Chaos Corona Forum

Chaos Corona for 3ds Max => [Max] Feature Requests => [Max] Resolved Feature Requests => Topic started by: Tamyl on 2020-04-10, 19:01:45

Title: Sample multiplier per material/object?
Post by: Tamyl on 2020-04-10, 19:01:45
Hi there. While the sampling algorithms are already great and do the job perfectly in 99% cases, there some cases where one object is much more noisy than the other. Sometimes because of its material, sometimes we don't actually know why :) Instead of improving the sampling methods, is it possible to add a spinner value called "Sampling multiplier" in a CoronaMtl (or maybe in the object properties instead of material?) to upsample a specific object?

I'm adding an example of it - the image looks decent except of the black chair, which is pretty noisy.
Title: Re: Sample multiplier per material/object?
Post by: TomG on 2020-04-10, 19:35:27
This would be contrary to the philosophy of Corona :) In the case of the chair, does it have a bump map on it, and are you using Corona High Quality Denoising? (things with bump maps get denoised less so as not to lose the detail in the bump map). Also not entirely sure I would call that noise, can you share the material for that? It looks more like an accurate representation of the material (noise is usually a pattern of darker and lighter pixels while this looks like scratches on the material)
Title: Re: Sample multiplier per material/object?
Post by: Tamyl on 2020-04-17, 16:17:00
That's right, it has a bump map on it. If I remove it - the noise disappears, but I don't want to remove it. In the animation there are fireflies flickering randomly on this surface, so doesn't it mean the chair is undersampled comparing to the other objects in the scene?
Title: Re: Sample multiplier per material/object?
Post by: TomG on 2020-04-17, 16:21:16
Depends, if you are using denoising, it may just be getting denoised less (and so more rendering passes/lower noise limit would be a solution there). But, can't really tell without seeing what those fireflies look like, and without knowing if you are using Corona HQ Denoising.
Title: Re: Sample multiplier per material/object?
Post by: Ondra on 2022-01-14, 21:20:42
we wont add individual sampling multipliers, sorry ;)