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fabmedia
03-04-2004, 02:29 PM
I'm about to render out a scene for TV at NTSC and I was wondering about how many AA passes I would need, and whether I should use adaptive AA or Enhanced?

Does the NTCS format need to have the pixel ratio (.9) if it's going to be edited with software like Premiere? Or does that ratio only matter if it's going straight to tape. I couldn't find anythiing in the manual.

Oh and can I render at 29.97 without field interlacing and allow FinalCut Pro to interlace on the fly, or am I asking for problems? I've read somewhere that enhanced medium, normal motion blur, and field rendering should work. But my question still stands to be answered.

Oh and how long should a render take for a frame 10 minutes?

Triple G
03-04-2004, 04:18 PM
I rarely, if ever, use fields. When I'm doing stuff for my demo reel, for instance, I usually render to D1 NTSC, Enhanced Low, and turn off adaptive sampling. If you have really noisy textures you could use a gradient based on camera distance to fade out the textures so that you don't get the flickering. I'll then usually add some motion blur in After Effects, then bring it into iMovie to export to tape. Haven't had any noticeable issues with this workflow yet.

This is what works for me...your mileage may vary. :)

fabmedia
03-04-2004, 04:24 PM
Do you keep a pixel ratio of 1 or the default of .9? I use iMovie everyonce in a while, but never for video output to tape. AND do you ever output to DVD, if so how's the quality?

Triple G
03-04-2004, 04:54 PM
If you're going to wind up viewing it on a TV screen (NTSC), you want to render from Lightwave with a 0.9 PAR. Just select the D1 NTSC preset in the camera properties and you'll be all set.

I really only use iMovie for outputting to tape...once in a while if I need a quick and dirty edit of something, I'll use it...but most of the time I go straight from Lightwave into AE, and do any editing/compositing/effects work right there. Unfortunately, I don't have a DVD burner, so no...I've never used it for that purpose. If I was going to do that, I'd probably pony up for Final Cut and DVD Studio Pro.

Beamtracer
03-04-2004, 05:20 PM
Originally posted by fabmedia
Oh and how long should a render take for a frame 10 minutes? Render a single frame and see how long it takes. Then you can multiply that by the number of frames in your animation and you'll find out approximately how long it will take (it gives you a rough idea).

So, how long it takes depends on how much time you have! I often render overnight and make sure it will be finished by 9am the next morning. I reduce features in the scene to make sure it gets done in time (ie, you don't use radiosity if it's going to take a week to render!).

Triple G
03-04-2004, 05:49 PM
It's really hard to estimate like that....but what Beam suggested is about all you can do.

Know that if you've got volumetric effects like Hypervoxels enabled, it's going to take longer to render the closer the camera gets to them, so your render times per frame could vary significantly over the course of the animation as a whole.

fabmedia
03-04-2004, 06:27 PM
So I should keep the .9 ratio. Now what if I want to take that footage and use it for CD or internet download. Then I have a deformed image. Can I compress the image so that I lose the .9 ratio. What about I movie? I noticed that when you import an image, it looks like it should while it's being edited. Is it me?

So to recap... Enhanced Low AA (no adapative sampling), Normal Motion Blur, no Interleaved frames at 29.97 fps.

Ya?

Noclar7
03-04-2004, 06:59 PM
I hate to be the alter opinion here but. If you are going to broadcast beta output. I would render interlaced frames if:

a. there is alot of motion in the scene
b. there is not a lot of composting/image correction to be done after the renders.

Reason. interlaced frames are twice as smooth as full frames on standard interlaced television scenes. you are actually viewing approximatly 60fps.

So with that said, if points a & b fall into play, go interlaced. Check it out, it makes a difference.

fabmedia
03-04-2004, 07:05 PM
Well there is going to be a fair bit of motion, a flyby of a ship with missles and guns a blazing with FX compositing.

So are interlaced needed? I'm going to be using iMovie and Combustion to do this...

Triple G
03-04-2004, 07:19 PM
In general options in Layout, keep your fps set at 30. Render out your image sequence at D1 NTSC, 0.9 PAR.

I just checked, and it appears that iMovie will correct your clips so that they don't appear squashed when you're working on them. However, when you export to camera, it will maintain the 0.9 pixel aspect so that it looks correct on your TV monitor.

If you want to display the same video on the web, you'll need to specifically tell it to export the movie at 640x480 (or something else with a 4:3 aspect ratio), in order to correct the stretching.

