Lets make Lightmass EPIC (and understandable)

I’ve done scenes with .9, 100, 10, .66 and it took round 7 hours on 2 machines. Not too bad! Under 10 hours is ok-ish but over 10 hours it’s a bit long. Koola might use a bigger renderfarm who knows!

See post #8.

Thanks for sharing your results koola.

NumHemisphereSamples is how many rays will be traced at the base level of refinement for the final gather, which means direct shadowing for a skylight. IndirectLightingQuality already scales NumHemisphereSamples. So those settings are equivalent to massive brute force, something like 16k rays before adaptive sampling even kicks in, which explains the render times.

Personally I won’t spend over 20 minutes building lighting for such a small scene but I know you guys are going for maximum quality.

Most people serious about arch-viz probably have access to a decent render-farm. Even if it takes 10 hours for the final bake, this isn’t a big problem as long as it’s predictable in the end!


Is it possible to give us something like this? In Modo for example if there is noise I know to increase the samples in the lights. So, for us non technical people can we get an over view like.
Blotchy try x, x and x
Light leaks, increase lightmap rez and x

All this tech talk makes my head spin. Hahahaha

There you go!

Oh! I’m going to check those at home, getting lots of weird issues in my level.

Thanks for sharing you guys. :smiley:

You are my hero, I wasted 2 days searching for a solution.

Cool, that helps thanks.

alright! I’ve been waiting this for type of thread- now that we got the heavy hitters in the line up makes it even better. I will post my results as well.

Again, I don’t know what I’m doing :slight_smile:
There is certainly a better and faster solution.

I hope you have 56 000 cpu cores available or brace yourself!

Lol, for my scene I don’t need super quality, just don’t be full of splotches everywhere.

Screenshot of my scene before ini change:

Screenshot of my scene after:

Build lights 4 hours in a AMD fx6300.

Static Lighting Level Scale : 0.7
Num Indirect Lighting Bounces : 100
Indirect Lighting Quality : 10
Indirect Lighting Smoothness : 0.7
And in the BaseLightmass.ini :

I haven’t more screenshot of before vs after, but had splotches like that everywhere, and now is a lot more clean, for me, this balance time vs quality is ok, I know isn’t perfect, but good enough:

I have a question. If the original value was 8 in the .ini for NumHemisphereSamplesScale why the jump to 100? Did you guys try 16, 32, 64 etc. first?

I notice that, for really nice “contact shadows” see Raghu post for reference, check the second picture the indirect lighting smoothness needs to be around 0.4-0.7, it really depends on the scene ( I’m using bounce cards ), since that value can mess up the entire scene.

Do you use any alternative tricks to achieve those soft shadows?

So, I am wondering. What is smarter. Light your scene with only a skylight and a directional light or use the bounce card + spotlight technique? Which gives better results?

From what I’ve seen if you’re using only sunlight and skylight, in order to have proper indirect lighting inside an apartment for example, you should increase the Indirect light intensity on the light itself, but that for me seems to be the main problem with light leaks, so I usually stick with bounce cards.

The bounce card technique is used widely on Max/Maya/Vray/other renderer because it gives better results and you can control much better the indirect lighting on an area.
I also use a bit of boost on the lightmass settings to increase the overall brightness on the scene…but also using the post process Indirect lighting gives you good results ( in realtime, which is nice ).

Sounds good :slight_smile: I will give it a try!

Good findings Rafael!

So, better not use fake lighting with bounce cards? Only sun and sky? I am afraid that its not enough to light a whole house only through the windows …