Help with getting good result...

[sarford]

Hi guys,

I'm trying my hand at this interior but I have a hard time to get some good results.
I get all these strange light-leaks everywhere, even though the meshes are watertight.
When I switch on path-tracing in the FG tab the light-leaks are gone but also my contact shadows on the stuff on the table.
I've set the Spatial Tolerance very low to get some shadowing in tight spots as seen in the cigarette pack.
There are 10,000,000 photons fired into the scene.

I am at a loss, don't know what the problem is I'm seeing here and how to solve it.
Can anybody help me with this?

Cheers, Simon

ps: There are no shaders used in this scene, just a basic white LW material, no AA shaders also.

[jure]

Whenever you get light leaks the problem is in photon map. Can you render out photon estimate - precomputed and show your photon map settings? Also, did you check out photon map tutorial on wiki?

[Janusz Biela]

Ok there is solution for You
1. For that room is enough 500.000 photons
2. please turn ON PATH (the best setup is PATH 1 and 50-100%)
3. Spatial tolerance is too small! Is enough 0.07
4. Don`t use Brightness/Density.

[sarford]

Hi Jure and Januzsz,

Thank you both for helping me on this project.

I did the photon-tab tutorial (the videos) and it is very enlightening, exactly what a tutorial should be.
Here is a picture from my photon-tab, with the result. It looks much much better than before, but still it has some problems.
As you can see in the Final Gather image there are still some strange bright spots and there are no good contact shadows on the photo (under the gun), the gun and the cigarette pack.
How can I improve this?

Cheers,

Simon

[jure]

On FG tab change "PATH" setting to 1 or 2. Also you may want to try Lightmap instead of Photonmap?

[Janusz Biela]

1. I suggest use LIGHTMAP in PHOTONS TAB.
2. Still PATH PASSES option You have 0 .Should be 1 and 50%-100%.
3. With that small SPATIAL TOLERANCE You can use bigger BLUR SAMPLES (2 or 3)
4. Also parametr N in PHOTONS TAB should be bigger (3000-5000 is good level, enough to smoth nicely photons and make in Final gathering phase better and faster interpolation. I know, during photons shoting phase high parametr N make longer first step of position photons...but better is sacriface 1-2 min of time render to receive better GI (You will . For fast prev I suggest small N (for example 200-400) and PRERENDER in FINAL GATHER as 0 without passes...

[sarford]

Hi guys,

After more playing with some of the settings I got this result and I'm fairly happy with it.
Render time about 45 min at 1920 * 1080 on 8 cores.
Thank you both for helping me, without it I would never have gotten this far!

Cheers,

Simon

[Janusz Biela]

I think your time render should by much faster (around 10 min). Very high setup you have and still PATH 0.Spatial tolerance is too small. Better use 0.06-0.08 and min/max distance 50%/300%.