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jaxtone
01-28-2009, 07:02 AM
I just rendered a scene with som cranes in the distance. It seems like whatever settings I use flicker occure in the shadows under the steel rods under the crane!

I have raised the AA and tried different settings with the Treshold and Oversampling options, from 0.01 to 1, but this beats me!

Any suggestions?

Mitja
01-28-2009, 07:37 AM
Is there something that is moving in the scene, apart from the camera?

Lightwolf
01-28-2009, 08:06 AM
Try raising the Rays per Evaluation, maybe double the amount for a start.

Do you get the flicker without GI as well?

Cheers,
Mike

jaxtone
01-28-2009, 08:11 AM
Hi!

In the foreground a big vehicle moves into the Camera and in the background some item moves that you cannot see!


Is there something that is moving in the scene, apart from the camera?

4dartist
01-28-2009, 08:31 AM
I would try these things:

-Double check your geometry doesn't have bad parts, like intersecting polygons or just general bad modeling, because when I've seen flicker on Cached shots, it was around these spots mostly.

-If you have objects moving in the background that you can't see, I would save your scene as a copy to be rendered and delete EVERYTHING in your scene that won't be seen at all during the shot. It may be a hastle but it can simplify things and possible fix the problem.

-lastly, this probably doesn't apply to your shot, but don't use Animated Cache with Deforming Geometry, (I've heard it's unsupported and causes problems)

AA probably isn't going to help GI flicker. It's going to either be fixed by different GI settings, or fixing the geometry.

Another thing you can do is toggle that problem object as 'unseen by camera' Render your shot. Then render that object again alone and composite it back in, I just had to do that on one of my shots on a problem object. Maybe it's something you shouldn't have to do because 'yes lightwave should work like intended' and all that bull **** but the fact is you need to get a shot done, then do it whatever way it takes.

CC Rider
01-28-2009, 01:29 PM
If your camera/objects are moving you're going to need motion blur or you will definitely get flicker probs.
Try the Photoreal MB...I would go 3 to 5 passes depending on the speed of your camera/object movement. Higher passes for faster motion.

:D

4dartist
01-28-2009, 01:35 PM
Wait are we talking interpolated radiosity flicker or AA flicker? Two VERY different things.

What I (and Lightwolf) suggested are things that involve Radiosity interpolated flashing of samples, and what CC Rider is suggesting is more to do with edge/AA issues.

Increasing AA or motion blur or AS will not effect interpolated flicker at all. (from how I understand it)

CC Rider
01-28-2009, 01:48 PM
Increasing AA or motion blur or AS will not effect interpolated flicker at all. (from how I understand it)

That's my understanding as well...

It may well be a combination of both.
You have what appears to be the default settings for GI with no MB and moving objects.
with these settings, I'd be surprised if it didn't produce flicker...

I would have pointed the finger at MB first though just because he is using the Radiosity Cache.

aSkeptic
01-28-2009, 04:26 PM
If you are going to use radiosity in animation you have to use monte carlo or backdrop only with cache and animation checked otherwise the solution will not use the same points (sample points will vary). This causes a flicker in animation.

See:

http://www.except.nl/lightwave/RadiosityGuide95/index.htm

jaxtone
01-28-2009, 04:58 PM
Thanks for your tip but if you look at the image I attached it is definitely Monte Carlo! I am no expert and there might be settings in Monte Carlo e that can be better than my factory solution! But I am not there yet...

Cheeezuz what time fades away when doing all these test renders... there are just too many of them without any extralifes added in your backpockets!


If you are going to use radiosity in animation you have to use monte carlo or backdrop only with cache and animation checked otherwise the solution will not use the same points (sample points will vary). This causes a flicker in animation.

See:

http://www.except.nl/lightwave/RadiosityGuide95/index.htm

jaxtone
01-28-2009, 05:24 PM
Thanks for your input!

I have tried to exclude everything that isnīt seen by the camera but it made no difference! Itīs the same flicker chasing my nuts 24/7...

The modeling of the cranes in the background is low polys in quads, very clean and easy models without any detailed features, and especially not in the particular areas wher the flicker occures...

No, as you said the AA isnīt much of a help here...

Youīre damn right when you say that the shot has to be done whatsoever! But I actually wanna try to find a solution without beginning to rip the scene for part rendered objects for post. At least not yet! But maybe this is the way it has to be done when time is running out!

Thanks for the help!


