How can I reduce noise in renders? [solved]

#1

How can I reduce the noise on diffuse surfaces in the Reflectance Channel when using the Physical Renderer but also maintain a reasonable render time ?

[EDIT]

So apparently my thought about increasing samples under the light object attributes or mess around the options under the GI tab was wrong.

All I had to do was increase the Max Blurriness/Shadow/AO/SSS Subdivision Samples under the Physical render tab.

I always use the Irradiance Cache as primary and Radiosity Maps as secondary method of GI because they produce the fastest possible result.

At last I have my balanced render settings.

If you want you can post your own Α vs B renders and time to support your own settings so others can also benefit.

#2

Hi Demis!

3d Fluff has a really good video about this…

Willem

#3

What kind of material system are you using? I mentioned in a previous thread that I find using a reflective layer on top of a diffuse layer in the Reflectance channel to be noisy.

It’s probably bad practice, but I prefer using a Colour channel and the reflective layer set to Additive. It’s actually slightly slower to render but way less noisy. I also find the overall colour/brightness to be more in line with what I expected from the bitmap images.

For rendering I now almost always use Physical set to Progressive, with GI (QMC + QMC). This is quite a brute force method, but it’s quick for previewing and when it comes to final render you just set how many passes you need. You just need to throw plenty of CPU cycles at it.

I find for big, busy scenes, between 6 and 10 passes does the job. Of course with R21 you can also add a denoise at the end, which might save a few passes or just provide a cleaner image.

This is not, by any means, a recommended or silver bullet system – Its just the way I work after much experimentation. I also tend to use HDRIs or the Physical Sky with sprawling, outdoor scenes. Your mileage will undoubtedly vary!

EDIT: And if anyone has a better, quicker method, I’d love to hear it. Rendering is never fast enough.

#4

Thank you everyone!

#5

If you have R21, use the denoiser.

#6

Unfortunately I don’t because I don’t have Win10. And even if I did I don’t have a compliant denoise GPU. (NVIDIA GeForce GT 720M)

#7

The denoiser is intel’s and works on all CPUs. :slight_smile:

Does R21 require win10? Because I love the denoiser, and I think you’d find it very handy. But I don’t know what other apps you may have that rely on Win 7.

#8

Yes it does require win10.

I’ve tried the denoiser from an other application (I don’t remember which was it, could be a renderer) and had a messages error telling me that their AI denoiser does not support my hardware. Ever since when I read Denoiser in renderers I assume it’a an AI denoiser. I thought C4D’s r21 denoiser was also an AI one.

#9

This one is CPU based, so you are good if you upgrade to win 10/R21. :wink: