Black rectangles in saved images

[OleksandrV]

Hello!
After transfering to corona 11 we started noticing black rectangles in saved images, in frame buffer everything looks fine though.
It happens both in the VFB lightmix and multimap enviorment saved images, other render elements as zdepth or wirecolor are fine.
When rendering animation rectangle may apeare and stay on the same place for each next frame rendered, sometimes it can get bigger.
Also doesnt matter on the size of the output, it happens in 4k or fullhd.

After instaling hotfix this problem stopped apearing on some of the computers, some still have it, but it still constantly shows on the slower ones.

I have attached cutout from the recent render below
Is there any solution to this problem?

[Avi]

It seems like you are getting a NAN issue. Do you get a NAN warning in the Corona log?

[OleksandrV]

Indeed i see NaN error
Is there a way to fix it?

[alexyork]

We've been getting something like this too - random black rectangles, but it's specifically only in the alpha channel of the rendered file (in our case EXRs), not the actual diffuse/beauty etc.

I'm not sure if this is the same thing as OP, but I can't check if there are NAN errors as this was on a bunch of frames rendered via Pulze RM. All I can say is that in a sequence of 500 frames there were 5 x "broken" EXRs with a rectangular (varying!) sized hole in the alpha, usually somewhere along the bottom right (but not always). When re-rendering them they were fine. This was across multiple machines, nothing machine-specific.

I can't send over any files due to NDA, sorry.

[Avi]

We are aware of the "NaN" issue in Corona 11 Hotfix 1. We can currently offer the following options to tackle it:

If possible, downgrade to Corona 10 Hotfix 3 by downloading and installing it from https://corona-renderer.com/download/old and re-render your scene using this version. Unfortunately, this may not be a valid solution depending on what exact features you are using. Corona 11 features will not be rendered in Corona 10.

Install the newest Corona 12 daily build - https://forum.corona-renderer.com/index.php?topic=41598.0 - please make sure you save a backup of your scene before opening it in a daily build as it may be unstable and may even damage scene files! One possible workflow here would be creating your scene with Corona 11 and only rendering the final shots with a Corona 12 daily build.

We are also planning to release Corona 11 Hotfix 2 soon, which will include the NaN fix. Sorry for this inconvenience!

[alexyork]

Thanks for the update, and fixing an issue like this with a hotfix for the current main build is really appreciated.

[OleksandrV]

Thanks for the reply and fixes.
Can you please say aprox time until hotfix 2? Is it couple of months or weeks? so i now if its reasonable to switch our studio back to corona 10

[TomG]

Build is going through QA. If all goes well, we hope to see this released sometime next week.

[Frood]

This should at least ought to been some announcement in the forum. Having knowledge of this bug, not publishing it, letting customers scratch their head and having a bad time when producing output appears like bad product management to me. I'm not reclaiming the public bug tracker we once had, but be more verbose please.


Good Luck

[TomG]

We didn't make it for last week, as the QA process uncovered an issue, but the new HF is now out as of today. https://corona-renderer.com/download

[Pooya Madani]

Hi guys,

I have been experiencing the same issue for a while. It happened randomly. In the render frame everything is OK but when the render is saved, it has a random sized black rectangle area. It doesn't happen if I save the render as CXR, so I had to save CXR and use copy/paste to photoshop and save the image. I just installed the new hotfix 2, let's see if it solved the issue.

Regards

[maru]

Hi guys,

I have been experiencing the same issue for a while. It happened randomly. In the render frame everything is OK but when the render is saved, it has a random sized black rectangle area. It doesn't happen if I save the render as CXR, so I had to save CXR and use copy/paste to photoshop and save the image. I just installed the new hotfix 2, let's see if it solved the issue.

Regards

This should be solved in V11 Hotfix2. If it's still happening there, please contact us at https://support.chaos.com/hc/en-us/requests/new