Render errors - dark blocks in 10% of image at 4505 vertical resolution

Development Cinematics & Media
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We are getting a dark bar on the right side of our renders when we exceed a certain resolution; (4505 horizontally). Here is an example image that we can legally share:

[Image Removed]

Although once we reduce the res by 10% the issue resolves. This looks similar to a screen space effect.

Currently our workaround is to reduce the render resolution by 10% and compensate in post. Attached is an example image you’ll see the right hand portion of the screen where the issue is occurring.

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Steps to Reproduce
render an image / scene. Review the result.

Windows 10

UE 5.5.3

NVIDIA A40-48Q

NVIDIA Driver Version: 553.62

CUDA Version: 12.4

3

Hi Tom,

Thanks for reaching out. At first glance, I can’t say what is going wrong here. Besides a screen-space artifact, I could also imagine the artifact being tied to our upscaling or post-processing pipeline, since it sounds like it is tied to resolution changes. So at this point, I need a little bit more information.

Please let me know what resolutions you are trying to render and if you are using any upscaling tech (TSR, DLSS, etc.)? If you use an upscaling solution, please let me know your settings. Have you also experimented with your post-process settings to see if any of those are causing this artifact?

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Hi Tom, What is the Screen Percentage set to? Try setting it to something 100 and see if that corrects the issue.

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Also, are you using a Post Process material?

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Hello,

Could you try capturing the scene with the error using DumpGPU while the scene is rendering and attach the output for us to look at? That would help us better identify the pass responsible.

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Hi Tom, Have you tried changing the Screen Percentage to 100% when you are rendering the 4k plates?

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Hey Tom,

Just circling back on this to see if your issues was resolved, and if so, how you guys went about fixing it. Thanks!

Michael

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Hi Tim, thanks very much for taking a look at the isue and getting back to me…

I’ve got some feedback from the user/crew:

Their 1st response:

we are rendering at 4506x3138. it seems to be tied to the horizontal resolution. so reducing the resolution horizontally by 10% fixed the problem. But we obviously would like to render full resolution.
We are not using DLSS. Adding it to the render settings (DLAA) did not change any thing.
We actually do not have anything much in terms of Post Processing settings But I have not been able to test that yet. Will look into it.

Then actually some further developments in the past 48hrs:

We were able to do some more tests. And The DLSS thing got me thinking. We were not using it before but I tried it and setting it to “quality” setting actually fixed the issue. “DLAA” which would actually be the go to setting for a rendering did not help, but as far as I understand the “quality” setting it down samples (some or all) G buffer passes and scales them up using Nvidia’s deep learning tech. So basically instead of reducing our render resolution and upscaling in nuke in comp we let UE handle it with maybe a added bonus of DL upscaling and about 10%-15% savings on render time. The images are slightly softer in direct comparison but neglectable.

It would still be interesting to follow up with Epic because this issues seems to pop up around the internet without any plausible fixes. Only compromises.

I hope that give some useful details, I can keep passing anything to the crew to update or try let me know
thanks again
Tom

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Hi Michael, no we’re not using a Post process material in the beauty render.