Why? I played with world Lightmass, sittings of the lighting source and another stuff
Now, I have those result.
But, right wall so dark, and in different places I have light leaks
and it is additional barrier between light scene
brightens of light 3.14, I will try make meshes larger
make your meshes thicker and overlap more. also your light looks extremly bright!?
ok, can you have a look here: A new, community-hosted Unreal Engine Wiki - Announcements - Unreal Engine Forums
light bleeding happens quite a lot with lot of different causes 
if you like to share your project I can have a look into it. in the past I got it solved with adding thickness and overlapping. for example block it with additional cubes from the outside to try it quick n dirty
it is did not give any result
Hi!
I have to disagree: overlapping walls and not corner snapped will highly possible cause these kind of leaks!!
Yes, your walls should have thickness (15- 20 cm)…
We need more information about your scene: what lights are you using to light up the scene, what lgihtmap resolution you have on your meshes… if you have importance volume in the scene… post process also…
Right now your lightmass settings are VERY low!! If you want better /archviz/ results, you’ll nedd to go a lot higher…
Thanks for help! For me helped 4th method
Thanks! For me helped 4th method
A few suggestions:
- Move the directional light out of the area of the depicted hallway. Currently it is immediately above the ceiling and inside the doorway.
- Change the directional light’s Environment Intensity to 0, even though the color is black and invisible (0 alpha). It could be still generating light bounces from the outside skysphere / environment and contributing to the light leaks.
- Check post process volume settings, especially under Rendering Features. What is enabled (checked)? What are the auto exposure settings, even if they’re disabled? Modify those to decrease exposure. Decrease global illumination, and in Light Propagation Volume, decrease intensities and occlusion to see how it affects that scene. If it causes the light leaks to get worse, then increase occlusion and modify bias settings to see if it reduces or removes the leaks. So in keeping with this, ensure the camera is viewing the hallway while tweaking. And build lighting only for each change or few changes.
- This is a last resort in a way. Go to World Settings, change the settings for volumetric lightmap. Decrease detail cell size by as much as half or a bit more, increase memory brick size to as high as double the current value but not more, and try tweaking the spherical harmonic setting (default is .003, so increase it to UP TO 0.2 or 0.3 and see if it removes those lines or leaks). This is a last resort because it really shouldn’t have to be changed from the default, and can affect the entire level or other areas more dramatically if done to the extreme.
I really appreciate your attempt. Keep us up to date with such amazing posts.