OTOY Forums

I'm currently working on a scene where the only main lightsource is a very bright filament lamp.
The filament is very small but should emit a lot of light (like in the real world).
For the filament i made of course a small mesh that functions as a blackbody emitter. So far so good.
The problem is now, that i can't get this small mesh bright enough in octane.
The maximum power of 100 at the octane blackbody option is far to low.
Is there something i have overseen? Is there a possibility to get it brighter?
In the scene i'm working on, i can't fake anything or at least it would be very sad if i would have to.
The clue of the scene should be, that everything is physically correct.
So for the scene i need a point-like light source and i liked the idea, to build it like in the real world with a filament as a blackbody emitter.

1. Question:
Has someone an idea? Or am i maybe just to stupid and this is not a problem at all? Did i oversee something?

2. Question:
I also tried to get a satisfying result by tweaking the camera options (iso and gamma) to brighten the picture, but i got to much noise at 64k samples/px. Is it possible to increase the maximum of 64k samples/px?

thanks in advance
andi

Hi Andi,

From what I understand, from other similar posts,

For more information see: http://www.refractivesoftware.com/forum ... f=9&t=4176

The problem (simplified),
Tracing rays from the camera's view to that tiny, thin emmitter like a fillament usually miss the actual light source, expecially those that have already bounced off a surface or two.

The Current Fix (That I know of)
Create a "shell" around your bulb, such as copy and scale the glass a few mm out from the surface. Then in Octane use that shell for the actual light emitter and set its opacity to completely transparent, making it invisible.

The Future Fix - The new Octane Rendering Kernel thats been talked about with its bi-directional ray tracing. YAY!

Thanks for the answer Qtoken!

I was thinking about if Octane is bidirectional. I thought it should be cause it's so fast. But on the other hand it explains the difficulty’s I have with small light sources.
But anyway, it should be possible to solve this problem with more samples/pixel. Sadly 64000 samples/pixel is the highest value one can choose
Or is there a possibility to render with more samples? Does anyone know?
Will bidirectional path-tracing be in the next version?

Andi