Aye, I disagree with Pumeco only on the topic of Maya... And also only because I actually use the program, and it's apparent he hasn't had that opportunity yet. I'm not going to tell you to go shell out for Maya, although I did and couldn't be happier. If you want to go professional, Cinema 4D is not yet an option in the real world. Although it's getting there really fast! But alas, Cinema 4D is still a Ray-Tracer, as far as I know. Nothing short of Photon-mapping or the new Maxwell rendering engine will give you truly realistic light-through transparency. Even the ridiculously powerful realtime engine Unreal uses fakes for this kind of stuff. Mostly, this is because the "rays" in "ray-tracing" are not light rays at all, but data-rays. They convey particular, 24-bit color information about specific pixels, and do not behave like Photons in any way. So what you're looking at if you want real, accurate caustics is something that will use one of the high-end renderers, such as Renderman or mental ray. These programs are VERY complex and ultimately versatile and powerful, and can take years of study to learn. So if you're just looking for caustics alone, then learn to fake it, or try out something like Cinema 4D or even 3DStudio, or Ligthwave which has dropped in price again recently... OR, just learn to fake it! Oftentimes, the results cannot be distinguished in a simple, still-frame render. Especially if you spend some time with it! The main difference is that you won't be able to animate such things fludily in Bryce, and of course render times. Bryce will take eons to render such a scene, compared to just a few seconds or minutes in mental ray... And since you already have a scene set up in Bryce, why not learn to fake it in the meantime? You can always use the experience in other, unseen ways... It's not about what our programs can do, but what WE can do WITH them! (nobody ever thought that Bryce would even have keyframing, back in version 1!)