Some help wanted with caustics

[Erik de Graaf]

Hi all,

I am trying to use caustics for the firt time and i cant get it how i would like it.

Maybe someone can help me out.

This is a render done by flipside some time ago, i want the same caustic effect as is on the backwall.



This is what i am getting.



These are my settings.









I hope this is enough info.

Erik

[Erik de Graaf]

Ehm,

Maybe i asked a dumb question but i would really like to know what i am doing wrong. Maye someone can point me in the right direction for a good tutorial on this.

I have read the tutorial on caustics on this forum but i still can't get right.

Please anyone ?

Erik

[losbellos]

hmm, there are winows or not? If yes remove them. otherwise If something doesnt work help it to work, what I mean: photon map can be saved so you can make a kinda metal durface from your water, calculate caustics then save map, and then set back water material and render. (if you are satisfied with the caustics on the wall)
this is one way, I try to do something like this.

[losbellos]

eh remove the reflection map from the reflection slot.. at least until you make caustics. leave off frensel, then you calculate the caustics, and then you make anything you want with your water. I tried it here it works

[Erik de Graaf]

I got it .



I used a spotlight instead of a direct light and used it only to cast caustics and now it looks great.

thanks for your reply losbellos.

Erik

[marina]

Nice effect.
Could you post your settings, please? (for spotlight, I mean)

[Erik de Graaf]

I used all the default settings, except for the subdivisions i set them to 1400.

I don't know why but according to the tutorials i set my let to inverse square falloff resulting in a multiplier of 90 million. i use millimeters in my scene, maybe that is the cause of it.

the caustic settings are,

- multiplier 0,5
- search dist. 75
- max photons 6

i hope this helps you.

Erik

[marina]

90 million!!
Maybe I have to increase my multiplier a little

Thanks, Erik

[losbellos]

thats why better use direct light.
I think change the angle a bit that more coming in, might look better.

[Erik de Graaf]

So it does work with a direct light ?

I couldn't get it to look like this with a direct light no matter what setting i changed.

I would like to know why with a spotlight it works for me and with a direct light it doesn't.

Erik

[losbellos]

good question, but I Never use spotlight for caustics beacuse of the multipliers. If you post your scene I could look into it. I have also made one yesterday it works fine with it.

[Erik de Graaf]

Here it is.

(removed)

Please don't look at the website, it is our company's and it is sooooooo out of date that i am ashamed of the images there.

I am working on an update of the site.

Erik

[losbellos]

hmm,I dont know. I rebuilded the scene and worked the same.
Interesting later I'll look at it again.

But the above picture's problem look like caustics setup (parameters) problem.