Since Ray Tracing causes performance issues and also makes the backsides of trees very dark, So I unchecked the Visible in Ray Tracing option for all trees, but this makes the trees very bright, as if they are missing shadows. How do I fix this? Thanks for any tips
Anybody help?
Your trees are bright because you removed it from ray tracing, so its not calculating where to get its shadow details from.
What you can do is use HDRI, and then you won’t have problem with it but if its an open environment like when your camera or character moves around then your HDRI wont look good.
Another thing which you can do is select your Directional light and change your shadow method from ray tracing to disable, it would be less accurate shadows but it will solve your performance issue.
Also check if the megalights is using raytracing or virtual shadows, choosing between these two can also vary in performance.
Thanks for your reply. My project uses a lot of nanite assets, so I enabled Virtual Shadow Maps. I tried disabling Cast Ray Traced Shadows but the trees didn’t change.
If you are using HWRT for Lumen you are removing the trees from the Lumen scene. Its possible that is contributing to this as well.
Thanks, I just tried turning off HWRT and for non-ray traced trees it improved. But for other ray traced Actors they look really bad.
Yes that is because Lumen without HWRT is only guessing the bounce lighting and shadows as it does not use the GPU completely, as much as i understand because i too was confused before.
But with HWRT turned ON it is now using the ray tracing capabilities of your GPU, so it gives you almost accurate lighting and shadows, it won’t be perfect but it is still close enough to path tracing which gives you accurate rendering just like any another renderers out there like v-ray, corona etc.
HWRT turned OFF will give you more performance as it is using less GPU power but with less accurate lighting.
HWRT turned ON will give you less performance as it is using more GPU power but with more accurate lighting.
I hope this clears your doubts between hardware and software raytracing.
Now coming to your trees, sometimes there can also be shader problem and not lighting problem, like not using proper blend mode or not using surface translucency volume.
So i would recommend download any of the quixel trees assets and try to understand how that shader is made or atleast check out what blend mode and surace shading method is used in them and try to replicate it on your trees.
Is there a way to force software ray tracing for trees when HWRT enabled?
I think the thing that you did that turning OFF visible in raytracing does the same thing but other than that sorry man haven’t tried anything like that.
I think they are different, you can see the two trees I marked with red boxes have different colors.
Note: Visible In Raytracing is turned off for both trees
Ok so I’ll have to try this thing in my free time, if i find a solution I’ll do reply but if i don’t then do understand that i didn’t find any solution. 
Anyway, thank you
No, you can’t selectively SWRT, unfortunately.
How about converting your trees to nanite and use virtual shadow maps.
In Unreal fest they showed about better support for nanite foliage and shadows and stuff, I’m using 5.5 at the moment so can’t confirm any improvement by this method.
Since i see you are working in 5.6 maybe try doing something that Unreal showcased in the fest.
Is this the video you’re talking about?Nanite for Artists | GDC 2024
No this one is from last year, i was talking about Unreal Fest that was showcased this month.
there are multiple livestreams, so i would recommend to check all of them, no need to watch complete livestreams just watch it in fast forward otherwise it would take hours, maybe you’ll find something