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Hi guys!
I have a problem with rendering animation of the two interfaces glass\liquid. At the bottom of the glass, in water there is some jitter, similar to the melting sugar. How to avoid it? In attachment a video comparison of how it looks in vray (no problem) and octane. Thank you for any answer.

That's not a bug but a limitation. To render fluids in glasses correctly, the fluid needs to slightly intersecting the glass. You can achieve that in your case by using a slightly smaller glass than the one you used for the simulation.

here the glass is less than the liquid. the liquid traverses the glass. but rendered not correctly.

mikinik wrote:here the glass is less than the liquid. the liquid traverses the glass. but rendered not correctly.

Could you please send me the scene so I can have a look? Thanks.

sent link in pm

abstrax wrote:

mikinik wrote:here the glass is less than the liquid. the liquid traverses the glass. but rendered not correctly.

Could you please send me the scene so I can have a look? Thanks.

octane from problems with similar liquids. She always looks like oil

abstrax wrote:

mikinik wrote:here the glass is less than the liquid. the liquid traverses the glass. but rendered not correctly.

Could you please send me the scene so I can have a look? Thanks.

abstrax, funny situation. to look through and check you still can not, because in the octane standalone mesh is not updated if rendered animation. in 3ds max change rayepsilon does not affect this issue. correctly render this animation in octane will not work.
1. you can render motion blur correctly for one frame, animation is not rendered in standalone octane.
2. you can render animation without motion blur in 3ds max.
3. in any case, will have the effect of melting sugar. (((((((

mikinik wrote:

abstrax wrote:

mikinik wrote:here the glass is less than the liquid. the liquid traverses the glass. but rendered not correctly.

Could you please send me the scene so I can have a look? Thanks.

abstrax, funny situation. to look through and check you still can not, because in the octane standalone mesh is not updated if rendered animation. in 3ds max change rayepsilon does not affect this issue. correctly render this animation in octane will not work.
1. you can render motion blur correctly for one frame, animation is not rendered in standalone octane.

Are you using version 2.22.2? I can render the scene you sent to me. In fact, I'm currently rendering out that scene with some changes.

2. you can render animation without motion blur in 3ds max.

As I said in the 2.21 release thread, if the Alembic file has vertex speeds, it renders it. As far as I know (and I don't know much about the 3ds max API), there is no way to fetch vertex speeds from a 3ds max mesh. Dmitry will have a look at it, when he's got some time available/

3. in any case, will have the effect of melting sugar. (((((((

I think the biggest problem in your scene was that the specular depth was way too low, resulting those dark edges. I set the specular depth to 64 and then it looks better. The reason why you get those dark edges is that the paths entering the liquid there, do many many bounces until they leave the material again.
I also tweaked the environment, glass and liquid materials, the tonemapping and will send you the scene later. Please keep in mind that I'm no artist, so that's all I can do for now.

abstrax wrote: Are you using version 2.22.2?

no, in 2.22.1. indeed in the latest version everything is rendered perfectly! ) didn't see it.

abstrax wrote: I think the biggest problem in your scene was that the specular depth was way too low, resulting those dark edges.

problem is not in edges of liquid, a small amount specular depth specifically set to increase render speed. I attached a video which better shows what I'm talking about.

abstrax wrote: I set the specular depth to 64 and then it looks better. The reason why you get those dark edges is that the paths entering the liquid there, do many many bounces until they leave the material again.
I also tweaked the environment, glass and liquid materials, the tonemapping and will send you the scene later. Please keep in mind that I'm no artist, so that's all I can do for now.

thank you very much for help!

mikinik wrote:

abstrax wrote: I think the biggest problem in your scene was that the specular depth was way too low, resulting those dark edges.

problem is not in edges of liquid, a small amount specular depth specifically set to increase render speed. I attached a video which better shows what I'm talking about.

Thanks for that. I eventually realized that you were talking about the streaks at the bottom of the glass...

The problem is that the particle mesh at the bottom is not smooth but wobbly. It's not very bad, but visible. I think (but I'm not 100% sure here), that in Vray this effect is less strong, because they keep track of the IOR of intersecting volumes, thus reducing reflections and refractions at the intersections of the different media. We will have a look at it, but I'm not sure when we can solve the problem, since it's a more fundamental issue.

If there is any way to make the particle mesh as smooth as the glass, you can work around the issue for now, but I'm not sure if that's possible. Another thing you can do to reduce the problem is making the intersection between the liquid and the glass as thin as possible (moving the glass down by -0.05, helped a bit).

This is the rendering of the liquid as chrome to make the "wobbliness" more visible: