Settings for animation

[busseynova]

Just going through the process for setting up my next animation and I'd like to get the settings nailed this time. Last one had some issues at the rendering stage which I hope can be avoided without the need for loads more passes.

Attached are two crops of the raw footage. two quite different issues, but they may be caused by the same thing? I am wondering if they can be fixed by AA vs GI setting. On the scene with the glasses, this was set to 16, the glass material is pretty standard with refraction, but no caustics and with a bump map for the pattern.

The brick scene was GIvsAA of 32 (I didn't set the scene up)

I'm wondering whether blur/sharpen could have caused/exacerbated these effects? Would I be better off applying blur and sharpening in AfterEffects, which is maybe better suited to interpolating across the frames of a moving image?

Thanks in advance! Would really like for this project to be less of a bodge than the last, and part of that will be nailing the settings down early on.

[busseynova]

Embedded videos:

[agentdark45]

Following for future reference. I too have trouble with using DOF in animations.

[maru]

Hi, I am sure there is a way to render both flicker-free, but first we will need to understand more about the scene itself:

Glasses:
1) Are you using path tracing only, or path tracing + uhd cache? (performance tab) I would suggest using path tracing only in this case.
2) Are you using denoising here? I would suggest switching it off, as it can produce different results for different frames, especially with not enough passes.
3) How many passes per frame is this?
4) What kind of lighting are you using? Corona's Sun+Sky? HDRI? The idea is to understand what is this bright highlight in the glass material.

Wall:
This is definitely displacement being re-calculated for each frame. For animations with moving cameras, the solution is to:
1) Use bump maps for fine details, and displacement only to define the overall structure of the material (e.g. bricks)
2) Switch from screen-space to world-space displacement in the performance tab (this will prevent flickering, but displacement will be calculated for the whole object, even if its outside of the camera frustum, so more RAM may be required.
3) Adjust the displacement size in the performance tab to find good balance between quality and RAM usage (lower values mean higher quality displacement, but more RAM usage)

In case of the glasses, you can try the following advice:
https://forum.corona-renderer.com/index.php?topic=19065.msg119271#msg119271
https://forum.corona-renderer.com/index.php?topic=14429.msg101324#msg101324
https://forum.corona-renderer.com/index.php/topic,16522.msg104046.html#msg104046
https://forum.corona-renderer.com/index.php?topic=19628.msg122645#msg122645

[busseynova]

Hi, I am sure there is a way to render both flicker-free, but first we will need to understand more about the scene itself:

Glasses:
1) Are you using path tracing only, or path tracing + uhd cache? (performance tab) I would suggest using path tracing only in this case.
2) Are you using denoising here? I would suggest switching it off, as it can produce different results for different frames, especially with not enough passes.
3) How many passes per frame is this?
4) What kind of lighting are you using? Corona's Sun+Sky? HDRI? The idea is to understand what is this bright highlight in the glass material.

Wall:
This is definitely displacement being re-calculated for each frame. For animations with moving cameras, the solution is to:
1) Use bump maps for fine details, and displacement only to define the overall structure of the material (e.g. bricks)
2) Switch from screen-space to world-space displacement in the performance tab (this will prevent flickering, but displacement will be calculated for the whole object, even if its outside of the camera frustum, so more RAM may be required.
3) Adjust the displacement size in the performance tab to find good balance between quality and RAM usage (lower values mean higher quality displacement, but more RAM usage)

In case of the glasses, you can try the following advice:
https://forum.corona-renderer.com/index.php?topic=19065.msg119271#msg119271
https://forum.corona-renderer.com/index.php?topic=14429.msg101324#msg101324
https://forum.corona-renderer.com/index.php/topic,16522.msg104046.html#msg104046
https://forum.corona-renderer.com/index.php?topic=19628.msg122645#msg122645

Glasses:
1) yep PT&PT
2)yep denoising
3) I'm not sure, I set the noise limit at about 6% from memory
4) I think that was Corona Sun& Sky but the person who set that file up had a weird mix of HDRI/Sky in a few of them, I did strip that out on most of them, I think this one too.

Wall:

Ok thanks, I'm moving away from using displacement on animations where possible because of render times but that's all good to know.

Cheers! I'll check those threads out tomorrow.

[maru]

3) I'm not sure, I set the noise limit at about 6% from memory

Unfortunately this doesn't tell us much, as the same noise limit may produce different results in different scenes. I would say that for things that need a lot of AA like details in refraction, you probably need about 100 passes (or more). You can lower GIvsAA to get more passes rendered in the same time, at the cost of GI quality.

4) I think that was Corona Sun& Sky but the person who set that file up had a weird mix of HDRI/Sky in a few of them, I did strip that out on most of them, I think this one too.

This is very risky as it can lead to persistent fireflies (maybe that's exactly what you are getting in your renders):
https://corona-renderer.com/bugs/view.php?id=1257
https://corona-renderer.com/bugs/view.php?id=2124

Please try to simplify enviro lighting as much as possible - use sun+sky only or HDRI only, without overrides, unless they are absolutely necessary.

Ok thanks, I'm moving away from using displacement on animations where possible because of render times but that's all good to know.
Cheers! I'll check those threads out tomorrow.

If displacement fits into your RAM, it should not affect render times that much (apart from pre-render displacement calculations, which should be pretty fast). I would try to experiment with world-scale displacement to see if it produces good calculation time/quality results, and get rid of it only if there are any problems.

[busseynova]

Cool, thanks for the help. And agreed, it's a stupid lighting setup that caused me no end of hassle, not helped by someone moving the HDRI files on our server!

If displacement fits into your RAM

What do you mean by this? Is it related to the pixel size of the map? like 1024 x 1024 px?

[maru]

If displacement fits into your RAM

What do you mean by this? Is it related to the pixel size of the map? like 1024 x 1024 px?

You have displacement quality controls in the Render Setup > Performance tab under "Displacement".
-If you are using "screen size" mode, your displacement will be calculated only based on your current camera position, so that everything that is outside of your camera view is flat. Also, it will be calculated "intelligently" so that the further areas are less detailed, so in case of animations you will end up with flickering. The lower the "screen size (px)" value, the smaller details are allowed, and the more memory is required.
-If you are using "world size" mode, your displacement will be calculated for the whole object(s), even if they are outside of the camera view. There is also no "adaptivity" in the displacement, so the mesh will be tessellated evenly. This however results in flicker-free animations. The lower the "wold size (units)" value, the smaller details are allowed, and the more memory is required.

The size of the displacement bitmap (e.g. 1024x1024 px or 8k x 8k) should not really matter that much - RAM usage will be similar.

But the render output resolution will matter - e.g. if you render with displacement screen size set to 2px in full hd resolution and in 8k resolution, because in both cases the geometry will be tessellated with smallest detail of 2px allowed.