Hi there, has anyone figured out how to increase the distance which lumen will render?
Under Show/Visualise/Lumen Global Illumination I can see a clear line where lumen stops.
I’ve messed around with all the r.lumenscene.distantscene commands but nothing has affected it unfortunately.
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Have you tried:
r.Lumen.ScreenProbeGather.Temporal.DistanceThreshold = 850
no luck unfortunately 
It looks like r.Lumen.ScreenProbeGather.Temporal is only meant to reduce the flickering of the screenprobe gather result. Going to mess around with some other r.Lumen.ScreenProbeGather. commands.
It may be that I’m just hitting a hard limitation of lumen though.
Has the same issues. Lumen works at close distance. But if I move camera too far, some of the GI rays disappear. Even with low fov, so geometry is still huge enough based on screen size.
I’ve tried increasing “Lumen Scene View Distance”, but seems it does not affect anything.
I also tried the command from previous post, did not help either…
Did anyone find a solution?
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yup, lumen distances values in post process volumes can’t change anything, so what’s the point of their existence?
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Was there ever a solution found for this?
Context: I’m rendering high-res screenshots from a top-down view to be used as map in a VirtualTableTop game. Since it’s screenshots, performance essentially doesn’t matter for me, I just need max possible quality.
No solution that I’ve found 
For what you need though maybe you could use ray tracing or path tracing, will look much better than any lumen solution 
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That is definitely true. Big thing: tiled rendering is not very functional for lumen at the moment, and it will have errors/inconsistencies like the ones you may be experiencing. If you need maximum quality and perf. is meaningless, use the path-tracer. It will yield the absolute best results.
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for the highest quality lumen, go lumen.screenprobegather.referencemode 1. This disables all lumen optimizations and cranks the sample count up wildly, in my experience it’s essentially PT-level quality for diffuse lighting at a still-interactable frame rate.
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Thanks, I managed to successfully switch my pipeline to use PathTracing, including tiled rendering. Required a lot of other switching around as well, but it works now (at a prototype state)
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Did you try PPV,
Lumen Global Illumination
Luman Scene View Distance: max value, together with,
Max Trace Distance: max value?
When I do, I can see changes.
Does anyone know if this was fixed? Looks like PPV and cvars do nothing to push out lumen in 5.2
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Also looking for an answer for this. Did you found a solution already?
The following worked for me in my use case:
- Enable “Use Hardware Ray Tracing” in project settings. Restart if required.
- These console commands:
r.LumenScene.FarField 1
r.RayTracing.Culling.Radius 100000 (couldn’t go beyond this number)
- Extras:
r.LumenScene.FarField.FarFieldDitherScale 10000
(helps soften the edge of where lumen reflections kick in)
r.Lumen.Reflections.ScreenTraces 0
(gets rid of the jarring transition between lumen and screen scace reflections, which can look quite different from each other)
Enable “Hit lighting for Reflections” in Ray Lighting Mode under Lumen in Project Settings. (produces more accurate representation for reflections in the Lumen scene)
Hope the above helps, please add to this if more is discovered as I really struggled. 
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really helpful , i don’t know how many time i search a cvar for lumen distance i tought finally it was hardcoded into the engine. thanks a lot it was the last cvar i needed, really helpful.
I could go over 100000, and this did the trick
r.RayTracing.Culling.Radius 1000000
r.LumenScene.FarField.FarFieldDitherScale 100000
Thank you!
Huh, that’s really interesting. My understanding of lumen was that the lumen scene included both the instances that make up the geometry (SDFs, RT proxies, RT streamed meshes) and the surface cache parameterization. If this RT-specific setting made a difference, does that mean that the geometry information is being managed seperately from the lumen scene?
This is just personal curiosity, I wasn’t aware lumen worked that way.
Good question, I wouldn´t know how to respond to that.
You are a legend. Thank you!
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