Why is my Lumen unstable (see attached video)?

When I watch other people working with Lumen on YouTube, their viewport and their Lumen Overview looks pretty stable, but mine doesn’t. Is this normal? All three lumen views are just flickering and the lighting in the main viewport isn’t stable. See the back wall near the door in the video for example… the light just pulsates and even leaks slightly (probably because it doesn’t stabilize).

This is normal, nothing is wrong.

In areas that are directly lit, you’ll get stable lighting in the Lumen Scene. But in indirectly lit areas you’ll see this. The appearance has changed as the engine has gone through early access to today, but it’s always looked a bit wonky in indirectly lit areas.

You might be able to improve this somewhat (emphasis on somewhat) by increasing the Lumen Scene Lighting Quality setting in your post process volume (I believe the slider only goes up to 2, but if you type in numbers it can go all the way to 6). In general, it only really helps improve the quality of glossy reflections, GI won’t benefit much if at all.

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Same problem! I’ve tried this option but it doesn’t seem to get it working…

Ok, good to know my debug views are normal.

Regarding that pulsating light on the back wall, what I have found is that if I go to Rendering in Project Settings and change the Software Ray Tracing Mode from Detail Trace to Global Trace, then the pulsating goes away and the lighting looks pretty stable in the main view (the debug views still flicker the same but that doesn’t matter).

So this has me thinking that maybe the Detail Trace doesn’t have enough resolution or something on the meshes perhaps? Any ideas where I would look to try and increase this a little for the Detail Trace.

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