I would try these things:

-Double check your geometry doesn't have bad parts, like intersecting polygons or just general bad modeling, because when I've seen flicker on Cached shots, it was around these spots mostly.

-If you have objects moving in the background that you can't see, I would save your scene as a copy to be rendered and delete EVERYTHING in your scene that won't be seen at all during the shot. It may be a hastle but it can simplify things and possible fix the problem.

-lastly, this probably doesn't apply to your shot, but don't use Animated Cache with Deforming Geometry, (I've heard it's unsupported and causes problems)

AA probably isn't going to help GI flicker. It's going to either be fixed by different GI settings, or fixing the geometry.

Another thing you can do is toggle that problem object as 'unseen by camera' Render your shot. Then render that object again alone and composite it back in, I just had to do that on one of my shots on a problem object. Maybe it's something you shouldn't have to do because 'yes lightwave should work like intended' and all that bull **** but the fact is you need to get a shot done, then do it whatever way it takes.

aSkeptic
01-28-2009, 05:31 PM
Thanks for your tip but if you look at the image I attached it is definitely Monte Carlo! I am no expert and there might be settings in Monte Carlo e that can be better than my factory solution! But I am not there yet...

Cheeezuz what time fades away when doing all these test renders... there are just too many of them without any extralifes added in your backpockets!

I'm not a radiosity expert either. Sigh, hope you get this figured out. If all else fails you could bake the illumination of the crane to a texture map that should stop the flicker cold. Not an elegant solution I know.

jaxtone
01-28-2009, 06:00 PM
Short and small clip that shows what happens! The film is just rendered in a very small image size "174X200 pixels" and this might be the best size to watch it as well! Itīs not a full screen image!


Render settings TTS TOC 2008-2009

Size 688X504

RENDER GLOBALS
Filtering: Classic High

Global Illumination:
Monte Carlo

Interpolated

Blur Background

Cache: Automatic

Animation: 1 Frame Step

CAMERA PROPERTIES
Persp. Cam
Foc Length 24.0 mm
Zoom Factor 3.2
FoV 46.2 X 34.71
Width 688
Height 504
Frame Aspect Ratio 1.365
Segments 1

Antialiasing 16
Reconstruction filter: Classic
Sampling PAttern: Fixed
Adaptive Sampling ON
Treshold 0.8
Oversample 0.7

No DOF or Motion Blur

aSkeptic
01-28-2009, 06:14 PM
Have you tried turning off adaptive antialiasing? The areas that are flickering are of close contrast...

CC Rider
01-28-2009, 07:00 PM
Is there a reason why you don't want to use motion blur?
Nearly anything that has camera or object motion will need some form of motion blur to look realistic (and not flicker...)

:D

CC Rider
01-28-2009, 07:06 PM
I take it back...after looking at your clip (which is very short...) looks more like a radiosity issue. Try lowering minimum spacing to 1.0 / maximum to 4.0. RPE at least 100 or more and secondary rays around 25-50 and use at least 2 bounces.
Make sure the path for the radiosity cache is valid too.

Good luck!
It's a pretty cool model.

Also consider the advice of rendering the motion elements separately from the static ones and composite elements together. Good Advice!

:D

jaxtone
01-29-2009, 04:16 AM
I actually tried with MB but it made the situation even worse. When trying different levels of MB the shades on the distant wenīt mad! Then they started to jump up and down like toads on crack! :)

I am sorry but I had to make the clip that short of two reasons, first of all becuase I didnīt want to add any compression on the sampled clip! And secondly because the file limit size is 5 MB for all forum attachements, (at least as I have understood it so you may correct me if I am wrong here!) But I hope you still could get a slight opinion of whatīs going on in the distance of this minimized film clip!



Is there a reason why you don't want to use motion blur? Nearly anything that has camera or object motion will need some form of motion blur to look realistic (and not flicker...)

:D

walfridson
01-29-2009, 05:18 AM
Maybe you should try what aSkeptic suggested, baking to UV textures. Check out the surface baking camera.

jaxtone
01-29-2009, 05:21 AM
Maybe you should try what aSkeptic suggested, baking to UV textures. Check out the surface baking camera.

Hmmm... are there any information about this. I guess itīs dead simple but I actually couldnīt find any simple explanation to this! Any suggestions?

jaxtone
01-29-2009, 05:29 AM
Fragrience, what word is that? Thought it was spelled fragrence? Well one day you will possible have a chance to change the headline in your messages! :)


Now back to the flicker problem... I know exactly how I should have done this... but ainīt got the right tools since Evasion outrun Vista 64 bit solutions!!! Grrrrrrrrrrhg!

