Not work caustic render in Corona v.7.1

[pavel2405]

Guys, who know how to do caustics in corona render v7.1? I want do this
I have this
this's my sheder

[Ondra]

change render engine from progressive to bidir/VCM

[pavel2405]

not work bidir/VCM

[Ondra]

this should work, are you using displacement? Try playing with the displacement height (increasing it)

[romullus]

Does single plane have to produce caustics? I think it must have some thickness for that. Sorry if i'm wrong.

[pavel2405]

I ge t caustic effect by adding displacement. But it does not looks realistic. extruding the plane didn't make the effect better.

https://forum.corona-renderer.com/index.php?topic=923.0
i would like to repeat this effect in corona render?

[juang3d]

In fact you get pretty realistic caustics, the problem may be the render time needed to clean it up.

In your case I bet you have a diffuse light source like a big area light, this will give you what you show, blurred caustics, for sharp caustics you need a sharp source of light, like the sun or a point (or nearly point) light.

Check attached picture and scene.

Cheers!

[pavel2405]

In fact you get pretty realistic caustics, the problem may be the render time needed to clean it up.

In your case I bet you have a diffuse light source like a big area light, this will give you what you show, blurred caustics, for sharp caustics you need a sharp source of light, like the sun or a point (or nearly point) light.
Сould you gme scene in
Check attached picture and scene.

Cheers!

Its really works. Problem was in geometry and light (i had plane light)

Thanks guys for your quick reply. You have helped a lot. Rendering its magic!!!))

[naikku]

I want to say that I have never tried to do caustics in Corona, Juang3Ds rendering looks guite nice and that has been rendered fast :)
I did try before with Mental Ray and it took ages to finish an image. I too have to try caustics now :)

But in Pavels latest image, there is some fireflies on the water surface?

[juang3d]

In my max I'm not using the default Bidirectional engine, in the bidir section of the engine you have a rollout with several options, I tried it all and I picked the one the I found with less fireflies and good result.
Pavel is probably using the default one, it generates those fireflies in the water surface, I'm not sure if they will go with time (probably), but for this test I picked a different one (I don't remember the name right now)

Cheers.

[Ondra]

switch the mode to VCM to get rid of those fireflies.

[pavel2405]

switch the mode to VCM to get rid of those fireflies.

VCM mode works, but not very good(

[elnino]

Hi,
I made a similar test in Blender + Corona Standalone and noticed a strange behaviour.
When using VCM the render stopped after 178 passes. Nothing change on the render anymore even if rays stats continue increasing. The computer also stop processing.

[juang3d]

Have you tried the other engines to see if you get better results with them?

Cheers.

[maru]

I guess this is what is happens when you are using experimental features.