Caustics...How to?

[mario]

I have a little problem: with a thin lens model, ( material glass with IOR 1.2) i can't view caustics....Why???
I have see a beautiful cardioid caustic in Artwork gallery, but i dont have nor a little caustic....
What's the best parameters fo a lens glass?
Suggestions?
Thanks
Mario
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Ho un piccolo problema: per quanto provi, non riesco ad ottenere caustiche, con un modello di lende in vetro (IOR 1.2) non vengono fuori... Perchè?
Qualche suggerimento?
Grazie
Mario

[Kram1032]

1) Please show an example
2) Please post a part of the scene
3) Which V of Indigo do you use
4) ... Ok, I think, that's it..

Maybe, no light is falling on / trough the lens, or all the other light is too bright, to see any caustics...

[mario]

Oh, the problem is with 0.6, 0.7t5, 0.7t1!!!
I can't post the image because i'm not able to post it, but in the scene there is only a little lens , a plane and a sun light...
Material is transparent, with IOR of 1.2. Suggestion for material?
Excuse me, but i'll try to post the image..
Thanks

[Kram1032]

use either http://www.imageshack.us
or
http://photobucket.com
most are using first one, I'm using second one

[CTZn]

Most are wrong

[Kram1032]

I thk so, too!
That's why I'm using photobucket

[mario]

OK, the image is here
http://img375.imageshack.us/my.php?imag ... 199ln2.png
and this is with 0.6, bidirectional on
In Blendigo, when i try to export the file, whwn bidirectional is on, he say " Fatal error : bidirectional disabled"!!!
Why?
Thanks

[Kram1032]

Very simple:
Blendigo is written for 0.7.x, where BidDir is disabled, 'cause of a bug.
Indigo would crash with BiDir on...
Don't use Blendigo for 0.6.x, where BiDir works: It wont work propperly with any transparent mat!
Here, in this pic, I can see caustics

[mario]

OK, this is with 0.6 and BiDir on!!
So, in 0.7 is impossible to obtain caustics???? Is correct this trouble?
In 0.6 or 0.5 or another without BiDir i can't see caustics!!!

javascript:emoticon(':roll:')
Rolling Eyes
Suggestions???
Thanks!!!
Mario

[CTZn]

I'm not sure but I think there are caustics in your scene, since every light passed through a medium or glass is a caustic light. Maybe we would need to see a closer and different point of view. But the caustics of your sphere are strange, looks like every face is separated from its neighbouring, must be a geometry issue.

[Kram1032]

I'm not sure but I think there are caustics in your scene, since every light passed through a medium or glass is a caustic light. Maybe we would need to see a closer and different point of view. But the caustics of your sphere are strange, looks like every face is separated from its neighbouring, must be a geometry issue.

Here, in this pic, I can see caustics

Caustics

Maybe, you don't know, what caustics are... Check out the link

It's light, that either is bundled through a transparent material or by a mirrormaterial.
This description may not be completely correct, but it should be near to the phnomena

Indigo 0.7 IS able to produce caustics, but for some reason, there is a Bug with BiDir... So, atm, it's deactivated...
An other thing is, that Blendigo exports 0.7-Mats, which are completely entirely different to 0.6-Mats. That's, why you shouldn't use it for 0.6!

[mario]

Ok, in the image i can see two caustics: one from the sfere, other from the lens.
In 0.6 all is Ok, but in 0.7 I don't understand if is possible to obtain caustics, without BiDir: exist a method? Is the wrong setup of the material? Have you a setup for 0.7's caustics?
The second question: I love 0.6, but with Blendigo i can obtain easily bump mup and others, but 0.6 works very well for others works!!!
Suggestions?
Thanks
Mario

[Kram1032]

Caustics are possible in 0.7 just like in 0.6!
BiDir (I think) just makes them appear faster but slows down the general render-speedity...
But I want to have it back anyway!!!

[mario]

Thanks, i'll try and, when my work is OK i'll post it.
Thanks
Mario

[Kram1032]

np