Topic: Light level inside closed area

[Tom Aren]

Hello, I was trying out a few different scenarios in Lumion.
There is something that I cannot resolve.

Why is the brightness inside a completely closed box not at zero? ? In other words - why is it not dark inside a house without any window and no lightsource insode of the house?)
If I am inside a box without any "windows, the sunlight still seems to pass through. Is there any thread with detailed information on this?

There's another thing I'd like to know and I guess that the solution is related to my other problem since it's the opposite of the question.
I tried to follow the instructions In this thread http://forum.lumion3d.com/general-discussion/custom-backgrounds/msg49413/?topicseen#msg49413  : 

The lightlevel inside the Skybox is not uniform. I mean, it looks like it has full brightness on one side... that's the way it's supposed to be. But the other half of the dome looks like it is a shadow. How can this be resolved?
I tried to apply the "roughness" settings inside of Max, but this did not change the result.

Thank you.

[peterm]

Hi Tom

In Lumion all surfaces receive some lighting from the Sun (and also Sky and Clouds).  If you want to control the amount of lighting then you would reduce for example Sun Brightness down to 0, and all settings that affect lighting for the Cloud Effect eg Sky Brightness to 0 (see closed room pic 2).

All materials of surfaces have default levels of lighting so that they are visible.  If you look at the material properties of a surface that has been made a Standard Material you can adjust those down to 0 to remove all further lighting for example Brightness (see pic1).  Note Emissiveness is set to a default of 0 and is used (along with Overbright) to increase lighting above normal conditions.


I added a semi-hemisphere and set the lowest lighting and material settings and it's pure dark, so yes, knowing the above should work for you.

Note in Build Mode you will see a real-time approximation of the final result.  You would need to add effects such as Sun Effect and Cloud Effect to Photo Mode or Movie Mode and change the level of lighting there, then see in Preview and as rendered.

[Tom Aren]

Thank you peterm, I think I got it.    The way lighting seems to work in Lumion makes sense to me considering the field it is mostly used for - on the other hand it may be quite hard to get the expected result under certain circumstances. 

In your answer you wrote "I added a hemisphere...."
Did you mean you attached a scene file to this post? Because I didn't see it.

Thanks again ; )

[peterm]

No, I just meant I tested using a semi-hemisphere to follow the post you mentioned.