Triple G
03-04-2004, 07:27 PM
Originally posted by Noclar7
interlaced frames are twice as smooth as full frames on standard interlaced television scenes. you are actually viewing approximatly 60fps.

Some people like the look of interlaced footage...personally, I don't. I think it looks too smooth. Gives things a very "video" feel....sorry, don't know how else to describe it....(as opposed to a more film-like look of non-interlaced with motion blur...but as I said, I prefer to add my blur in post...LW's motion blur is generally too slow and not of sufficient visual quality for my tastes.)

But anyway, try it out and see which you prefer. Like fabmedia said though, pretty much any post-processing you do on the interlaced footage will destroy the fields, so that's another reason why I tend to steer clear of interlacing.

fabmedia
03-04-2004, 07:43 PM
I noticed that if i take in an image at 720x486 in iMovie that I have a black line at the top of the screen. Mind you I guess I shouldn't be importing stills into it.

So non-interlaced, 720x486 .9 pixels, motion blur normal, enhanced low AA non adaptive...

Would dithered motion blur be a good add on or is that just wasting time, AND what about enhanced medium?

fabmedia
03-04-2004, 07:48 PM
Originally posted by Triple G
I prefer to add my blur in post...LW's motion blur is generally too slow and not of sufficient visual quality for my tastes.

So how do you do that? What plug;-in?



Any post-processing you do on the interlaced footage will destroy the fields, so that's another reason why I tend to steer clear of interlacing.

Hmmmm... Now why would that be?

Triple G
03-04-2004, 07:51 PM
If you've gotta do your motion blur in Lightwave, dithered is really the only acceptable option, though it will add significantly to your render times.

Do yourself a favor, though...since you've got Combustion, pick yourself up a copy of ReelSmart Motion Blur (http://www.revisionfx.com/mblur.htm). Some of the best 90 bucks you'll ever spend, if you plan on doing a lot of animation. The blur quality is infinitely better than anything LW can currently produce, and it's a helluva lot faster as well. :cool:

fabmedia
03-04-2004, 09:26 PM
Okay so if I have enhanced AA and motion blur, it's going to take the same amount of time to render is it not?

toby
03-04-2004, 09:35 PM
I personnally prefer Enhanced Med. AA - the difference between Low and Med. AA is pretty clear - Normal motion blur looks fine with Med. and renders much faster than dithered.

A lot of this is personnal preference and how much time you have to render, like Beam said, do some tests.

And if you want interlaced, isn't it much better to do that in post? You can change it to odd or even without re-rendering -

I'd be interested in learning about motion blur in post too, do you need the production bundle if you have AE?

Triple G
03-04-2004, 09:39 PM
I think I understand what you're asking:

Will normal antialiasing + dithered motion blur take the same amount of time to render as enhanced antialiasing + normal motion blur?

There's no real easy way to predict that sort of thing. The only thing I can tell you is to experiment with some test renders...see what works and what will give you acceptable results in a reasonable amount of time.

Triple G
03-04-2004, 09:54 PM
I honestly can count on one hand the number of times (less than two fingers, actually :p ) when I've been involved with a project where rendering from Lightwave with fields was involved. It was a p.i.t.a. and it looked odd because it was the only shot that was interlaced...the rest of the shots in the sequence were not...it stood out like a sore thumb. Basically I've never had a need to use it, and when I have used it, I have been less than impressed with the results.

Medium AA is great...if you can afford the render hit. Most of the time, I find that Enhanced Low is fine for broadcast work, and the slight increase in visual quality of Medium is not worth the extra render time.

And Toby...no, you don't need the production bundle to use that plug I linked to. Just apply it to your footage, and 90% of the time, it looks great at the default settings. You get better looking motion blur in a fraction of the time.

fabmedia
03-04-2004, 09:58 PM
Actually now that you mentioned that, and considering that I'm relatively new to combustion I did notice that there is a motion blur within the program itself.

Now whether motionblur in LW really adds the time on...

fabmedia
03-04-2004, 10:10 PM
Welll currently I'm looking at 17 minutes per frame with Enhanced Low, and 12-15 seconds of animation. Ugh...

toby
03-04-2004, 10:22 PM
Whenever possible use reflection maps and shadow maps instead of raytracing, for faster renders.

