Archviz with Spot Lights Only

From most of the videos I’ve watched or articles I’ve read about archviz in UE4, most of them involve some sort of skylight and directional light. I’m working on a visualization of a theatre room which has no windows or any way for exterior lights to penetrate. I’m only lighting the scene with spot lights. Are there some special considerations or variable parameters for this lighting scenario that I should take into account?

I’m also getting a weird banding issue on walls when static spot lights are pointing on it. They go away with stationary lights, but the 4 stationary lights restriction (unless you turn off shadows) makes it difficult to light a whole room with only 4 stationary lights. I’m also still getting some other artifacting with static lights (banding, black splotches, jaggy shadows) even with the settings below.

  • I’ve ramped up “Indirect Lighting Scale” for the spot lights.

  • Made sure all the lightmaps are green or above in density.

  • Made sure the interior walls take up most the UV space when unwrapping it.

  • World Settings are:

    • Static Lighting Level Scale: 0.1 (Using Static Lighting x Indirect Lighting Quality = 1)
    • Num Indirect Lighting Bounces: 50
    • Num Skylight Bounces: 1 (No Skylight influence on scene)
    • Indirect Lighting Quality: 10 (Using Static Lighting x Indirect Lighting Quality = 1)
    • Indirect Lighting Smoothness: 1
  • I’m using the GPU baker, but I’ve also used the CPU baker with NumDirectPhotonsScale as 4, 8, then 100.

  • I’m building lights on “High” quality

Playing with Shadow Bias parameter can help with banding issue. And if you want more indirect lighting i suggest using a white material for surfaces getting directly lit while baking and change it back to their own materials afterwards.You can also increase Global Illumination Intensity in post process volume after building the lights. And since you said theatre i’m guessing the seats in the back and middle end up too dark, so make sure you have reflection capture actors as they help capture the light from lit areas. If that’s not enough you can also experiment with capturing a cubemap of the theatre and using that render target for post process ambient lighting.
If you still have issues feel free to post some screenshots.

Hi!

I don’t see why would it be different… you have light sources…
If you’re using the GPU baker you don’t really have much control!! …but I would avoid “forcing” the lights “artificially”: they usually just cause problems or fake/unrealistic lighting…

Green lightmaps for archviz scenes are usually too low… I guess this is one of the reasons you get blocky shadows…
Number of indirect bounces 50: no point! After 10 it’s kind of random and unnecessary. I’d stick with 5-10
If you keep your smoothness 1 you’ll lose all your detailed lighting mostly in contact shadows! I’d go with 0.6
Are you using portals + lightmassimportancevolume?
Any postprocessing?
Are you using planes as walls or full 3d meshes? Are they face or corner/edge snapped?
…some screenshots would be helpful! :wink: