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dmack
10-03-2012, 11:08 AM
Hi All,

Not been around for a bit and not fired up LW either (using other 3D software at the mo) but interested to hear how the unified sampling has affected image stability in animations, particularly with regards to finer details.

So...anyone with good animation experience who can give me some insight as to how stability compares to the LW9 days?

Some good looking stuff coming in 11.5, so popping my head around the corner. :)

Thanks

David

bazsa73
10-03-2012, 12:15 PM
+1, I would like to know too.

nikfaulkner
10-03-2012, 02:49 PM
I've been tinkering but no solid conclusions or settings yet. I'm working on getting my head around some good generic settings that'll be good places to start. A bit paranoid about noise/buzz/crawl in my final renders.

Had some settings in 9.6 that were my go to for most projects. When I'm in front of my machine Ill post my initial thoughts on the settings I'm using for renders in 11.03 (total trial and error on my part with no real insite) don't know if they'll be of any use.

Cageman
10-03-2012, 03:27 PM
https://www.youtube.com/watch?v=W3sQGjnisz4

For the characters (ingame meshes btw) we had the following settings:

Shading Samples: 3
Light Samples: 2
Min: 4
Max: 16
AS 0.01

The grain in the trailer is a post-effect.

I think we used the same settings on the environment renders, except the kitchen that needed a lot more due being 95% GI+Blury reflections only. :D

In most cases, the average rendertime for a character was around 3-5 min/frame in 720p. The environments were fairly fast as well... maybe 8-10 min/frame (again, except the kitchen). If you are interrested in more specifics I can probably dig them up. Oh and I believe we used LW11.0.1 on that one...

Hope this helps.

dmack
10-04-2012, 01:35 AM
Hi,

Thanks. The video, whilst completely cool, probably wouldn't be the first to show AA issues. It's got motion blur and the movement is fast. I do quite a bit of medical work where there needs to be fine detail combined with slow movement. This is unfortunately a prime candidate for exposing poor AA. A slow detailed scene is the acid test. Modo's AA is pretty rock solid, but I'm interested in a possible return to LW for a fuller toolset and nodal deformations. The AA proved to be a real issue for me in LW9.6, so before I venture back to LW land, I want to make sure that it has fundamentally changed.

Thanks for your input so far guys. Any more?

RebelHill
10-04-2012, 02:07 AM
Nothing's really "changed", at least not in the way I think you're thinking. Getting rid of AA buzz/fizz really just comes down to throwing enough samples at the offending area. LW11s US doesnt provide for any BETTER AA than you have in 9.6, really, what it does do though is provide a much FASTER turn around for it, and gives you much better control for being able to hone in on the areas that need additional sampling without wasting rendertime on portions of the frame that are already clean.

dmack
10-04-2012, 03:17 AM
OK. Yes, got you. Does the demo allow animations to be rendered? It sounds like a try it kind of situation :)

Cageman
10-04-2012, 03:58 AM
OK. Yes, got you. Does the demo allow animations to be rendered? It sounds like a try it kind of situation :)

Yes... the 30-day trial works like a licensed LW. No limitations whatsoever.

kopperdrake
10-04-2012, 04:34 AM
That's not too far off my default settings:

Shading Samples: 2
Light Samples: 2
Min: 4
Max: 12
AS: 0.02

These are my test render settings and on simple textures I can get away with them. More often than not one or more needs tweaking and the highest I tend to go to are:

Shading Samples: 4
Light Samples: 4
Min: 6
Max: 32
AS: 0.01

Most of the stuff I do sit between those two settings, based on texture detail, amount of area lighting (or other 'soft' lights), and motion blur.

dmack
10-05-2012, 06:36 AM
I've started my re-evaulation of LW and something that immediately strikes me is that the AA isn't as good at modo's when it comes to edge of geometry regions. I've got a simple orange sphere on a floor in both modo and LW and there is distinctly more noticeable 'pixel stepping' in LW's render at around the 7/8 o'clock region. I can wham samples at it (min 64 max 256) with an AS of 0.003 and it still doesn't get to the smoothness of modo. Frustrating as this is my first test!

I'm hoping to start using LW11.5 as I like the look of the animation tools (deformation, flocking, particles, soft body dynamics etc) but this has already dented my confidence.

Can any one suggest something I might be doing wrong to put me back on the track?

