Awesome, thanks!
Any chance you could attempt to do some equal time renders?
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Here we go (I forgot to adjust the size of render time stamp):
Light Tree OFF - No Clamp - 500 Samples
Light Tree ON - No Clamp - 420 Samples
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Thatâs noticeable, for sure. Thanks for running those tests!
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Thatâs a significant reduction in noise - great work.
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Itâs because the devs donât think artists are smart enough to use a 0-1 slider. If they ever do add it they will entirely break itâs current functionality by making it automatic which makes it basically useless.
Itâs an artistic tool as well as an optimization. In production you should never really use 0 but if you are rendering cartoons or npr things 0 is almost entirely acceptable and will be so insanely fast and noise free in just a few samples
It can cut render times in half or more on GPU and reduce noise significantly. Itâs obvious they donât understand how important this feature is itâs honestly getting ridiculous how stupid they think the blender community is.
Sergey can add the most complex simplify ao option which Andrew price canât even comprehend but Lukas canât add a 0-1 slider to cut render times in half.
I suggest we all tell them to get over them selves and add it to masterâŚ
if you donât get good results with it on guess what⌠You can turn it off. Itâs our choice to use it. Itâs not like itâs forced on us wtf
We use it every day in production. There hasnât been a single render since itâs implementation in to our build that we havenât used it
Also donât forget to ask about dithered sobol 
all functional features we arenât allowed to have in master for some silly reason. Doesnât work as good as Arnoldâs ? Cool but it works and it makes our renders cleaner. Itâs something else we have used on every single render since itâs implementation
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Sureeee. Man in The High Castle, Silicon Valley, The Mindey Project and many more production shots were rendered with scrambling around 0.1
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Do you have any evidence to back that up?
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Because I was the render TD for all those projects. I also made that video we are taking about. Which was entirely doable because simplify ao but scrambling is not at all useless in full gi scenes
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So does that mean that scrambling is only usable with simplify AO, or will scrambling help also in scenes without added fake AO (simplify)?
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Scrambling works in every scenario not limited to simplify ao. The reason simplify ao was on is because I wanted to give a quick but totally reasonable final render in just a few samples
We used this in a few of our actual production shots on a music video that hasnât been released yet getting sub 3 second frames
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This sounds pretty production proven to me 
Come on, guys! Put it in master, maybe as an experimental option.
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Oh yes, dithered sobol!
Did show obvious pattern with denoising on. But never mind that, was well usable without it. I too used those experimental versions in production. Without, i would have never finish quite a few projects in time. All this would be fine included under experimental option, since most of newbies donât even bother to take a glance at the Blender manual⌠FFS!
What are dev. affraid of?
Dumb will do dumb things! Itâs part of life - learning, evolving process. Thatâs why we 're here to help each other. Not to prevent experiments or worse, prohibit falling, but to persevere by showing mercy, offering help to stand up again and climbing to the top then flying or jumping down⌠landing softly or breaking bones itâs an amazing part of the experience.
I think iâm plain stupid-dumb because i donât learn how to set env., troubleshoot & build own custom version.
But on the other hand, honestly, iâm tired of all this⌠been contemplating for a long time nowâŚ
i realized itâs better and cheaper for me to do my work best as i can and buy/subscribe to what i need to when i need it. And in the meantime live life, share my attention with loved ones that also care for me and my opinion. Respect.
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should we ask them politely to put scrambling distance under experimental option on dev talk ?
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I think we should force them to put it in Blender.
Iâve used it myself and it made everything so much better.
It was especially cool in the viewport with the reduced noise, because you could get a feeling for what the scene would look like much faster.
And in the final renders the image would be much cleaner.
Who needs Lysol if you have scrambling distance?
I see no reason why they shouldnât add it to master 
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one more voice for including it in blender.
granted, it doesnt work for all scenes but i had one scene where the use of the scrambling distance feature cut the render time down to 10% whitout any visible artefacts (crystal/glass reflection/refraction stuff). real timesaver!
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Yes, scrambling distance would be very great to have.
Maybe a bit hidden somewhere or inside an optimization panel, where all the options that save rendertimes but can affect the render quality can be found. I donât really see the point of not having it, maybe @brecht can explain why ? I donât think itâs a matter of preventing people to have bad renders when not used correctly.
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Can someone compile the scrambling distance Branch?
For Windows?
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What is scrambling distance?
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https://developer.blender.org/P366
(the patch is outdated, it does not work with the current master)
Hereâs an up-to-date version of the patch: https://github.com/lukasstockner/blender/tree/scramblingdistance
But guys, please, calm down a bit. Me and the other Cycles devs arenât complete idiots, if this patch was all happiness, sunshine and faster renderspeeds if would have been committed 2 years ago.
If you listen to anybody who really knows what theyâre doing in terms of renderer development (for example at Siggraph just a week ago), you always hear the exact same thing: What a practical renderer needs is consistency and predictable and reliable results. This is why everybody moves to path tracing - you donât need to tweak 100 different settings to make it work like you would need with stuff like irradiance caching, you just render until the noise is gone and thatâs it.
And exactly there lies the problem with this patch - it completely breaks this fundamental property of path tracing. Every Cycles user is used to just rendering until the noise is gone because the underlying math guarantees that youâll have the correct result then, but with scrambling distance < 1 that is no longer the case. Yes, the image will be noisefree - but you can also get that from Blender Internal or Eevee. The entire point of Cycles is to be a physically based renderer that gives you the right result.
The scrambling patch tricks you into thinking you have a clean image, but you donât know for sure anymore - with a small scrambling distance, it is entirely possible that an entire room suddenly is 30% brighter because you moved a single lamp by one centimeter. Yes, seriously. Now imaging youâre rendering an animation with an animated lamp. This brings us back to the advantages of path tracing - you donât get flickering, individual crappy frames in the middle of your animation or any of that stuff - if the render settings work for a few frames in the shot, theyâll work for all of it. Unless you reduce scrambling distance.
I hope this makes it a bit clearer why this patch is so problematic - itâs not just a neat trick like many other features, it completely sacrifices the design goals and fundamental advantages of a path tracer.
Also, just to make sure - yes, if you know what youâre doing, you can get good results with it (see e.g. everything Theory does). However, if youâre an artist hoping to use this feature, youâre not the one who has to handle the bug reports. Oh, and there will be bug reports - we had people reporting âbugsâ because they mixed up left and right before and every few weeks thereâs a bug that just says âit doesnt workâ as the title and has the unmodified default template as the text. For another example, grab a few Cycles materials from Blendswap and check how many of them have two shader nodes plugged into a MixRGB node. The reality is that the people discussing experimental patches here are among the users with the most technical skills and many Cycles users just have no idea what it actually does under the hood. And thatâs fine because, once again, you want to have a path tracing renderer so that they donât have to.
And as a final note - please donât turn this into another Lukas vs. the other devs thing, we had this a few years ago for D808 and even back then it was bullshit. Just to be completely clear, I 100% agree with the decision to not have this feature in official versions, not even as an experimental option.
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