If I could get my hands on a superfast DOF plugin that were dedicated for the distanced area in the background where the flicker occures, this would have been a piece of cake to solve! I have tried iDOF, Autofocus and a few others but damn they are sooooo slow, I really miss XDOFīs fast and accurate post blur in situations like these!

Maybe there are some rocket science guys out there that have alternative solutions for fast and high quality post DOFīs that can be activated and used for issue like this!

P.S. I donīt find an option in Lightwaves own DOF since itīs to damn slow when you add GI!

walfridson
01-29-2009, 05:41 AM
ftp://ftp.newtek.com/products/LightWave/Trial/Videos/Baker.mov

I haven't watched it, hope it's good :)

aSkeptic
01-29-2009, 06:37 AM
The video walfridson linked does exactly whats being discussed. The only thing else you'll need to know is how to make a uv map and the kind of projection that would be the easiest would be atlas. The real thin parts of the crane may need very large maps to get the details right but being in the background lessens this requirement a bit.

jaxtone
01-29-2009, 07:26 AM
Thanks for the link and additional information guys!

Thereīs one thing I donīt understand:

Since my object already have specially designed UV maps for transparancy parts and some other issues on the main item itself, how is it possible to create UV maps on UV maps for the Surface Baking camera?

Meaning that there must be some kind of conflict with the default UV maps that comes with the object and the new ones you suggest me to create in Atlas!


The video walfridson linked does exactly whats being discussed. The only thing else you'll need to know is how to make a uv map and the kind of projection that would be the easiest would be atlas. The real thin parts of the crane may need very large maps to get the details right but being in the background lessens this requirement a bit.

aSkeptic
01-29-2009, 07:37 AM
Thanks for the link and additional information guys!

Thereīs one thing I donīt understand:

Since my object already have specially designed UV maps for transparancy parts and some other issues on the main item itself, how is it possible to create UV maps on UV maps for the Surface Baking camera?

Meaning that there must be some kind of conflict with the default UV maps that comes with the object and the new ones you suggest me to create in Atlas!

Well if your current uv maps have full coverage of your model you can use them. But theres no reason you can't have multiple uv maps covering the same geometry. Just have a uv map dedicated to baking the color and illumination to a texture and apply the texture to that uv map in the surface editor in the color channel, set luminosity to full and take out all diffuse. At least I think thats how its done I haven't done it in a while.

So you could have a uv map for transparency and have it work side by side annother uv map for the placement of a baked texture.

walfridson
01-29-2009, 07:45 AM
http://homepage2.nifty.com/nif-hp/index2_english.htm
If you go with uv atlas and baking I recommend plg's uv chart packing plugin. Check his sample.

praa
01-29-2009, 11:54 AM
try using classic camera with medium enhanced AA

jaxtone
01-30-2009, 03:06 AM
Ok!

Iīll give it a shot! Is this a known problem with the perspective Camera?


try using classic camera with medium enhanced AA

Mitja
01-30-2009, 03:11 AM
Ok!

Iīll give it a shot! Is this a known problem with the perspective Camera?

Actually not, should work more than fine with the perspective camera. The classic camera is slower and doesn't work with PR motion blur.

jaxtone
02-01-2009, 05:39 AM
Thank you Mitja!

The more I am thinking about it itīs obvious that a real fast and smooth Lightwave "post blur" plugin would have made this solved in minutes!

The ones that are available at the moment for Vista 64 bit is "slow" and do not work as expected when you wanīt something done before father christmas retires!

Xdof havenīt any valuable information of when they will release a 64 bit solution and that makes me so... "freaking pissed"!


Actually not, should work more than fine with the perspective camera. The classic camera is slower and doesn't work with PR motion blur.

toby
02-03-2009, 02:33 AM
From the tiny clip it's hard to tell, but this looks more like aa flicker than gi flicker (even though 64 rpe is extremely low). There is no flicker in the shadows near camera, and where it is flickering you have fine lines that are very close to perfectly horizontal/vetical, a common cause of aliasing. Try turning off Adaptive sampling while raising aa to 25, and use Gaussian reconstruction instead of classic.

You should be able to render two adjacent frames of the animation, and toggle between them, to see if there's an improvement - so you won't have to render the enitre scene just to find out what works.

jaxtone
02-03-2009, 12:31 PM
You might be right and I will try that as well!

