Caustic etc

[enzyme]

Just one simple question: Caustic and GI. Does Octane actually capable of doing them? I have seen some cool renders here that actually have caustics. When I search for such topic, I could not find any.

On my computer, I actually never see any Caustic result inside Octane. Maybe I did not set the Specular or Glossy material correclty?

Also, recent update has GI option and this PMC thing that I have no idea what for. Maybe anyone here can give examples and explanation.

Can we see more documentation, tutorials of Octane in near future? These days, I am using Octane via Blender and really interested with they both development, especially since Blender is getting Cycles soon officially.

Thanks.

[matej]

Caustics work with pathtracing & PMC kernels (which are both 'GI'), not with directlighting. PMC gives better results (less fireflies) when caustics are involved.
If you need specific help, show renders / post a test scene and people will help.

especially since Blender is getting Cycles soon officially.

Do you have any links to this claims? Last time I checked Cycles (2, 3 weeks ago, it looked still very alpha to me)

[enzyme]

I use Octane so far for casual renders, mostly using "Daylight" setting for the light. That setting never seemed to give any Caustic effects. Does sun light really cannot give caustic? Is there a way around this.

Just now, I tried another setup using object to act as light emitter, interestingly enough caustic light effect appears when using Pathtracing. But the problem of using an object as light emitter is the shadow it is casting over the scene. Is it possible for something to act as light, but not casting shadow?

It's basic, but maybe it is not addressed completely in documentation.

I attached a really simple setup. Maybe Radiance has a good caustic setup example?

Thanks again.

[enzyme]

Regarding Cycles, I think when Blender hits 2.6, then Cycles is officially production ready. If you download latest build from GraphicAll, that Alpha version is quite stable. Crash less than before anyway. And if it is for basic render, Blender Cycles is quite capable already.

I like Octane a lot, but needs more plugin support, especially for Maya and Blender, they both should have up to date plugin.

[enzyme]

Another try.

I wonder if I put a light inside glass object, it would cast beautiful caustics....

[enzyme]

If I put light inside a specular object, it is indeed also casting caustic. But I wonder how to control the caustic result to be more focus or more blur.

[matej]

Sunrays doesn't pass through glass, so you won't get refracted caustics with daylight illumination, but you will get reflected caustics. Try a HDRI env. for caustics.

Is it possible for something to act as light, but not casting shadow?

No.

[matej]

But I wonder how to control the caustic result to be more focus or more blur.

By controlling the roughness of glass?

[enzyme]

Previously I use the film on specular material, but this one I just use multiple materials on mesh faces.

I wonder if there is a trick to get proper directional sun light that result in caustic.

[enzyme]

cheers matej, I will try HDRI. I will also check portal.