.com for a further troubleshoot.
Thank you in advance.

[hardrock_ram]

OK then, please send us the scene file to support@chaosgroup.com for a further troubleshoot.
Thank you in advance.

Can I send you that big files over email? The scene file is around 200mb and the .exr-file is probably 100mb.

[tashko.zashev]

No, its too big. Please contact us via our support mail ( support at chaosgroup.com ) and we will provide you with our FTP server login information in order to upload the file there.
Don't forget to add this forum thread as a note.

[sylk]

Hi, any news on this topic? We are experiencing some weird stuff too. Sometimes (often with projects with multiple render elements) one frame of a certain render element doesn't get saved. So we are rendering a sequence and when we are compositing everything together we notice that one frame of a certain render element is missing. Not 100% sure but I don't think that the RGBcolor ever has been the problem. MultiMatte and LightSelect I am sure of and i think there have been other elements too.

Last time it happened to me it was the LightSelect-element that had 2 frames missing. I was saving Deep so it was a multichannel exr. But I have also experienced this when saving separate elements as separate exrs.

The solution is to re-render and hold your breath. Not ideal.

[hardrock_ram]

No, I haven`t rendered anything big lately, so I kind of forgot about this post.
However, I have never experienced that only one frame of a certain element was missing. It`s always the full sequence (of an element).
As I mentioned in my first post, this is something I learned to live with.
As long as I send the render to the renderfarm in the same 3dsmax session that I added the element to the render elements list, it is very rarely a problem. The problem arises when I add elements to the list,
save and close 3dsmax, and then reopen. If I then try to render, I can almost guarantee that the individual light passes will come out black. But if clear the render elements list and set it up again, the it is almost never a problem.

This bug was actually one of the main reasons I wrote a script to make handling of everything "administrative" in regards to rendering much more automatic and simple. It makes it much less annoying when I have to clear the render elements list and set it up again. When I add the "save setup" feature in the script the circle should be complete :P.

The last V-Ray version I rendered with, was 3.3.004

[Svetlozar Draganov]

It would be interesting if this issue exists in the latest 3.40.01.
If it is still there it would be a good idea to troubleshoot and fix it but I don't know how we could reproduce the issue into our environment?
Can you send us(if haven't already) some scenes and instructions what actions to perform in order to replicate the issue in the exact same way?

[hardrock_ram]

I am on vacation right now, but I have a render job coming up not long after I get back. The files shouldn`t be to big either ...

[hardrock_ram]

I got an example file, and I have sent a mail to support regaring this issue.