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03-24-2011, 04:53 AM
Now we've got LW10 running smoothly, we're starting to do sexy exterior & interior Architetural walkthrough animations with HD instance, HDRI sky, domelight sun & Radiosity.
I can get it to look pretty good, BUT it's toooo slow - 2 hours a frame on the farm at 960x 540 when I need 1 hour maximum at 1280x720.
I started with some settings advised in another thread & tweaked them a bit, & the lighting is smooth across the animations, but I really can't work out what to try to tweak & by how much.
There are so many variables I don't know where to start, and it takes 4 hours on the farm before I can check what each tweak has done
Anyone got any advice ?

Current settings:
ticked are;
Final Gather
Interpolated
Volumetric Radiosity
Intensity 200%
IB 4
RPE 64
SBR 32
AT 22.5
MinPS 3
Max PS 100
Multiplier 50%
Cache ticked
PreProc Auto
Frame Steps 25
Scene Baked

Camera is AA 3 (could do with at least 5!)
Mitchell Sharp
Fixed
no AS

Ryan Roye
03-24-2011, 05:49 AM
I know caching isn't one of them (freezes the light... use for non-moving elements). I've been wondering about this myself as my latest content actually has radiosity-rendered scenes in it... with mixed results.

I did see something about "baking" a radiosity scene... but I haven't experimented with it. 4-6 minutes per render in low resolution settings make meaningful experimentation for animation hard.

JonW
03-24-2011, 06:18 AM
Are you Baking the radiosity? & is the render without the radiosity 2 hours a frame?

A side issue, how long does an f9 render take, Radiosity? & actual Rendering? If f9 a lot quicker the Radiosity Cache is probably not being found rendering via the farm & then it's being re-done for every frame.



SBR 16 is usually enough.

Multiplier, For an animation 100% is better but if you can get away with 50%, good!
AA 5, 9, 17, 33, 65 etc gives you a better jump in quality if you are already doing say 4, 8, 16 etc.

MinPS I usually go for 1 but if you can get away with 3, good!

RRL keep this as low as possible. it only needs to be 1 higher than the number of transparent surfaces you have that will line up. This can save a lot of time.

Get rid of reflective surfaces that really don't give any benefit being reflective.

Area lights on higher quality add to render time. avoid going above 5.

Remove things from the scene that are not seen.

Coloured lights rather than white lights add time.

If you have trees use much lower RPE 12 - 24, SBR 4 - 8


Some good points by Mr Rid.
http://www.newtek.com/forums/showthread.php?t=115566

03-24-2011, 06:50 AM
Scene is being baked at 25 frame intervals - with only camera moving this seems to give me flicker free animation - unbaked is unusable - cache definitely being found
Without radiosity there is almost nothing to see - would have to re-light massivly
Currently only using HDRI sky image (created with Ozone) and one dome light
RRL currently 6, have now clip-mapped HD instance foliage (UV) so may get away with lower.
Unfortunately quite a lot of reflective surfaces specified (stainless steel, glass, polished marble - quite a lot of reflection blurring too!

Sounds as if I'm on the low side of the advisable settings already !

Biggest pain is that someone in the studio is doing stills for same project in MAX/MentalRay with sod-all effort to set up lighting and getting similar looking images 4x the pixels in 40 min (though we don't know how well that would work in an animation!)

Ryan Roye
03-24-2011, 08:36 AM
Thanks for the great tips JonW!

ingo
03-24-2011, 10:51 AM
Hmm, can you show us a picture and your comp specs, would help a lot. I am not sure about the domelight for the sun, try a simple distant light and compare the rendertime.

Just read your comment, reflection blur is a killer too, how many samples do you use ?

gordonrobb
03-24-2011, 11:14 AM
IF the only thing moving is teh camera, why don't you just bake the scene radiosity and use that? why every 25 frames? Also, have you tried less AA and more AS? Plus which camera are you using? Make sure its the perspective one and not classic.

JonW
03-24-2011, 03:23 PM
Are you Baking the radiosity? & is the render without the radiosity 2 hours a frame?

A side issue, how long does an f9 render take, Radiosity? & actual Rendering? If f9 a lot quicker the Radiosity Cache is probably not being found rendering via the farm & then it's being re-done for every frame.


Sorry to ask again as you have said RC is being found. But if it is not being found LW will redo it for each frame. This will add to your render time.

Is Radiosity Cache on the farm working? You can easily tell apart from the time compared to an f9. If you run WTM on some to the farm computers you will see the 2 distinct patterns in the CPU usage! So many people have had problems with RC & have not been aware of it &/or think it's ok, but it's not ok!!!

How long did Baking the radiosity for the animation take. (For one of my 30 sec FlyT it took 12h on my W5580 for every frame, this was the quickest overall way to go, & each frame could just get on & render, "remember to lock the radiosity". I even started rendering the first frames on all computers while the remaining radiosity was being baked & once baked, replaced the partly done radiosity file with the complete radiosity file & then got the W5580 onto the the farm as well. The x55/x56 CPUs are beasts for baking radiosity!)

You can also add to the Radiosity Cache file to fill in some of the frames. You can also use different cameras if you wish.


A large still image one can render just as quick as a animation frame. You can get away with murder with your settings because by nature it's only 1 image! & they will most likely scale it up 30% or so in PS & the render will look better this way as well, not too sharp edges.



ingo: Hmm, can you show us a picture and your comp specs, would help a lot. I am not sure about the domelight for the sun, try a simple distant light and compare the rendertime.

