想請教caustic 的問題

[deshk]

I follow a tutorial, and try to recreate a wine bottle and a glass of wine.
I turn on both "emit photons" from the key light, and "caustic" and "raytracing" from mental ray render. But somehow it doesn't look like it has created any caustic. Btw, the rendering time with caustic turned on is just same as the rendering time without caustic.
I did double check the setting from the tutorial, I don't know what went wrong.

Can anyone explain roughly how it works please? And what I need to pay attention, when I try to use caustic? thanks

[stantang]

Are you using raytrace shadow for your lights?

[deshk]

yes I'm using raytracing.

- Use Ray Trace Shadows is on
- Light Radius: 0
- Shadow Rays: 1
- Ray Depth Limit: 1

[stantang]

yes I'm using raytracing.

- Use Ray Trace Shadows is on
- Light Radius: 0
- Shadow Rays: 1
- Ray Depth Limit: 1

You probably want to raise the Ray Depth Limit as the shadow can't pass through your glass and wine with just 1 for that setting.

[deshk]

I have just run a test, I increase the Ray Depth Limit to 10.
It makes no changes on the render.
And I check the final scene of the tutorial, it's interesting that the Ray Depth Limit is 1 only.

I think Caustic doesn't like me : p

[stantang]

I have just run a test, I increase the Ray Depth Limit to 10.
It makes no changes on the render.
And I check the final scene of the tutorial, it's interesting that the Ray Depth Limit is 1 only.

I think Caustic doesn't like me : p

May be you want to increase the Max Photon Depth as well.

[deshk]

thanks, I will try : )