OTOY Forums

Hi everyone,
I'm working on a scene that contains a very high number of Octane area lights. They're inside several cloner objects (render instances off) and I'm getting some unusual results. With a few cloners turned on, it seems to render ok, however if they are all on, the scene actually gets darker.
Does anyone have any idea what might be happening here? Is there a limit to the total number of lights Octane can calculate?
I'd really appreciate any input anyone might have.
Using the currently most recent 2.11.1 RC-1 plugin and c4d r14.
Thanks

can you show me scene structure? I think you fall the mistake, collecting all emission objects to a single mesh

Hi Aoktar,
thanks for getting back to me. Attached are some images. It's a slightly complicated scene.
I'm going for this glowing-city look. The buildings are generated with simple geometry with a displacement material on them. The material is a specular material with absorption medium. Inside the buildings are the area lights. The buildings and the lights are in separate cloner objects, so I can use render instances on the geometry.
I want to have another instance of the buildings above, as if they are a ceiling. When I just have one row of buildings on the ground, it seems to work fine (see the second image attached) however if I duplicate it and put it above I get a very unexpected result (see first image)
I've tried everything I can think of! - Any idea what might be going on here?
Thank you!

Hi,
is your light sources arealights or meshes? This is critical question here. If you are using arealights, all will be exported as indivual meshes. Result should be as expected. But when you use meshes without under octane objecttag, all will be collected to a single mesh. this will be affect emission. There will be some normalisation over total surface area.

Hi,
I'm actually already using arealights. Initially I tried using emission materials on meshes, but I'm using an effector with time offset to stagger the animation of the light emission, so arealights worked best for that

MoGrafik wrote:Hi,
I'm actually already using arealights. Initially I tried using emission materials on meshes, but I'm using an effector with time offset to stagger the animation of the light emission, so arealights worked best for that

can you send to me only the illumination part of scene?

Hey, sure got it attached, thank you.
It's all there apart from the buildings. The rest of the scene is just cubes with Displacement / SSS Material covering the lights.
Please let me know if you can figure it out!
Thanks so much.

doing a quick reply but still checking. I think there is a crash on your scene. You have about 8000 lights. It may be so much for interactivity.

Just playing around, trying to troubleshoot the scene, it really seems like the lights on the floor has a drastic impact on the ceiling ones. I've attached some images demonstrating this. In order, the images show: 1: both lights on (the error. 2) top lights only. 3) bottom lights only.
Individually, the top and bottom light clones render fine. However when they are both turned on the top ones very much dimmer.
Please let me know if you have any idea what might be causing this! Really appreciate any help.

i'm testing current situation to understand what happens. But my opinion is that doing this with many arealights, very bad idea.
It slow down render and interactiviy. I have done similar and simple scene with materials over windows.