yafray and volumetric lights

Hello, there!
I’m new on this forum, and I don’t have enough time to model with my favorite (our favorite) software.
I’ve a small… ok, I’ve a huge problem with an underwater environnement render with yafray : I can’t use an underwater lightprobe (I cannot find one…) and I really need to render that scene with that effect : my model is a fish. I approach the goal, but it still misses the effect I want : caustics refraction illuminating my fish underwater.
I give you my last pic to comment…
Thanx if anyone know the marvelous solution!
![file:/C:/Documents and Settings/thomas/Mes documents/perso/Fichiers_Blender/Didi/Images/didi_02.jpg](file:/C:/Documents and Settings/thomas/Mes documents/perso/Fichiers_Blender/Didi/Images/didi_02.jpg)http://C:%5CDocuments%20and%20Settings%5Cthomas%5CMes%20documents%5Cperso%5CFichiers_Blender%5CDidi%5CImages%5Cdidi_02.jpg
http://blenderartists.org/forum/C:%5CDocuments%20and%20Settings%5Cthomas%5CMes%20documents%5Cperso%5CFichiers_Blender%5CDidi%5CImages%5Cdidi_02.jpg Tom
http://blenderartists.org/forum/C:%5CDocuments%20and%20Settings%5Cthomas%5CMes%20documents%5Cperso%5CFichiers_Blender%5CDidi%5CImages%5Cdidi_02.jpg

caustics refraction illuminating my fish underwater

Make a photonlamp to light through a tranparent surface with IOR = 1.35

This tranparent surface must reproduce water surface conditions such as color and waves.

thanx a lot!
I forgot this!
I cannot post a pic, but I’ll learn to!
Tom

About posting pics, I suggest www.imageshack.us

When your image is uploaded, copy paste in the elysiun missage box the Hotlinks for forums (1) code

http://img408.imageshack.us/img408/6382/didi040lu.jpg

Now, you can see what I try to do! Top one pic is without effects, the second one is with the effect.
BUT, it’s done in “GIMP”.
I wanted to do this with YAFRAY.
I’ll succeed, I know, but when? lol
http://img502.imageshack.us/img502/9636/didi054rl.jpg