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Chaos Corona for 3ds Max => [Max] General Discussion => Topic started by: Dippndots on 2016-05-17, 13:03:44

Title: Let's share noise limits!
Post by: Dippndots on 2016-05-17, 13:03:44
What % are you guys finding works enough for your projects before using the denoiser?

I'll add pictures soon, but it looks like we can get away with rendering to ~5% noise and using .6 on the denoise for our 720p animations.
Title: Re: Let's share noise limits!
Post by: Frood on 2016-05-17, 13:06:16
You just shared my personal defaults :)

Good Luck

Title: Re: Let's share noise limits!
Post by: cecofuli on 2016-05-17, 14:05:38
5% is the limit if you have not strong DOF or MBlur. Otherwise, you need  < 2%, I think.

Anyway, for indoor architectural animation, a value between 2%-5% is good enough =)
Denoise? 0.75 is the limit, in my animation test.
For still, better 0.5/ 0-6
Title: Re: Let's share noise limits!
Post by: Dippndots on 2016-05-17, 14:19:02
yeah, I agree cecofuli, I think we might aim for 4% since we can afford to, the render times are about 30% of 1.3 with 5% noise, so a bit more time is definitely ok.
Here's the resulting 5% noise test
Title: Re: Let's share noise limits!
Post by: romullus on 2016-05-17, 14:21:52
When you're sharing those denoise numbers, are you talking about denoise radius or denoise blending?
Title: Re: Let's share noise limits!
Post by: Dippndots on 2016-05-17, 14:28:12
just blending, haven't played with the radius yet
Title: Re: Let's share noise limits!
Post by: cecofuli on 2016-05-17, 14:35:08
Denoise amount. =)
Title: Re: Let's share noise limits!
Post by: romullus on 2016-05-17, 14:47:25
I must admit i'm rarely touch denoise radius too, although it helps to find better balance between  noisy and too plastic looking image. Let's hope that someday we'll get denoising that is fully adjustable after rendering. If i'm not mistaken, it was said that it could be delivered in 1.5 already.
Title: Re: Let's share noise limits!
Post by: Ludvik Koutny on 2016-05-17, 14:48:14
I use following:

8-10% for quick previews combined with denoising
5% for finals that I plan to denoise
3% for finals that I don't plan to denoise
Title: Re: Let's share noise limits!
Post by: johan belmans on 2016-05-18, 09:07:29
@ Rawalanche

do you use the same values for interiors and exteriors?
Title: Re: Let's share noise limits!
Post by: blank... on 2016-05-18, 10:10:25
I didn't have the chance to test it extensively for interiors but for exteriors, I had to turn it off. Had a fine bump map on the building that needed to be "noisy", and denoiser made a mess on the grass.
Anyone else had similar exterior experience?
Title: Re: Let's share noise limits!
Post by: Christa Noel on 2016-05-18, 11:15:34
I love denoiser so much (thanx corona!!),
I always use 4% with denoise blend 0.6
Denoise radius is 0.6 too, because I experienced that with 1.0 it hurts my tiny leather bump texture a little bit. but I don't know is it still happening in 1.4 or not.
Title: Re: Let's share noise limits!
Post by: Juraj on 2016-05-18, 11:35:46
What is the relationship between radius and resolution ? Would use guys still use smaller than 1 radius for high-res renders ? Would there be any possible drawback (splotching?) ?
Title: Re: Let's share noise limits!
Post by: Christa Noel on 2016-05-18, 12:02:14
What is the relationship between radius and resolution ? Would use guys still use smaller than 1 radius for high-res renders ? Would there be any possible drawback (splotching?) ?
I have no idea about that, but imho it is related. I think I wont use smaller than 1 for denoiser radius for more than 4k renders. but I never get any project with more than 4k render.
Title: Re: Let's share noise limits!
Post by: steyin on 2016-05-20, 18:30:20
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?
Title: Re: Let's share noise limits!
Post by: Dippndots on 2016-05-20, 18:57:54
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%
Title: Re: Let's share noise limits!
Post by: Frood on 2016-05-20, 19:05:37
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
Title: Re: Let's share noise limits!
Post by: steyin on 2016-05-20, 19:27:51
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.
Title: Re: Let's share noise limits!
Post by: Dippndots on 2016-05-20, 19:36:00
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.
Title: Re: Let's share noise limits!
Post by: steyin on 2016-05-20, 19:48:07
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?
Title: Re: Let's share noise limits!
Post by: Dippndots on 2016-05-20, 20:21:31
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.
Title: Re: Let's share noise limits!
Post by: 3di on 2016-05-21, 05:29:03
what is the noise radius exactly?  I thought it might be pixels, but then noticed it went to decimals.
Title: Re: Let's share noise limits!
Post by: Juraj on 2016-05-21, 23:41:09
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) ?