If you are raytracing reflections, turn down the ray recursion limit. A setting of 2 will get you 1 reflection bounce, sometimes it's all you need.

fabmedia
03-04-2004, 10:26 PM
Yeah I have my ray recursion set at 2, as I always do. But heck if I can't figure out why it's takiing so long. There's not much in the scene 35 objects and 812, 000 polygons....

toby
03-04-2004, 10:37 PM
other things to try are subdivision levels, make sure they're no higher than they need to be, make the display level the same as the render level, and try different numbers of render threads.
Volumetric lights are a real killer if you're raytracing shadows at the same time.

What's your computer?

fabmedia
03-04-2004, 10:42 PM
No volumetrics and no subdivision objects.

I have a helicopter sitting on the deck of the boat, and another flying past and they total only 60,000. There are static people on the deck of the boat, I'm not too sure how many polys then the boat itself. I'm using HV but only as sprites and they don't take any time to render.

Dual G4 867 with 1.12 Gb RAM and a hell of a speaker system for my DVDs.

Although, I noticed that reflection blurring is on for the water and a couple of other things. 2% here 5% there...

fabmedia
03-04-2004, 10:50 PM
So I got rid of the blurred reflections... and now I'm at 10 minutes medium AA no motion blur...

http://142.173.127.220/boat.jpg

toby
03-04-2004, 10:50 PM
Reflection blurring takes a long time if it's raytraced, try a render without it - you can also render it as a separate pass and blur it in post

- nevermind :D

fabmedia
03-04-2004, 10:52 PM
I've been having trouble with the seperate passes and compositing them. How do you do it? I just end up with a bunch of muddied mess...

fabmedia
03-04-2004, 10:56 PM
BTW Adaptive sampling or no?

toby
03-04-2004, 11:35 PM
I usually leave Adaptive sampling on. I'll go to the next higher AA level before I turn that off -

Render a good pass with no reflection, then turn off what you don't need for reflection and render the reflection pass using 'Render buffer export' under 'image filters'.

In After effects put the reflection layer on top and change it's blend mode to 'screen'

Triple G
03-05-2004, 12:14 AM
Adaptive sampling basically gives you a quicker render at the price of less accuracy and the chance of visual anomalies. Most of the time it's not too bad and you can leave it on, but if you notice you start getting crawly textures or other strange artifacts, you're probably better turning it off.

Avebeno
03-05-2004, 12:45 AM
Maybe this was missed- If you are going to output to DV footage (i.e. iMovie), make sure to set your image size to 720 x 480. You'll have problems if you use 720 x 486. You'll still want an aspect ratio of .9 for the pixels.

Triple G
03-05-2004, 12:50 AM
Good point...I usually just scale or crop it down to 480 in AE before bringing it into iMovie for output to tape.

fabmedia
03-05-2004, 10:09 AM
okay... here's a sample. There's lots of things to fix like the wake in the back, but take a close look. I used adaptive sampling at enhanced Low AA no motion blur.

http://142.173.127.220/ship_webblur2.mov

I notice some flickering at the bow (front) of the ship.

toby
03-05-2004, 12:08 PM
Are you using Skytracer? You can render one image from Skytracer and use it as a background, turn Skytracer off and save tons of time.

The side of the ship looks a little too reflective ( I guess that's why you were softening it ) , and any Lightwaver can spot the Crumple texture in the water, you might want to mix it up a little - I dig the watery-wet deck look, overall it looks really cool

fabmedia
03-05-2004, 01:20 PM
There's no skytracer it's textured environment. I know about the water. I have adjust that. But did you notice the flickering at all at the bow? Should I be concerned about that?

toby
03-05-2004, 08:30 PM
It was pretty subtle, I only noticed it when I looked for it. I'd look at it again but the link's busted

fabmedia
03-05-2004, 08:40 PM
Here it is... my IP changed...

http://142.173.122.222/ship_webblur2.mov

I know it's subtle (I'm a picky graphic designer) but I'm wondering if it will cause any problems...

BTW how is it?

toby
03-05-2004, 08:59 PM
Tiny lines like that will always give you problems, even with Extreme AA. I just watched Pirates of the Caribbean on a TV and there was horrible artifacting on one of the houses' moulding as the camera panned by (it wasn't there at full res) - I wouldn't worry about it, but if you still do you'll have to do something drastic like blurring that portion of the video, or making the railing much fatter.

