Help with my night scene (SOLVED)

[GIOLETS]

Here I've attached my night scene.
I'm quite satisfied from the results, but since I'm newbie with Octane, I ask some suggestions in order to improve:
- better noise reduction
- better setup parameters

In particular:
in my scene I've a lot of area light (some of them are IES light), and to avoid to run risk I've setted all of them at around 100 samples.
So first question is: what does this parameter mean? If I have setted 2000 samples for my scene it means that the lights are sampled 100 *2000? I'm a little bit confused ...sorry if it's a silly question.

Also having a lot of samples I have some areas (marked in yellow) with a lot of grains and noise.
Here I've tried some of the forum's suggestions like:
- use coehrent value =1 and Path term= 1 but as results I've noticed a lot of areas with noise, overexposed zone...
- rendering at double resolution (7000*7000)
but with no success
I think could be related to the use of area light with little size and the use og IES lighting (but I need these kind of lights).

Another last question is: I've read to better setup the "ray epsilon" parameter, my scene is in 1:1 centimeters scale, and large around 100 * 100 meters, in which way you suggested to adjust this value?

[GIOLETS]

I know that this is a problem already seen and discussed here, but believe me I have read a tons of post and experimentig a lot (also if I'm a newbie) with no much success, and now I am asking a little help or ideas in order to resolve and finish my actual work.
I don't want that someone resolve the problem for me, but only suggestion to apply to my scene about parameters, or kind of light to use in order to reduce the noise.
Thanks.

Luca

[glimpse]

Hi, Luca.

raise samples for those light around the building to something liek 1000 (leaving the rest at 100). what that does is basicle sample those light 10X more than others.

if You could export the scene as .orbx (as I don't use OctaneRender for C4D) I could take a look at it later if before mentioned tip would not help You out to clean the noise =)

cheers
tom

[GIOLETS]

1.part2.rar

(114.44 MiB) Downloaded 364 times

1.part1.rar

(114.44 MiB) Downloaded 322 times

1.part3.rar

(30.5 MiB) Downloaded 262 times

Here the .orbx exported.

thanks a lot for any help.

[glimpse]

Here the .orbx exported.

thanks a lot for any help.

have You tried to put more samples for those .ies lights?

[GIOLETS]

mmm.. actually the sample value is 100.
I've noticed that as type of light I've setted "blackbody" : here the first my mistake?

[GIOLETS]

I've tried to raise the sample value of the IES to 2000 but still with a lot of noise and grain (rendering @ 3500 pixel, 3000 samples)

[ChrisVis]

Hi Giolets,

I had a look at your scene. Not that easy to figure out, what light causes which noise.
What I discovered so far: If you change the "outer radius" in the Octane Light Detail settings of your IES original light from 2.5cm to 25 cm, the IES lights produce a lot less noise. But this also creates bigger lightsources seen in the rendering, which you don`t want to. But that shows, that the IES light noise is depending on the size of the Emitter... the smaller the Emitter, the noisier it is.
Sample Rate doesn`t have that much influence here. Blackbody Emission for IES lights is ok to use.

Maybe the instancing of your IES light might cause the problem. Have you tried setting individual IES lights?

The noise in the window you marked might be caused by the "light bulb" (lampada floor) inside... raising the sample rate to 700 or 1000 is helping here. Also the material settings of the cloth shape of the "Tenda" seems to be part of the noise there, using alpha textures (furnishings.fabrics.lace.mask-grey.png) in the opacity and transmission channel is harder to render for octane if there is not much light emitted.

The noise in the other Area you marked seems to come from a light source insight the house. First I thought it is caused by the 3 candle lights, but turning them off didn`t help. So there might be a problem with your texture light sources insight. Some of them are blackbody emitters using textures in the distribution channel.... better use texture emitters for these ones.

Sorry, thats all I could find out.

Be sure to check out the lighting tutorial by inlifethrill...
http://render.otoy.com/forum/viewtopic.php?f=87&t=46052

Greetings,
ChrisVis

[ChrisVis]

Another thing to try out:

Turn the power of your HDR from 0.05 to 1 and the exposure of your camera down from 3 to like 0.2 - that gives octane a lot more light that is bouncing in the scene, so calculation is much faster.
You might need to adjust all your other light sources to get similar results, but overall this should be a lot faster with less noise.

Use Hot Pixel Removal with 0.8 - 0.9.

Also checkout the Render Settings and Optimization tutorials:
http://render.otoy.com/forum/viewtopic.php?f=87&t=45722

Greetings,
ChrisVis

[GIOLETS]

Thanks a lot ChrisVis!!!
Now I try all your suggestions reporting here the results.

thanks again.