Serious lighting bug on external (web interface) render farm.

[JPeters]

Hi there,

I'd like to bring to your attention a rather serious lighting bug which happens on external (web interface) render farms. This bug manifests when single frames are rendered on multiple machines and what happens is that both Corona Sun *AND* Corona Sky (improved sky model but also other models in earlier versions) seemed to get decreased in strength.
We've experienced this bug in multiple Corona versions now and hoped it would be addressed in Version 6.0 but that still does not seem to be the case.

Since the lighting is different and the whole process of a render farm is to speed up the rendering process, this is quite the handicap.
The only viable solution at the moment is to, even if you only want to render one frame, create at least 2 frames in your scene so a single machine will render each frame. Rather then frames being split over multiple machines if you only render one.

Below I've attached two images showing what I mean which also contain the relevant information to the scene/situation.
It's an image showing the light mix of both the Sun and the Sky separately.

This happens with *ALL* scenes, newly created and old and in multiple versions of Corona (as it's been happening for a while).

Would it be possible for someone at your end to please look into this and potentially address the issue (or explain the solution) in a timely fashion?

Kind regards,

[Beanzvision]

Hi, Sorry to hear you're having these issues. I'm not able to reproduce it here on my end. Would you be able to share your test scene with us? If so, please use the 'save project with assets' option from Cinema when saving. You can use our private uploader to store your scene: https://corona-renderer.com/upload

Can you also tell me what OS you are running and the C4D version?

Thanks in advance!

[JPeters]

Hi Beanzvision,

Sure! The file is uploaded:
1600781687_Chocolat-Met.zip

Basically as an experiment we run that scene with 1 frame on the render far which splits it over multiple machines and we also run a copy with 2 frames which splits it on 2 machines (so one machine for each frame).

CinemaR21, Corona 6.0, MacOS Catalina 10.15.6 but the render farm consists of multiple MacOS versions including Mojave.

Let me know if you can find the solution.

Cheers,

[mmarcotic]

Hey JPeters,

we have been observing a pattern with lighting and team renders, are you using LightMix in those scenes? We're looking into such issues.

Thanks,
Jan

[JPeters]

Hi Jan,

I've asked my colleagues and they have the issues both with scenes that use light mix and without.
Hope this helps.

Cheers,
Joep

[BigAl3D]

Any chance this is the same long-lived issue with the Corona Camera Tag settings not being passed along to the clients? The workaround is to copy the settings from the tag, to the Basic Photographic Settings in the Render Settings. Then all is well.

[mmarcotic]

Any chance this is the same long-lived issue with the Corona Camera Tag settings not being passed along to the clients? The workaround is to copy the settings from the tag, to the Basic Photographic Settings in the Render Settings. Then all is well.

Very interesting, thanks for the workaround!!
Jan

[JPeters]

Any chance this is the same long-lived issue with the Corona Camera Tag settings not being passed along to the clients? The workaround is to copy the settings from the tag, to the Basic Photographic Settings in the Render Settings. Then all is well.

That is a good workaround but that only works if you don't have different settings for different frames right?

[mmarcotic]

Any chance this is the same long-lived issue with the Corona Camera Tag settings not being passed along to the clients? The workaround is to copy the settings from the tag, to the Basic Photographic Settings in the Render Settings. Then all is well.

That is a good workaround but that only works if you don't have different settings for different frames right?

You are probably correct, however, I received a build from the devs in which this issue is tackled, you should have it in your hands really soon.

Thanks,
Jan

[JPeters]

That would be great :)

[JPeters]

My mistake, not true.