It's looking great fab

fabmedia
03-05-2004, 09:16 PM
Well, I've come to the conclusion right now, without the HV the scene renders out at 3 min 14 sec. AND I have to add more particles at a smaller particle size. So I think I'll composite these on top fo the ship. Do you know how I should go about creating the alpha for the particles?

As it is, the boat and helecopter are to scale...

I also have an Ambram M1A1 tank coming and an aircraft carrier with jets taking off and landing.... Oh what fun!!!

BTW do you think that something like this would land me a job with a studio?

Avebeno
03-06-2004, 12:45 AM
Are you using motion blur?
Setting motion blur to normal may help this situation a bit.
Perhaps a medium setting. Try giving that a test.

fabmedia
03-06-2004, 10:05 AM
No there's no motion blur. I'm going to do that in post production. It saves me about 10 minutes in render time. Now I seem to be getting a much better result with Enhanced Medium AA with adaptive sampling. With just the boat and water with no HyperVoxels, my render comes in at about 4min 30sec.

I'll post a sampliing of the enhanced medium render later today.

Avebeno
03-06-2004, 10:14 AM
Using motion blur may eliminate the color banding at the bow of the ship. If you blur in post, you'll probably just get blurred color banding.

fabmedia
03-06-2004, 10:34 AM
can you just render out reflections and nothing else or do you have to render the whole scene which the reflections are on?

toby
03-06-2004, 11:50 AM
You have to render the whole scene. But you can go through and turn off other things that slow down the render, and you probably don't need as much AA

toby
03-06-2004, 12:35 PM
Can't say I'm impressed by ReelSmart motion blur in post - I tried all the settings, they only turn the blur up or down - these objects are moving from right to left, and rotating opposite directions

Lightwave, normal blur 50%:

toby
03-06-2004, 12:37 PM
and Reel smart - the blur doesn't seem to go in the same direction as the movement

fabmedia
03-06-2004, 02:36 PM
Combustion has it's own motion blur and I noticed that it can be either really subtle, or "son-of-a-b**ch" strong.

Now with LW's motion blur, what am I to do? does motion blur ... blur the alpha too? If I'm to render all of this stuff together it's going to take a whopping 18 minutes to render each frame...

What am I to do. Also my question still stands with the reflections... is it all or nothing?

Can you render the whole scene and have each object create it's own alpha channel? OR do I have to have to render out each item separately?

toby
03-06-2004, 03:12 PM
1. yes LW's motion blur does blur the alpha, I don't know about post - you might have to apply it manually but I'm sure it's not an issue, it would be uselsess if it didn't work with alphas.

2. generally you have to render things separately to get separate alphas or passes.

For example you could duplicate your scene, replace the geometry with nulls or set them to matte objects and render the HV by itself - HV generates an appropriate alpha channel.

In another scene, turn off all effects except for reflection and use the buffer export plug-in.

But if you need the HV to reflect in something, you'll have to render them together.

"Also my question still stands with the reflections... is it all or nothing?"

Everything that has reflection and everything that gets reflected needs to stay in the scene, everything else can go, and save that as a separate scene - the real speed advantage to this is indirect. It may take just as long to render, but you'll only have to do it once. Then you can blur it to taste, turn it up or down, etc. all in post.

Triple G
03-06-2004, 03:35 PM
Originally posted by toby
and Reel smart - the blur doesn't seem to go in the same direction as the movement

Try rendering each object on a separate layer and then applying ReelSmart. That sometimes helps.

Granted, it's not perfect, but its results are usually good enough where the speed increase over doing it in LW makes it worth it. That, and the fact that you have more flexibility because it's being done in post...you can even keyframe the amount of blur over time.

toby
03-06-2004, 04:18 PM
Originally posted by Triple G
Try rendering each object on a separate layer and then applying ReelSmart. That sometimes helps.

Granted, it's not perfect, but its results are usually good enough where the speed increase over doing it in LW makes it worth it. That, and the fact that you have more flexibility because it's being done in post...you can even keyframe the amount of blur over time.

hmm didn't change anything. I certainly like the flexibilty, it would be a nice plug-in to have around but I can't consider it a must-have

ArneK
03-06-2004, 06:07 PM
I know it doesn't help you right now, but the motion blur offered in Worley's new FPrime seems superior...

toby
03-06-2004, 08:01 PM
!!
yer right it looks awesome!