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colourful volume caustics!

Posted: Sun Apr 15, 2007 8:58 am
by sprocket
Well I made this test a few days back now, and recently let it cook for a bit longer...mmm pretty colours, not much more I can say really, I was quite pleased with the result and the subtle internal reflections and stuff :shock:
Ono you have made a very tasty renderer!!

Also thought I'd post the .blend file after some questions in another thread. If anyone uses it, please note that the way I have modelled the light source is definitely not the best way and is a leftover from a previous scene because I was in a hurry!
Haven't saved the .igi :evil: so no tonemapping (or continuing :( ), but it looks ok on my laptop, hard to tell with colour matching on an lcd...

O yeah forgot to mention, the prism mat is ior =1.72 and cauchy B =0.013, no absorbtion, uniform sss of 0.5. Also all rendered on a 2 core 1.6GHz Centrino Duo laptop... yum!

Posted: Sun Apr 15, 2007 9:20 am
by dougal2
very nice!

Posted: Sun Apr 15, 2007 9:30 am
by zsouthboy
Nice!

Posted: Sun Apr 15, 2007 11:25 pm
by dougal2
I had an idea to try and improve the ray beam - make it more parallel. I've no idea if this is even really possile in indigo, but anyway I've remodelled your light source with a small collimating lens.

Here's the results so far. I don't know what that bright streak is in the top right corner.

Posted: Mon Apr 16, 2007 1:54 am
by sprocket
Neat! But it looks kind of like you have 2 light sources or some odd caustics coming from the lens...!

Posted: Mon Apr 16, 2007 2:44 am
by Kram1032
that's from the lens but it looks great none the less ;)

Posted: Mon Apr 16, 2007 2:45 am
by OnoSendai
btw sprocket, would be nice to see a slightly angled down side view!

Posted: Mon Apr 16, 2007 3:32 am
by sprocket
Fair enough, the lens certainly ensures a beautiful rainbow effect!

I'll get some nicer renders as soon as possible, I'm currently rendering another test :D (tho I dont know if its even possible in real life) with more sss inside the prism to try and get an actual visible light beam through the prism. Looks like it will take forever to converge tho...

Posted: Tue May 08, 2007 11:27 am
by sprocket
Quick update! Did 2 more angles (slooowly, wish 0.8 had been out when I did this!) a week or so ago.
Back at uni now so my time is spent going between pub :D and revision :( with looming exams and less time to play with indigo, which is a shame with 0.8 out and everything... Anyways rambling over, bring on pretty pictures! For some reason the colours get really really saturated, but hey it's still a cool effect :P

Both about 3000 spp.

Back to lurking until my exams end I guess *sigh*...

Posted: Tue May 08, 2007 11:30 am
by dougal2
wow. that second one is a bit special.

Posted: Tue May 08, 2007 11:32 am
by sprocket
Quick reply! thx, yeah the colours get all chunky at the end of the beam tho...

Posted: Tue May 08, 2007 6:54 pm
by mrCarnivore
That render looks a bit strange. Did you use a wrong white point?

Violet (or purple) is not part of the spectrum of the light and therefore does not appear in a rainbow and should not be visible in your render...

Posted: Tue May 08, 2007 7:11 pm
by Anthony
Richard Of York Gave Battle In Vain
Red
Orange
Yellow
Green
Indigo
Violet

Violet is part of the visible spectrum of colours. The mnemonic knows all! And it does appear in a rainbow but it is really faint most of the time the red is the clearest and then it gets fainter from there. I would know because here in New Zealand it rains :wink:

Edit:Oops spelt mnemonic wrong :oops:

Posted: Tue May 08, 2007 7:25 pm
by mrCarnivore
Ok, I give up. A mnemonic HAS to be right! ;-)

I just looked the exact colours up. Seems like that shade of violet really IS part of the light spectrum. But other shades of violet (purple) are not!

Posted: Tue May 08, 2007 10:21 pm
by DaveC
Well, yes, mrCarnivore. It's known as Ultra-Violet. If violet were not part of the visible light spectrum, we would not know what colour violet was, would we. As we would not be able to see it. Violet wax crayons would be invisible. People in violet cars would cause many, many serious road accidents. And cyclists in violet clothing would not last very long (and would scare passers-by).

I really should stop drinking coke.