Hieron
10-05-2012, 06:48 AM
Dmack, plz post that simple test scene. Much easier to get quick feedback.
Got Modo here as well so can check that too.

dmack
10-05-2012, 06:57 AM
I've got the renders, but binned the scenes - will do again and post. In the meantime, here are the renders... You can see the stepping with the naked eye, but zoomed in photoshop reveals properly. I know this is very detail oriented, but it is exactly the type of thing that kills projects - I've been 3D'ing for about 15-20 odd years now and know the pain that comes from flickering renders all too well.

Files let you know which sw was used. I've zipped rather than jpeg'd for obvious reasons!

Cheers

Hieron
10-05-2012, 07:14 AM
Without scenes it is trickier to compare, but surely the LW image is not as nice with AA. Depends on settings like reconstruction filters too though.. it may do a sharpening thing.

We share your concern on AA issues at least and LW is not always ideal there. Rendering with oversampling helps a bit but we have had our fair share of flickering. Low discrepancy should help in some of our moire issues, but actually made it worse and it currently has a bug when used together with OverSampling. It just blurs the image, and that is not what it should do (or does with Classic).

pixelranger
10-05-2012, 07:14 AM
I can wham samples at it (min 64 max 256) with an AS of 0.003 and it still doesn't get to the smoothness of modo.


The problem isn't in the number of samples, but in the type of filter. Try using the same filter as in Modo (Box/Cubic, Triangle, Mitchell, Sinc, CatRom, Cone, Gaussian, etc)

dmack
10-05-2012, 07:19 AM
Here are two scenes. The renders they produce look v similar but when you scan your eyes around the edge of the ball, you'll notice edges that look more likely to flicker in LW than Modo. I'll do some anim tests too.

- - - Updated - - -

OK, will try that. Cheers.

Hieron
10-05-2012, 07:21 AM
And as always, this gem is... amazing:
http://www.neatvideo.com/

can not recommend it enough.

50one
10-05-2012, 07:24 AM
I've got the renders, but binned the scenes - will do again and post. In the meantime, here are the renders... You can see the stepping with the naked eye, but zoomed in photoshop reveals properly. I know this is very detail oriented, but it is exactly the type of thing that kills projects - I've been 3D'ing for about 15-20 odd years now and know the pain that comes from flickering renders all too well.

Files let you know which sw was used. I've zipped rather than jpeg'd for obvious reasons!

Cheers

Had a look at your images and to be fair I don't see anything wrong with LW render at all? To be fair ther's just something weird about the modo render tho where the specular hit is.
But I must admit that modo is a bit faster with getting the "cleaner lines"

Your modo render:108324

- - - Updated - - -

I've been using the Topaz DeNoise for stills, it's the the best thing since slicing bread.

dmack
10-05-2012, 07:24 AM
OK, yes, gaussian seems to be producing much better results. Slight loss of crispness, but you can't have it both ways...so, yes, definitely better...

RebelHill
10-05-2012, 08:40 AM
yeah, different filter and reconstruction patterns play a big role in getting good AA... The basic rule of thumb stuff for what to use where in covered in my US/AA vid on my YT.

Cageman
10-06-2012, 07:55 AM
Yes... LWs AA isn't there yet when it comes to clean edge-AA... in any case...

I made an animated camera in Modo 501 and setup the same in LW. Tweaked the unified settings in LW and found that Mitchel Soft rec.filter is the best one to use, with a tradeoff of not being as sharp on the edges as Modo. I also tweaked the LW-scene so that it renders at the same speed as Modo (approx. 2s / frame).

I rendered out both sequences to 16-bit exr, but for some reason, modo insisted on saving out 2.2mb images where LW images are around 300k. Both of them are the same bitdepth though. Imagesequences as RAR-archives. (http://hangar18.gotdns.org/~cageman/LWAA/)

I've attached the LWS and LXO as well.

dmack
10-08-2012, 02:10 AM
Cool. Thanks for the test. My understanding is that Modo always uses the maximum amount of AA samples on geometry edges. Given that they represent a small number of pixels generally, it seems like a good idea. I wonder though if that's it, or whether the actual AA code needs some improvement? I'll be doing some tests in amongst other features tests over the next few weeks, so I'll post back my thoughts.

Thanks again for your test.

I looked at the youtube video ( http://www.youtube.com/watch?v=8JdONpR6dR8) about AA and the new unified sampling and have to say it's great. So thanks for that tip.