Volumen Causic

[Sebastian]

Here, u. can have the .blend file. Hope you can get the fault !

[CTZn]

Hmpf... it's really no help for me, I don't use blender

But obviously the ior is set to 0 for the prism... I think you tweaked a material wich is not applied to the geometry and used another instead

Try to destroy unused materials in your scene and see !

[sprocket]

Hello,
You need to set the prism to have a higher precedence than your media, for example media precedence =10, prism precedence =15, also you might want to turn down your cauchy coefficient to something like 0.013, as your value of 0.5 is very unrealistic and probably a bit extreme for the precise reflections you need
I think thats it, you probably need to adjust the position of the prism a bit but it looks as if it will be ok...!
Funnily enough i made a similar scene yesterday morning and had exactly the same problem , but mine is not quite as inventive as yours hehe! heres what yours looks like after i made the changes above, couldnt let it render for too long as ive got another render cooking atm (the prism below).
Good luck man!

[Sebastian]

Woooa !! ^^ THX !!

But wtf is the precedence parameter ??

[sprocket]

Basically, if two different objects with a specular/medium material occupy the same space, indigo considers the object with the higher precedence to be the one occupying the space.
eg a small sphere of liquid inside a large glass sphere requires the liquid to have a higher precedence or indigo will just assume that the whole volume is made of glass and ignore the liquid
erm yeah precedence control is in the specular mat in blendigo, its underneath the 'tranparent' button.
hope that helps!

[CTZn]

OMG! Precedence... I totally forget about that !

Nice job sprocket !

[suvakas]

Nice ! How do you model those light beams? Any tips?

[OnoSendai]

Woo dispersive participating media caustics!!!

[Kram1032]

but

IoR 0 isn't possible and I guess, it should be higher than 1....
shouldn't it?


percedence D'oh! xD

you find it in blendigo on the right top of the specular material shader

[CTZn]

but

IoR 0 isn't possible and I guess, it should be higher than 1....
shouldn't it?

Yes it should, my mistake

[Sebastian]

Quote: Woo dispersive participating media caustics!!!

That's high level rendering !!!

[Kram1032]

yeah!

[sprocket]

Woo dispersive participating media caustics!!!

Better than DOF?

@ suvakas: Basically just model the same way as for the normal prism that Ono posted waaaay back. You need prism with the correct ior and dispersion, and a light shining down a loooong hollow cuboid to try and simulate a sort of parallel light beam effect through a rectangular slit. Pop the whole scene inside a cube with a fairly low sss material to get visible light beams. In my scene I also put it all in a 'room' with very dark diffuse walls, dunno if it helped but it seemed to speed things up! Hope thats what you were after

Posted a longer render in the WIP forum so as not to hijack this thread!

@Sebastian: Really looking forward to seeing your final render now

[matt]

These are some pretty impressive caustics here. I thought I'd get in on the action too. I set up a nice mirror box and was going to let the light bounce around in there for awhile, but I can't seem to get the beam to bounce off the mirror walls. I've tried both a high ior specular and a high ior, high exponent phong, but neither have worked. I would appreciate any help with this.