Just read your comment, reflection blur is a killer too, how many samples do you use ?

Reflection blur is a killer! An image etc will help a lot!


Some of your reflected surfaces maybe obvious in a still but in a flyT it won't really be that obvious as your camera has moved on & the viewer is distracted by the flyT as a whole. We tend to get a bit fixated on detail in flyTs to our own expense which the viewer will not be aware of in hell or high water, which just adds pointless render time!


If all else fails, Garagefarm is one of our own with good rates. But I would try to optimise the scene first regardless of which computers you use.

03-28-2011, 11:19 AM
I'm getting it down a bit with adjustments to Ray recursion & softened reflections,
But regarding the idea that 'if only the camera is moving' you could bake radiosity differently, like, how?
AFAIK radiosity cache is only ever added to for polygons that can be seen by the camera, if I just bake one frame I get flickery solutions as soon as more stuff gets seen be the camera; as long as only the camera is moving, and slowly at that, I can get away with only processing every 25th frame.

JonW
03-28-2011, 02:37 PM
As long as the camera is moving, no lights changing either, it's going to be quicker. Radiosity needs to be done to surfaces that are not seen, you may see a part of a surface in one frame but not in another frame. I found it better to bake a rough, say every 20 to 25 frame or so. Then redo the remaining frames. Also keep RPE fairly low as you will get a RC file out of control. Once you have baked the Radiosity lock the Preprocess "Locked". I use the "Use Behind Test" as well.

If your radiosity is not looking good make sure you Clear Radiosity Cashe. It's not going to help keeping adding to a dodgy cache file. Or if you change things in the scene clear the cache.

The Radiosity is something different for every scene. Well before the end of the project I will bake a radiosity file overnight & see how it's looking. So when I get to the final render stage I've got me settings for my final bake all sorted out.

Attached is a large scene originally rendered 640 wide, a frame on a 920 ranged between roughly 20 & 60 minutes to render. The only flickering here is due to compression, the frames do not have any. The RC file was about 300mb & the scene was about 5gb, there was a lot of other stuff in this model which I should have removed.

Danner
03-28-2011, 03:56 PM
This sequence was rendered in under 2 minutes per frame at 720p HD.

It was lit using 6 shadow mapped spot lights with 2048 resolution and shadow cache on. A gradient backdrop with overbright values, the tinted glass dome was hidden from radiosity so light could get through.

Radiosity settings:
Indirect bounces 2
RPE 500
secondary bounce rays 50
Min pixel spacing 3
Max 50
Cache on and locked. (pre rendered at 15 frame step, took around 10 min for the 1000 frames)

Camera settings:
Perspective camera
Antialias 3
adaptive sampling .03
Oversample .5

Cageman
03-28-2011, 04:27 PM
This sequence was rendered in under 2 minutes per frame at 720p HD.

Sorry, but could you tell us what computerspecs you have? Without knowing what type of processor you have, rendertimes / frame isn't saying anything.

:)

Danner
03-29-2011, 01:37 AM
it's a 2.5 year old dual Xeon system E5430 @ 2.67ghz.

JonW
04-15-2011, 10:12 PM
This sequence was rendered in under 2 minutes per frame at 720p HD.

It was lit using 6 shadow mapped spot lights with 2048 resolution and shadow cache on. A gradient backdrop with overbright values, the tinted glass dome was hidden from radiosity so light could get through.

Radiosity settings:
Indirect bounces 2
RPE 500
secondary bounce rays 50
Min pixel spacing 3
Max 50
Cache on and locked. (pre rendered at 15 frame step, took around 10 min for the 1000 frames)

Camera settings:
Perspective camera
Antialias 3
adaptive sampling .03
Oversample .5


Looks almost identical to this.

Hieron
04-16-2011, 05:28 AM
Without seeing an actual render of the shot you are working on, nor computer specs. I believe with those GI settings, it's not the radiosity that's giving the issues.

It's the rays being cast. The domelight and blurry reflections being the biggest suspects. In a thread from Tobian there was great info on stopping reflection rays (or their blurring ) after n bounces etc.

Also, why wait 4 hours? Use a very small limited region and take that from 1 minute to 10 seconds or something. Workflow speed is everything. Unless your F9 render is blazing fast already, why use the farm to check tweaks? That's madness..

-> But again, who knows without seeing what you are working on or the pc you use. <- (this goes for OP too Cageman! :P)

ps: Like Jonw said, do check to see if the renderfarm is seeing the RC file though. Since LW10, I have to manually edit all my scene files to change directory, as it is being incorrectly saved and subsequently opened by lwsn.exe. Like Jonw suggested, a comparison of F9 and lwsn.exe renders would show this. Easiest is: small limited region, tweak it to be very fast, bake only that small region of max 5 min rendertime total. And send that off to lwsn.exe to render on 1 node (is 1 frame anyway) and compare to F9. Also manually check with notepad in the .lws file if the radiosity directory is correctly listed and change it to a full path to be sure. Don't wait hours..

Danner
04-16-2011, 09:36 AM
Looks almost identical to this.

Glad you think so, because that is exactly what it is. It's the "rotonda" room at the Westin Palace in Madrid.

Hieron
04-16-2011, 11:43 AM
Heh Danner, nice shot. Especially considering the 2 minutes rendertime.