Determine Samples/Pixels for clean render (?)

[rappet]

Hi Guys,

I am trying to determine a general 'rule' to set the needed Samples/Pixels to render a pretty clean (or clean enough) render (?)
It woulde be nice what to find out and compare our findings

My field is exterior DL archviz, but we can go for all kind of renders ofcourse.

To start you could agree or disagree on me:
When the render pass Ambient Occlusion with AO (default) hit the max samples 1024..
.. that is the moment to accept the Beaty Render Pass as being good enough.
Out of experience I found this moment to estimate the needed Samples/Pixels,
and makes it quiet easier for saving time.. because when not paying attention the AO, I usually am rendering more then neede (to be sure)

Quit curious for your two cents?

greetz,

[nuno1980]

Hello.

Do you want few or many hours of render, sorry? -> If for sun on earth,
you want to make caustics at scene of any specular material at PMC kernel with default except no caustic blur, 5k- or 10k-reject and parallelism 1 then 150k or 200k spp (samples/pixel) at resolution screen of 1002x602 or ~50k spp at 2560x1600.
If you want animation then PT or PMC kernel with default caustic blur as 0.01.

Therefore, congrats for your many high-end videocards.


VERY IMPORTANT: all specular materials have always dispersion in real life. If you ask what dispersion coefficient number and what refractive índex then you contact me here (but unfortunately my PM is locked :S )

[rappet]

Hello.
Hi Nuno1980

Do you want few or many hours of render, sorry? -> If for sun on earth,
you want to make caustics at scene of glasses/water/stones... at PMC kernel with default except no caustic blur, 5k- or 10k-reject and parallelism 1 then 150k or 200k spp (samples/pixel) at resolution screen of 1002x602 or ~50k spp at 2560x1600.
If you want animation then PT or PMC kernel with default caustic blur as 0.01.

Maybe I am not that good in telling the story... I am not looking for settings needed in the specific Render Kernels,
but regardless gpu's, kernel used, materials used and so on... I am trying to figure out if I ('we') can estimate how to set the max Samples/Pixels to get a good DL (or other) render. Doing different kind of projects over the past time I have noticed that when looking at the AO Render Pass hit the 1024 spp, the DL render pass is clean most of the time.
(btw: I am using the ArchiCAD plugin and I can switch from the AO to Beauty pass without losing the rendered samples).
So most of the times I stop rendering before hitting the max spp by checking the reached AO spp.
So I was wondering if you guys do this the same or have other ideas about estimating the needed max spp to get nice renders?
Hopefully I made my purpose more clear?

Therefore, congrats for your many high-end videocards.

Yes, thanks! I am very proud and more then happy with those beasts

[nuno1980]

Hello.
Hi Nuno1980

Maybe I am not that good in telling the story... I am not looking for settings needed in the specific Render Kernels,
but regardless gpu's, kernel used, materials used and so on... I am trying to figure out if I ('we') can estimate how to set the max Samples/Pixels to get a good DL (or other) render. Doing different kind of projects over the past time I have noticed that when looking at the AO Render Pass hit the 1024 spp, the DL render pass is clean most of the time.
(btw: I am using the ArchiCAD plugin and I can switch from the AO to Beauty pass without losing the rendered samples).
So most of the times I stop rendering before hitting the max spp by checking the reached AO spp.
So I was wondering if you guys do this the same or have other ideas about estimating the needed max spp to get nice renders?
Hopefully I made my purpose more clear?

Set-Max samples.JPG

Set-AO Max samples.JPG

Why do you use DL kernel? Has the animation 30 or 60 fps?

I use ALWAYS PMC kernel without "caustic blur" despite single GTX 780 Ti Classy but not for animation. ...But I'm rendering "weddings' glass" scene at 1st time for resolution of 3840x2400.
I don't like DL nor PT because DL has much less photorealism than other kernels. And PT makes very hardly complex caustics at sun on earth.

[grimm]

I don't think that you are going to find a general rule of thumb for the number of samples. It really depends on the scene and it's textures and lighting. What i do is to render several frames from the animation where there might be issues. Dark areas, object closeups, etc. Render each one until they look good and then use the highest for the entire animation. If there is a huge difference between them you might want to look at splitting the animation up into smaller pieces so you can speed the process up.