Saving light cache for animation problems - Vray Next

[brunonz]

Hello everyone,

We are rendering an animation at the studio and we would like to save the light cache to save some time. I have searched a couple of topics suggesting that you don´t need to enable use camera path (for camera movement) or don´t use the save from file option at all with BF+LC. Vlaro and others suggests that it won´t cause any flicker when we calculate LC for each frame on animation.
The render itself is perfect, we don´t have any issues, but we need to save the LC to save some time at the render farm. But the issue we are facing is that the frame is taking 1 hour instead of 15 min when we save the Light cache with "use camera path" option.

Is that a know issue? How should we proceed?

Thank you

[tashko.zashev]

Hi,

This is too big difference in render time. Do you have to V-Ray log for those renderings ? Can you send us a scene file which we can use for internal tests here ? Best to have both setups, the slow one and the other one where you render without precalculated LC.
Do you save just one LC file for the entire animation - Use camera path On ?
Issues like this are difficult to troubleshot without repro scene file.

Update
Can you test a few frames with Use camera path Off with presaved LC ?

[brunonz]

Hi,

This is too big difference in render time. Do you have to V-Ray log for those renderings ? Can you send us a scene file which we can use for internal tests here ? Best to have both setups, the slow one and the other one where you render without precalculated LC.
Do you save just one LC file for the entire animation - Use camera path On ?
Issues like this are difficult to troubleshot without repro scene file.

Update
Can you test a few frames with Use camera path Off with presaved LC ?

Hello,

Here is the link for both scenes (Single Frame LC and Pre computed LC) https://we.tl/t-GA231d6F1l

Could you give us some light????

Here is the workflow for our animation render:

- Render a single frame with "use camera path" ticked and "don´t render final image"
- After that, we save the LC file, untick both "use camera path" and don´t render final image" and render the whole sequence.

Am i missing something here? This is not prioritary to this scene, it happened before with another project and Vray Next.

We appreciate it.

[brunonz]

Hi,

This is too big difference in render time. Do you have to V-Ray log for those renderings ? Can you send us a scene file which we can use for internal tests here ? Best to have both setups, the slow one and the other one where you render without precalculated LC.
Do you save just one LC file for the entire animation - Use camera path On ?
Issues like this are difficult to troubleshot without repro scene file.

Update
Can you test a few frames with Use camera path Off with presaved LC ?

Hello,

Just an update. I think the problem is related to the adaptive dome option. Maybe is not working properly when saving the light cache file to an animation.

[brunonz]

Hi,

This is too big difference in render time. Do you have to V-Ray log for those renderings ? Can you send us a scene file which we can use for internal tests here ? Best to have both setups, the slow one and the other one where you render without precalculated LC.
Do you save just one LC file for the entire animation - Use camera path On ?
Issues like this are difficult to troubleshot without repro scene file.

Update
Can you test a few frames with Use camera path Off with presaved LC ?

Hello,

Is there a solution for my problem? Could we provide any other information?

Regards

[tashko.zashev]

Excuse me for the delayed reply Brunonz,

Just completed the tests renders with your files and the render slow down for the provided workflow is reproducible. We are actually don't have support for the adaptive dome light in Light cache from file mode yet, and this workflow seems to add a lot of fireflies to the rendered image. That leads to excessive render time, because the sampler is trying to reach the noise threshold using the max subdivisions set.
The case is marked with high importance and as soon as we have any news will post here.

You can use the Single frame mode until we manage to add the necessary improvements to the builds.

[brunonz]

Excuse me for the delayed reply Brunonz,

Just completed the tests renders with your files and the render slow down for the provided workflow is reproducible. We are actually don't have support for the adaptive dome light in Light cache from file mode yet, and this workflow seems to add a lot of fireflies to the rendered image. That leads to excessive render time, because the sampler is trying to reach the noise threshold using the max subdivisions set.
The case is marked with high importance and as soon as we have any news will post here.

You can use the Single frame mode until we manage to add the necessary improvements to the builds.

Hello Tashko,

Thank you for the reply, it is clear now what happened.

Regards