gi caustics and other questions

[vance3d]

2 questions:

1.

Does anyone know how refractive GI caustics are generated?

I mean do they follow the settings in the caustics dialogue or are they pretty much set automatically with no means of adjusting them?


2.

How come when I have an object that is 100 percent white sitting on a 100 percent reflective black surface the reflection rendered is not white but a midtone gray? The only way I can get the reflection to be white is to turn the dark level multiplier up under color mapping.

thanks,

Vance Miller

[flipside]

1. They are GI related, they are caustics generated by the second and third and so on - bounces of light. So they are adjusted by the settings of your GI (irradiance map or whatever)

2. I did a small test. A black 100% reflective plane and a grey non reflective plain with a white box on top of it. The reflection of the white box is not tinted at all, it looks exactly the same as the box itsself.

Are you not using fresnell reflections or something? Do you use vray materials (my mats are vray)

[vance3d]

Thanks for the reply.

I don't know what was going on with that reflection cause I just tried it again and it worked fine!!!!

as far as the gi caustics go you really didn't answer the question. With normal caustics you can make them stronger or more defined with settings in the caustics section. Is this not possible with gi caustics? I know you can increase caustic multipliers on objects but what about other things like the search distance or max photons?

Vance Miller

[vance3d]

OK

Note to self. Always apply 100 percent reflective material to surface BEFORE rendering and jumping to conclusions.



Vance Miller

[flipside]

What I meant was that they are related to your GI settings, there are no other controls like for normal caustics. Even the caustics multipliers in the material don't have any effect on the GI caustics.

[Aleksander]

tutorials on VRAY

I am not sure if this helps but who knows?: ) Have You seen www.evermotion.org? You can see quite nice movies-tutorials on working with VRAY.