grain in cloud

[Tangled-Universe]

You're cryptic  What doesn't help much, the settings I gave you? AA was 5, detail 0.5. Cloud Quality 0.4 as said in last post.

And your general advice; leave RTA alone  You mean no defer atmo? That's what giving me the grain!

I didn't mean to be cryptic, sorry
I missed the 0.4 cloud quality, sorry for that as well, but didn't know that AA was 5.

Of course RTA/defer atmo looks better, with enough samples and enough AA it will pretty much always look better, but is also (much) slower.
(I need to stop saying RTA, because it's now called "defer atmo", but they are the same thing)

I suppose you're considering using RTA for rendering your final wall project?
If so, what settings do you want to use there for rendering your terrain and objects/populations?
It's why I was suggesting to not do crops on atmosphere only, despite that you want to fix an issue specifically related to the atmosphere.
The reason for this is pretty simple, since rendering with defer atmo using AA>4 is slower than "normal" rendering.
AA4 is in pretty much all situations the point where deferred atmo rendering becomes slower than normal rendering.
So unless you want to render your project in AA4 I would turn off defer atmo and bump up cloud quality till the desired amount of grain.

I hope I have explained myself a bit better now

[Oshyan]

Ulco almost always uses (relatively) low AA Martin (I believe AA5 may be the *final* goal for the project), he's not doing AA 12-16 like you do. Therefore Defer is a legitimate option for him. Although his test above shows higher render time, it also shows lower grain. If the grain is equalized the render times may be equivalent or better for Defer. Meanwhile Defer gives *higher quality cloud edges* with main detail below 1 (which is how Ulco will render). Since he's already tested the rest of his scene at AA5, as long as he keeps AA the same while adjusting cloud and atmo samples to get the results he wants, then testing on this crop is fine (because it's changing AA that would affect render times on vegetation, etc.).

- Oshyan

[mhall]

Ulco, you'll want to keep in mind that, once printed and installed in the museum, that grain may not be visible in the least. As the final output for this is print, I think you would best be served by evaluating test prints at various rendering settings at the distances you expect this to be viewed (I know I said in an earlier thread I'd stick my nose against this thing ), but you're not rendering for that scenario.

[Dune]

Thanks for your words, guys. Martin; you're quite clear now, and Oshyan is hitting the nail on the head. Especially since these (14) files are so big (9975x6000px), using higher AA and detail will skyrocket the render times, and people will wait in line at the museum's entrance in vain, waiting for the wall to be put up 
And Michael is right as well, most people won't notice a little grain (or a straight branch of a too simple tree), but I'm picky.

And Ryan; no I'm not doing layers (yet). haven't experimented with it yet, and I need to put 14 big files together again, and try to keep it as simple as possible. I'm afraid having even more files will block my machine (or mind).

By the way; I'm reconsidering the sky, reduced coverage now, but I'd like some really big clouds, and blue sky in other areas, so I'm going to set that up anew. Keeping the sky layer that's giving the shadows I want, but only as secondary (thus for shadows only).

[Tangled-Universe]

Ulco almost always uses (relatively) low AA Martin (I believe AA5 may be the *final* goal for the project), he's not doing AA 12-16 like you do sometimes Therefore Defer is a legitimate option for him. Although his test above shows higher render time, it also shows lower grain. If the grain is equalized the render times may be equivalent or better for Defer. Meanwhile Defer gives *higher quality cloud edges* with main detail below 1 (which is how Ulco will render). Since he's already tested the rest of his scene at AA5, as long as he keeps AA the same while adjusting cloud and atmo samples to get the results he wants, then testing on this crop is fine (because it's changing AA that would affect render times on vegetation, etc.).

- Oshyan

Slight correction added
My favorite setting is still AA8 and AA10 to a lesser extent.

I know what you mean and the way you think about it Oshyan.
It's just that I have never seen it work in the end being both the best and the fastest.

[Dune]

I've been doing some tests this morning (with a different file), and am not happy. Can't get the grain out of rather fat (but not high) clouds near the horizon and under the sun, with detail 0.6 AA 6, cloud quality 0.4 AND defer atmo! A crop took 15 minutes, while no-defer with cloud quality 1 took 4 minutes, and had only slightly more grain.

With clouds higher in the sky I got reasonable results; see pic. But there's a color difference between no-defer and defer!

So I'm not ready yet. I'll put up the atmo file for the museum here, see what you guys think of it. And also to find out what is happening if you render with no defer! Something strange, like repeating the prepass. This is version in 3.0.12.1.

I may reduce the buoyancy of the cloud fractal, as that greatly fattens the cloud, and thus induces grain.

[Oshyan]

I'm not seeing particularly noisy results in the crop in your file, but I did have to turn off Motion Blur because it was really messing up the comparability of the output. I don't actually see much noise even in the crops you posted, certainly an acceptable amount for printing. Are you still having problems with this? You described what seemed like a fairly noticeable and serious issue that didn't respond well to rendering setting changes. Rendering with Defer Atmo in TG3 on the TGD you sent results in very low noise results (albeit with higher render time)...

- Oshyan

[AP]

I made some adjustments. Try this unless I missed something here.

[Matt]

Hi Ulco,

I don't think ray fuzziness is helping, and is probably adding noise around the edges of the cloud. I would leave this at 0.

[Dune]

Thanks guys. It's ok now. I realized I'm very picky, a little grain is no big deal. It's only certain darker cloud areas near the horizon under the sun. I upped the atmo samples to 24, undid the ray fuzzyness. But I needed defer atmo, with only higher cloud samples I couldn't get the grain out. Though I didn't go over 1.
Thanks ChrisC, but would 'optimal' cloud quality be better than 'none (highest detal)'? And what would be the benefit of a 2D shadow mask? I must say, I've never done much work on clouds, and I should!

[Oshyan]

I assume you're referring to the Acceleration Cache in clouds. Usually with still images using Optimal is fine. It's in animations where you can sometimes see issues. There are occasional situations where you'll gain some notable detail by turning the acceleration off, but it's not that common in my experience. I would categorically avoid Ray Fuzzyness at all times because it's a somewhat experimental and advanced feature. 2D shadow mask can reduce render times but at the expense of shadow detail, and it only works for Localized clouds anyway.

- Oshyan

[Dune]

I am. Thanks, Oshyan.