Title: Re: Let's share noise limits!
Post by: steyin on 2016-05-22, 08:21:39
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.
Title: Re: Let's share noise limits!
Post by: romullus on 2016-05-22, 09:26:40
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.
Title: Re: Let's share noise limits!
Post by: Juraj on 2016-05-22, 10:09:24
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.
Title: Re: Let's share noise limits!
Post by: Juraj on 2016-05-22, 10:26:50
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.
Title: Re: Let's share noise limits!
Post by: sevecek on 2016-05-22, 16:40:09
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.
Title: Re: Let's share noise limits!
Post by: steyin on 2016-05-22, 18:30:31
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.
Title: Re: Let's share noise limits!
Post by: romullus on 2016-05-22, 19:11:47
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 :]
Title: Re: Let's share noise limits!
Post by: Dippndots on 2016-05-22, 19:40:36
Steyin, if you set your render time to 9min and turn on denoising, what does that look like compared to 10min? Surely it looks better.
Title: Re: Let's share noise limits!
Post by: Juraj on 2016-05-22, 20:51:02
Steyin, if you set your render time to 9min and turn on denoising, what does that look like compared to 10min? Surely it looks better.

Of course it's this.

Your 10 minute render has much higher noise ratio (more than 10percent) than the latter with 30 minutes (but 10perc. noise ratio is still very high, very noisy). But there is no relationship between that time and threshold.
If you had written down the noise ratio that you had after 10 minute first render, than used the exact noise ratio as limit for the next one, it would be done again in 10 minutes. And they would look identical.

Using any kind of limit, has no effect on actual performance.

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).

This is almost impossible, because the overhead for additional passes needed for denoising is rather small. It can produce 'ugly' result (because high noise would produce artifacts and loss of details), but not 'noiser' (noiser=higher noise ratio).

Steyin, aren't you completely just confusing the hell out of it ? Denoising, has nothing to do with Noise threshold limit.  And 10 minute render against 10 minute render with 1 minute denoise will look dramatically better in favour of denoised, with exception of quality loss if noise ratio was too high. But if it was too high to begin with, than your non-denoised test would be ugly and noisy as well.

My 7680px (8k) renders take 8 hours on 40 cores. With denoising, I can denoise after 2 hours (where I have reached about 2.5 +/- noise ratio) and get literally almost the same result, minus some bump map loss.
The same goes for my 2560px tests, I just don't have any numbers from head right now.

Can you post screenshots with framebuffer Stats page open ? Maybe you encountered a bug that needs solving but surely looks like something more trivial.

Title: Re: Let's share noise limits!
Post by: steyin on 2016-05-23, 00:50:04
Steyin, if you set your render time to 9min and turn on denoising, what does that look like compared to 10min? Surely it looks better.

Of course it's this.

Your 10 minute render has much higher noise ratio (more than 10percent) than the latter with 30 minutes (but 10perc. noise ratio is still very high, very noisy). But there is no relationship between that time and threshold.
If you had written down the noise ratio that you had after 10 minute first render, than used the exact noise ratio as limit for the next one, it would be done again in 10 minutes. And they would look identical.

Using any kind of limit, has no effect on actual performance.

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).

This is almost impossible, because the overhead for additional passes needed for denoising is rather small. It can produce 'ugly' result (because high noise would produce artifacts and loss of details), but not 'noiser' (noiser=higher noise ratio).

Steyin, aren't you completely just confusing the hell out of it ? Denoising, has nothing to do with Noise threshold limit.  And 10 minute render against 10 minute render with 1 minute denoise will look dramatically better in favour of denoised, with exception of quality loss if noise ratio was too high. But if it was too high to begin with, than your non-denoised test would be ugly and noisy as well.

My 7680px (8k) renders take 8 hours on 40 cores. With denoising, I can denoise after 2 hours (where I have reached about 2.5 +/- noise ratio) and get literally almost the same result, minus some bump map loss.
The same goes for my 2560px tests, I just don't have any numbers from head right now.

Can you post screenshots with framebuffer Stats page open ? Maybe you encountered a bug that needs solving but surely looks like something more trivial.

