Caustic Sampler

here is a caustic sampler (angolair style!):

and for those who can’t see how these caustics evolve:

raytransp / raymir / raytrans raymir

and here is a bigger raymir:

hope you like it!

Do you use a cornell box for your caustics?
If not how do you do them?

Those caustics are just fantastic, some of the best i’ve seen here. What are the exact settings for them.

Hey nicely done caustics Prince.this incurages me to make an animation test with caustics.I have a few glass Ideas.

Hopefully I smell a tutorial incoming. :wink: Those are amazing!

are the caustics rendered with yafray?


Hey, Prince I had accouple of questions I was hoping you could help me out with.I never used cuastics before But I figured out the basics with trial and error.I first started with the Photonlamp at a low photon count alittle more then 10000 blur about 270 depth 3 blur 333 and used QMC.This gave the render noisy cuastic dots.So I turned things up abit the photon count up to 200000 ect.And it gave better results but the cuastics were still noisy.I was woundering if you could tell me what the settings you used for the Yafray GI and the Photon lamp settings.This way I wont have to go through trial and error and wait for each reander to finish.This would help me tremindously.Thank you.

“I found a bug,a new improvement with yafray is that you can press escape and when the next data block is finished it will exit the render.But when you are using photons the render doesn’t exit untill the render is complete.and that sux when going through trial and error”

cekuhnen:are the caustics rendered with yafray?

Yes caustics are rendered with yafray.Blender has the new photon lamp, enabled when you choose yafray for the renderer.

First off i am glad that you all like them! i am flattered that you would think them better than angolairs and that on top of that you overlooked the modeling errors! Thankyou alot!

Now to the dirty facts…

the caustics are rendered with yafray

no cornel box (i have never fully figured area lamps out!) - i use a sort of simple setup of a plane, the model, two sun lamps with no shadows and a single spot with a photonlamp

the exact settings are alittle general and i don’t recall them exactly but they are something like this:


600000 photons
156 search
12 raydepth
.016 blur


raytransp = 1.5
raymir = .04
alpha = 0

other values are non essential but the traceshadow should be on and the others can be experimented with

if you want some seriously cool images with glass (with or without caustics) use traceshadows on both the glass material and on the plane beneath. The alpha values must be greater than about .025 to have any shadow at all though! Experimentation is essential though!

so do you want a tutorial?

Good GOD yes! I’m new to Blender and don’t really know what you just said, but a tutorial is the best way to learn what’s being said. :smiley: So, yes PLEASE. :wink:

lol! you got it! if only for you I think it will be well appreciated (i hope - it better be! :x :smiley: ) although i would still like to know if others want one too! i’ll work on one in my spare time - tell me what you want to see in it: lot’s of images or what?

:wink: Prince :wink:

Images are always helpful, but no necessary, necessarily. As long as I know what you’re talking about & where to find it, I’ll be fine. People with more experience should probably voice-in here and give their $0.02 about it, though.

My point: I’d love a tutorial on that a LOT! :smiley:

Well heres what I got from a cornell box.
Im gonna try it the way prince did it. (not same scene though)

Whats a cornell box? Pardon the noobishness, but I think alot of us are wondering the same thing.


Here we go I found a tut.
Have fun.

Well I did the best I could without a cornell box.
Didnt get the caustics but I got a really good looking suzanne.

Nicely done, prince, but there are some rather large issues. First, all of the images are quite washed out, and the caustics are rather hard to see. Second, the text is really pixelated, and detracts from the overall image. Third, are you using good AA settings on the Suzanne render? Keep it up. Use a higher photon count if you want better settings, and don’t let your renders get so washed out, it ruins the detail of the caustics.

As the results of the vote already shows: A TUTORIAL PLEASE :smiley:

:o Thats a very nice work Prince, and if you could do a tut it will be really nice too.

tell me what you want to see in it: lot’s of images or what?

I guess what would be most helpful to me is, along with a tutorial, to have a systematic series of simple images that demonstrate the ranges of the various settings and their effects on the scene. Sometimes this is done when new features are released on blender3d, but not they’re not always very in-depth or clear. To have a reference site that gives visual demonstration of all of blender’s (and yafray’s) many settings and features would be an awesome timesaver. Most of this info is out there, but its very distributed and unorganized. A forum on this site might be a good way for users to create their own for the benefit of the rest of us!

fret not! fret not! a tutorial is coming - i will be submitting it to the administrators to put it as a sticky for futur reference and it is going to be a series of experiments and a good (well in my opinion) explanation of the caustic setup as well as numerous images of settings and 3d views. It won’t be done for atleast a few days but in the mean time you can experiment on your own!

hey gryphon - what do you think you are doing putting images in my thread!? just kidding - i don’t mind really but you should have perhaps asked first or atleast submit only thumbnail links! but never mind that - critics on your image… it is very good object wise (lots of nice meshes) but the shadows are terrible and the artifacts are worse and the lighting messes with the eyes - hey if you want it that way it’s great but it looks bad to me - not that mine is any better mind you! :wink:

angolair - the image is suppose to be washed out and i used low (200000 phtotons) count on the monkey ones so it is reasonable that the caustics look blotchy. Yes the text was an after thought and i can’t help it unless i use some other method (which i may in futur cases do!) thanks though!

i’ll keep you posted on the tutorial! :wink:

thanks all! :wink: