Hi, I have only recently started using UE4 and I’ve come across an issue that I cannot figure out.
I’m having a problem with the lighting of my level after I build the lighting. It suddenly becomes super bright for some reason. It’s probably super obvious to some, but I haven’t been able to find a solution any where.
Below are before and after screen shots.
In case you did not know already: In your screenshots is this little icon ‘Lit’ in the top left corner menu. there you can switch between different lighting. That doesn’t solve your problem but with that you can maybe find out more about lighting. This scene seems quite complex to me. Estimated 20 Light sources, you could turn them on/off ingame to make it dynamic, the lower scene looks quiet static to me. I know, it is not really an answer, just a comment.
Yes, I’ve been looking at those. But I must admit I’m new to the engine and don’t really know what they are all used for yet. The thing is I’ve tried removing all the lighting altogether, making the entire level complete darkness, and still when I do a build everything turns bright. It’s as if the level goes into unlit mode and doesn’t want to change.
So now I’m convinced it has nothing to do with the lighting I’ve placed in there, but to do with building itself.
I have a feeling this could be a bug.
The lighting in the bottom scene is totally blown out, but it is certainly still lit, it’s not unlit. We appear to be suffering from the same problem, which appears to be related to this other problem:
We had the problem where the post process settings were not working as described in this thread. Following these instructions does resolve the post processing issue, however it would seem it also totally breaks the lighting, causing us very similar results to the image above. Our night scene is lit up brighter than day right now.
Hello ambershee,
Quick question, but do you have a lightmass importance volume in your scene? The issue the user was having in the post you linked was a bit different than one you were experiencing and if you followed those steps, you reset your entire scene to a default state. This could have gotten rid of your LMIV (Lightmass Importance Volume) and you Global Post Process volume. Check to make sure you also have a Dominant Light in your scene as well.
Thanks,
Hi Andrew, thanks for the quick response.
We’ve followed the post process steps again, then taken a look at our lighting setup. We do still have our lightmass importance volume, and it would seem none of our lighting settings have changed. We had a fiddle and disabled our directional light (unticked affects world), and mysteriously, lighting is still completely blown out.
If we save the level and quit, then restart and reopen the level, our post process is broken again, but the lighting is working as intended.
This is almost certainly a bug, I think.
We’re in build 4.5.1.
Ok so after saving and re-opening, go into your post process volume. Be sure the Unbound check box is checked so it applies to your whole scene. This also seems like it could be an auto-exposure issue. Try setting these values to match the image.
Hi Andrew,
Neither of these help the problem - the film / scene colour settings in the post process volume simply don’t work until we try the ‘fix’ in the other thread. Other settings (e.g. Depth of Field) work perfectly normally.
After the ‘fix’, lighting is completely washed out but post processing does work.
After saving and quitting, then reopening the editor and map, everything is back the way it was before we started (post process is broken as described, but lighting is back to normal).
Ok well in that case, take all the lights in your scene, duplicate them and delete the original. Rebuild and see if that fixes your issue. If not, would you mind sending me your project so I can take a look at it? It doesn’t seem to be too large so you should be able to just .zip it up and post it in dropbox.
Hi Andrew,
The problem still persists. I suspect the lighting may be appearing to be completely blown out as post processing is broken.
The original post isn’t ours, we just seem to have a very similar problem - our project is pretty large (over 25GB), so it’s pretty hard to distribute. I’ll take some time to see if we can reproduce the problem on a small test map, though we may not be able to get that done now until tomorrow as it’s coming to the end of our working day.
Edit: We can confirm that the setting is entirely isolated to our specific project, but we’re still clueless as to the cause.
Sounds good, I am glad to hear you are narrowing it down and troubleshooting yourself as well 
we always encourage our users to do exactly that. Narrow down the issue to see if they cannot find the exact problem.
Yes let me know what you discover!
I believe it is a issue with the ‘Eye Adaptation’ post process. It seems very broken and I’ve heard a number of people griping about it. Deffo’ needs to be looked at by the engine team. Included two screenshots to show the difference. Elsewhere in my map the problem is even more exaggerated.
Eye adaptation translates to the Auto Exposure settings set in your Post Process Volume. Do me a favor and change the settings as mentioned earlier in the image I posted about Auto Exposure. Then toggle the eye adaptation off and on to see if you notice a difference there?
One question also when did this problem start occurring? Did you recently convert this project?
Hi, OP here. I don’t have a Post Process Volume in my project, just point lights, spotlights and emitters. I have literally started using this a week ago, so I don’t know what any of what you mentioned means. I did click ‘Show’ in the viewport and unchecked ‘eye adaptation’, but it didn’t make it look anything like how it was before the build.
I am literally so new to this I wouldn’t know what to check or troubleshoot.
Yup that worked. Thanks for your help!
Our problem is indeed being caused by Eye Adaptation - I’ve decided to just disable it by default in the engine core to prevent any issues in future.
Thanks everyone!
Hi! This hasn’t been resolved for me and have no clue as to why it is happening. I don’t have a Lightmass Importance Volume or a Post Process Volume in my project, so the points mentioned earlier don’t really appoly to me.
What I’ll do is apply both of these to the entire scene and see if I get any improvements.
Edit: Nope. =( I added the volumes and did all the tweaks suggested, but still get the same results. Even unchecking eye adaptation under Show>Post Processing in the viewport makes no difference to my scene.
When you added the volumes did you sent their bounding boxes around your level, or did you just place them in your scene without resizing?
Hi Andrew, thanks for getting back to me. When I added both volumes I did resize them to consume the entire level. Here’s a screen grab:
There are a few more suggestions I can think of to fix your issue. I do want to re-iterate your issue to make sure how to fix it. You are still experiencing the ‘washed out’ look similar to the second picture you posted? This image seems to be like the first one you sent on your post which is why I ask.
Either way there are a few things you can try aside from the suggestions I have made already.Firstly you can add a Skylight into your scene. The Skylight serves as an ambient light fill which can have a color applied to it. When you add this Skylight, change the color to a dark grey or even black. This will darken the ambient lighting in your scene.
Similar to this, within the ‘World Settings’ tab, you can change the ‘Environment Color’ to a dark gray or black. Keep in mind however, this will change the look of your entire world instead of just the the ambient fill light, like the ‘Skylight.’
White Environment Color
Black Environment Color
I hope one of these suggested fixes resolves your issue.
Thanks,
