Let's share noise limits!

[Dippndots]

When you guys say 5%, are you talking about a setting of .05 in the Noise Level Limit under the pass limit? And then say .6 for Denoise Amount and 1.0 for Radius?

5 in the noise level limit (it's 0-100%), yes to the rest.

Something I would mention is if you I'm rendering below 1080p, I use a noise limit closer to 3%

[Frood]

When you guys say 5%, are you talking about a setting of .05 in the Noise Level Limit

Not 0.05 but "5". It´s % in UI

Good Luck

[steyin]

Got it, just read it on the help desk also. I suppose the larger the resolution the longer it takes even if the noise limit % is higher anyway of course. I tried setting the limit to 10 on a 5,000 pixel render and it was taking way too long (as I'm just doing tests), so I changed the resolution to 3,000 x 2,000. Still trying to figure out what settings to use for quick testing purposes and how this denoising works.

[Dippndots]

I like to region render the noisiest part of my image until it has enough passes that it looks clean enough, from there, I'd render the whole frame with that many passes and check what noise % that ends up being (noise % isn't accurate with region render). With noise reduction you can work back from that %  if the full frame took too long, or just use that % and put noise reduction on top of that for an even cleaner image.

[steyin]

Do you need to set a pass or time limit also? Or just set the Noise limit to 5/10/etc and let it go without the other limits set?

[Dippndots]

You don't have to, nor should you really, the render stops at the first limit it hits. It would never reach 5% noise if you had the pass limit at 1 or the time limit at 1sec, etc.

[3di]

what is the noise radius exactly?  I thought it might be pixels, but then noticed it went to decimals.

[Juraj]

I would love to know the relationship of radius to resolution as well. How low can it be used until some artifacts occur. (also why isn't it recalculable after the render is finished, would be useful feature to run denoising multiple times to see if lower radius would leave higher quality result).

Otherwise.. :

1) The denoising rocks. A lot ! I denoise previews between 2-5 perc. to absolutely final-quality mimicking result. (never going above 0.7-0.8 mixing with beauty pass). But even my previews are quite high-res, but I leave default 1.0 radius.
2) It could be little bit more sensitive to bump map effect, but that's pretty much it. No other artifacts, not splotches or anything (unless used at ridicoulously low rendering time, which doesn't make sense, c'mon, don't denoise after 2 minutes).

So, at what noise level do you guys call it a quit ? What is acceptable to you for commercial production (without denoising) ?

[steyin]

To be honest, I feel like using the denoising takes longer for my preview/test renders than just setting it to say 10 min. time limit. I'm probably still doing things wrong, but if I set the limit to say 10% with a .6 amount / 1.0 radius (without setting any other limits) the render goes for like 30+ minutes until it stops on its own. Sure it looks cleaner in the end, but that's 3x slower than just using the time limit without denoising.

Gonna hope for a tutorial on this to figure out why I'm not having success as I continue to play around.

[romullus]

So what limit you're setting, 10 min time or 10% noise? If former, then i find hard to believe that denoising phase takes two times longer than rendering itself, unless you're rendering giant resolution preview for 2 passes...

also why isn't it recalculable after the render is finished, would be useful feature to run denoising multiple times to see if lower radius would leave higher quality result.

I think i read somewhere, that that may come in 1.5. Fingers crossed.

[Juraj]

To be honest, I feel like using the denoising takes longer for my preview/test renders than just setting it to say 10 min. time limit. I'm probably still doing things wrong, but if I set the limit to say 10% with a .6 amount / 1.0 radius (without setting any other limits) the render goes for like 30+ minutes until it stops on its own. Sure it looks cleaner in the end, but that's 3x slower than just using the time limit without denoising.

Romullus answered this...but I am surprised you don't see this by yourself, why don't you set time limit in both cases ? Time, noise, or pass limit are 3 completely different thresholds. Denoising alone also doesn't require any of these thresholds, those are simply to stop rendering.

[Juraj]

BTW, for those of you who don't use 2017 yet, and want to use denoising together with VFB+ without setting any limit, it works like this:

1)Select CoronaFramebuffer (but keep it linear, and all your corrections in Native/VFB+), hit render. When you're satisfied, click "stop" which is required for running denoising (cancel does not, for future differentment in 2017 Max). Select your desired noise to beauty ratio.
2) Then simply click show framebuffer in 3ds Max which will always automatically show native (do NOT click the send to Max buffer in Corona buffer, that just starts some bastardized version of native without any controls at all). Voila, the image is copied perfectly.

Sadly, this link isn't maintained after initial copying, it seems to be one-trick pony. Yes, Corona buffer can send it there anytime, but that is the bastardized useless version of native buffer. I don't get what there happens.

[sevecek]

what is the noise radius exactly?  I thought it might be pixels, but then noticed it went to decimals.

The denoising radius has no straightforward interpretation, it's just a number that affects the strength of blurring.
For smaller values, the denoiser will keep more details in the picture at a cost of also keeping residual low-frequency noise ("splotches"),
higher values lead to more aggresive blurring.

[steyin]

So what limit you're setting, 10 min time or 10% noise? If former, then i find hard to believe that denoising phase takes two times longer than rendering itself, unless you're rendering giant resolution preview for 2 passes...

For one project I'm working on I have been setting preview images to 10 minutes, 3000px. I tried rendering the same image with a 10% noise limit (no other limits) and it took about 30mins to finish. Image was cleaner, but the 10 minute render was just fine, and of course took 1/3 the time. I realize the image size of course might be an issue, so I'm still playing with settings with a smaller resolution.

Romullus answered this...but I am surprised you don't see this by yourself, why don't you set time limit in both cases ? Time, noise, or pass limit are 3 completely different thresholds. Denoising alone also doesn't require any of these thresholds, those are simply to stop rendering.

Tried this also, but if the point of denoising is to get a cleaner image in less time then my time limit would need to go below 10 minutes. While the denoising pass takes about a minute or so depending, I'm finding that a smaller time limit with denosing is producing an image that is noisier than just rendering for the 10 minutes without denoising (in the case of the 3000px).


For final renders of this particular project (which I have been setting to 1-2 hour limit for a 5000px image) denosing will definitely help cut down that time, just seems it's not useful for previews/tests unless I go with a much smaller resolution.

[romullus]

I have no idea, why your experience is like that, but many people seems to reach exactly opposite conclusion - denoising is best to get fast & clean preview renderings :]