P.S. Donīt you think itīs strange that there isnīt even a tiny DOF plugin that could solve this problem in a fast and accurate way? D.S.

Thanks for the link to the clip! It was really touching to see Sean Pennīs declaration from the depth of his heart when he revealed the truth and grief that many Americans have to live with! I have earlier seen Matt Damonīs interview about Sarah Palin:

Matt rips!
http://se.youtube.com/watch?v=6MJCvHMtwE4&feature=related

Matt Damonīs well educated, polite and have all the right in the world to reveal his thoughts of how wrong he thinks the brand of U.S. is presented to the rest of the world nowadays! To me America is exciting, beautiful and scary at the same time!

When talking about americans... arenīt the real natives forced to live in reservations like Casinos nowadays! :D


From the tiny clip it's hard to tell, but this looks more like aa flicker than gi flicker (even though 64 rpe is extremely low). There is no flicker in the shadows near camera, and where it is flickering you have fine lines that are very close to perfectly horizontal/vetical, a common cause of aliasing. Try turning off Adaptive sampling while raising aa to 25, and use Gaussian reconstruction instead of classic.

You should be able to render two adjacent frames of the animation, and toggle between them, to see if there's an improvement - so you won't have to render the enitre scene just to find out what works.

toby
02-03-2009, 04:38 PM
Can't you use a little photoreal dof in the perspective camera? With that little dof it shouldn't need a very high setting nor take very long to render. I don't like the idea of blurring things just to fix or hide errors, but it is pretty far in the distance and cg can be too sharp for that. Gaussian filter gives you a fair amount of blur though, you probably don't need both.


You might be right and I will try that as well!

P.S. Donīt you think itīs strange that there isnīt even a tiny DOF plugin that could solve this problem in a fast and accurate way? D.S.

Thanks for the link to the clip! It was really touching to see Sean Pennīs declaration from the depth of his heart when he revealed the truth and grief that many Americans have to live with! I have earlier seen Matt Damonīs interview about Sarah Palin:

Matt rips!
http://se.youtube.com/watch?v=6MJCvHMtwE4&feature=related

Matt Damonīs well educated, polite and have all the right in the world to reveal his thoughts of how wrong he thinks the brand of U.S. is presented to the rest of the world nowadays! To me America is exciting, beautiful and scary at the same time!

When talking about americans... arenīt the real natives forced to live in reservations like Casinos nowadays! :D
Yea, I think I've met one american indian in my lifetime, when I was a kid. I've met more people from indonesia than that. Damn shame, they're free to leave the reservations, but I guess they don't want to see their heritage watered down and/or can't afford to move.

jaxtone
02-03-2009, 05:00 PM
Indian Native Prophecy:
http://se.youtube.com/watch?v=ULjuoW9Z6ag
http://se.youtube.com/watch?v=aEQK77yjEAc&feature=related
http://se.youtube.com/watch?v=81CnWaj8980&feature=related
http://se.youtube.com/watch?v=Dr43dW2heh4&feature=related
http://se.youtube.com/watch?v=ox51PCqdyy0&feature=related

Cheers!


Can't you use a little photoreal dof in the perspective camera? With that little dof it shouldn't need a very high setting nor take very long to render. I don't like the idea of blurring things just to fix or hide errors, but it is pretty far in the distance and cg can be too sharp for that. Gaussian filter gives you a fair amount of blur though, you probably don't need both.


Yea, I think I've met one american indian in my lifetime, when I was a kid. I've met more people from indonesia than that. Damn shame, they're free to leave the reservations, but I guess they don't want to see their heritage watered down and/or can't afford to move.

Mitja
02-04-2009, 01:34 AM
DOF - if you have a comp software, render out a zbuffer pass and do your dof later (AE lens blur), this way you can speed up render times and see if this could solve the issue.

jaxtone
02-04-2009, 07:33 AM
Thanks for the advice! Yes, I have comp softwares and I know about the zbuffer pass! I actually prefere working with blur and stuff in post and thats how I done it earlier!

But in some cases you just want to see improvements in your software as well and for this particular problem a fast and accurate DOF plugin would have been perfect! My question is still connected to this: Why isnīt there any fast and good DOF pluging for Lightwave 9.6 on Vista 64 bit systems?


DOF - if you have a comp software, render out a zbuffer pass and do your dof later (AE lens blur), this way you can speed up render times and see if this could solve the issue.

toby
02-04-2009, 01:31 PM
There's a *lot* of plugins not available for 64bit yet.

What's wrong with the Perspective camera dof?