Indirect Illumination inconsistent between Edit and Play

Essentially whenever I Play the scene, the indirect lighting appears to disable/reduce significantly compared to Edit mode.

EDIT MODE

PLAY MODE

General scene composition:

  • Lumen
  • Directional light, exp height fog, sky atmo+vol clouds (though camera is far above them). Volumetrics enabled

I’ve tried adjusting just about every setting around the directional light, height fog, shadows, volumetrics/contribution. The only thing I can discern is if in Edit mode, I can achieve the reduced bounce/indirect lighting I see in Play be dropping the "Indirect Lighting Intensity from 1.0 to 0.0. But if I play, the value at 1.0 in Play looks like 0.0 in Edit. And If I try and increase the value in Play I just get stronger lighting impact but not so much with bounces.

PLAY + BOOSTED "Indirect Lighting Intensity"

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The boosted intensity looks wrong because of that brigher field near the bottom of the shadow in the bottom left.

Are you sure the difference between play/edit isn’t just exposure settings / eye adaptation?

I’ve confirmed the following:

  • Issue still persists with auto exposure set with constant 1.0 min/max
  • Created a new world with the typical dir light+sky atmo+clouds and only the above foreground geometry and was also able to reproduce
  • Also tried several variations of the above geometry - separating walls/ceiling/floor into different meshes, removing window materials so they’re only holes, all produced same results.

One additional thing I’ve noticed. I actually got the Edit viewer to look the same as the darkened Play visual. It looks like this has something to do with maybe a light baking bug. I have only dynamic lumen enabled, all baking disabled/force no precompute enabled. In Edit mode if I make a change to the static geometry (toggle mesh distance field, any build param) it reverts to the darker look. But then if I click Build > All Levels it updates to the first visual that looks correct. I then also see the following in Lighting StaticMesh Info

Could there be something weird happening around the configuration state for lighting? I would think baking wouldn’t alter the image at all with Lumen/full dynamic?