I'm sure I'm overthinking it, just gotta get used to what is the right way to go. I tried the same settings (10% limit, .6 amount) for a 4000px render on another job (which I would render for 4 hours without denosing) and the image with denoising finished in about 30 minutes, almost looking identical to the non denoised one, so obviously I'm doing something wrong on the other job. Will have to fiddle some more as the one I'm having issues with is at work, so it'll have to wait until tomorrow.

**EDIT**

After some more tinkering, I have got my previews down to 5-7 minutes. I lowered my resolution to 2400px, and realized I had my GI sampling balance still set higher for final renders (d'oh), so I lowered it back to 16. Left noise limit at 10% and amount at .6, ended up with a preview that had 14.1% noise and took 5 mins 24 secs, which looked good enough for test prints. I went back and increased GI to 24 samples and the render took 7 mins 15 secs, so all is good now.
Title: Re: Let's share noise limits!
Post by: fabio81 on 2019-07-03, 12:43:55
My 7680px (8k) renders take 8 hours on 40 cores

Hi Juraj,
I know it's been a long time and that there have been new big improvements with the latest versions of Corona, but can I ask you what noise threshold useful for rendering 8k?
I'm doing rendering from 5k and I'm setting 6% noise limit, does it seem acceptable or could I get even 7% or decrease?
Thank you
Title: Re: Let's share noise limits!
Post by: Juraj on 2019-07-03, 14:33:22
I find the noise threshold to be very unrealiable as it doesn't account for texture detail well imho.

If I have an office scene that's 40perc. of image covered in that classic noisy office carpet, the image could be absolutely crystal clean and the Noise would still say 4perc.
But if I have clean white space with food flooring, even 3perc. could look still noisy to me, in bad way.

And worst, if I have scene with large white negative space, like white-sweep studio product scene setup in shadowcatcher material, the Noise Threshold would say 0.8 (!!) noise ratio despite the scene only getting 25 passes and AA still looking terrible.
So I don't use noise threshold at all.

Recently, the new noise filter ("HQ Filter") makes noise looks much more pleasing to my eye so higher threshold is now lot more acceptable.

But I don't have any fixed numbers, I go by how it looks to me. I make some crops and see what they look and then set finals for per-passes limit (i.e 200 passes at 16 GI/AA).
Title: Re: Let's share noise limits!
Post by: fabio81 on 2019-07-03, 14:41:45
thank you for your answer Juraj,

but 200 passes for an 8k are not many?
this is the image where I am working (5000px x 3300px) and I set 6% noise. I'm rendering in a dual 2697V2 but soon I'll do it in a Ryzen 2990wx 32core. I think 6% goes just fine
Title: Re: Let's share noise limits!
Post by: Juraj on 2019-07-03, 14:48:01
I said that just as random example. I always strive to have perfect AA and for that I need 100 passes...of anything. Whether it is 100 passes as 16 GI/AA or 8,..32.. depends on particular scene. My interiors never have AA issues so I use 16 or 32 GI/AA, for my studio scenes I use 8...or even 4 when I do a lot of Optix denoising so I have the fastest feedback.

But sometimes I need like 500 passes at even 16 GI/AA if the scene is really really problematic with both AA noise (DOF) and and complex GI & Direct light.

Some interiors I do take 1 hour even for 8k rendering, and some 20 hours. The more bounced the light is around complex materials the worse it is...I really go by eye.
Title: Re: Let's share noise limits!
Post by: fabio81 on 2019-07-03, 14:49:42
thank you very much for the explanation :D
Title: Re: Let's share noise limits!
Post by: cgbeast on 2019-08-28, 20:55:12
Noise level limit set to 5 = 5 percent.
Title: Re: Let's share noise limits!
Post by: cgbeast on 2019-08-30, 03:47:22
Wow...20 hours.  That's a long time these days.  I'm used to rendering 4k images between 30-40 min with denoiser. Max 1.5  hours. So far with 5 percent I've been getting 1:45 on a single machine.
Title: Re: Let's share noise limits!
Post by: serch on 2019-08-30, 18:40:17
Wow...20 hours.  That's a long time these days.  I'm used to rendering 4k images between 30-40 min with denoiser. Max 1.5  hours. So far with 5 percent I've been getting 1:45 on a single machine.

What are your workstation specs?
Title: Re: Let's share noise limits!
Post by: cgbeast on 2019-09-04, 19:08:55
Dual Xeon 3.00ghz
128 gb of ram
GTX 1080 gpu