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dranos
10-25-2006, 12:26 PM
Hi all,

Can LW's field render option. I found that rendering with 'lower' fields and then importing the animation into Final Cut for playback produces super smooth movement. When using After Effects to create animation, I also find that 'lower' fields produces the smoothest playback.
The problem is that when I render animations from LW with 'lower' fields then add it to other animations done in After Effects and output from AE using 'lower' fields, somehow the LW sections come out choppyt when played back in Final Cut.
I tried rendering from LW in 'upper' fields compositing it with animations in AE, then outputing everything in 'lower' fields, playback in Final Cut and everything plays smooth.
Whats up with that? When should I use upper field or lower fields?

Thanks in advance.

Sekhar
10-25-2006, 01:53 PM
Are you sure that AE is interpreting your LW render field order correctly? You can check this with interpret footage (Ctrl-F).

eblu
10-25-2006, 02:30 PM
are you moving the footage vertically? scaling it?
are you rendering in a different size (such as rendering in 640 x 480, and compositing in 720 x 480?)

dranos
10-25-2006, 02:48 PM
Are you sure that AE is interpreting your LW render field order correctly? You can check this with interpret footage (Ctrl-F).

Thanks,
That seems to have solved the issue. I've never used the 'fields' option in the 'interpret footage' window before. Once I selected the correct type it rendered fine.
Its kind of wierd though how prior to doing this, AE somehow took the upper fields animation from LW then rendered it smooth only if I chose lower fields in the render settings.

Is there a rule in using fields when rendering?

dsol
10-26-2006, 06:38 AM
Is there a rule in using fields when rendering?

I don't know if it's different for NTSC, but online PAL video is typically handled upper-field first (Avids and FCP online suites). DV is usually lower-field first. It's easy to change field order though if there's any problems. You can either interpret the footage differently, or knock off a vertical line and shift the image up or down a pixel.

dsol
10-26-2006, 06:40 AM
The super-smooth look of interlaced video is generally disliked by most of my clients though. It looks like "Video" as opposed to "Film". Good quality motion blur is important if you're not rendering with fields though

dranos
10-26-2006, 07:22 AM
The super-smooth look of interlaced video is generally disliked by most of my clients though. It looks like "Video" as opposed to "Film". Good quality motion blur is important if you're not rendering with fields though

That's interesting. I would think they would love it since it makes everything more legible. When doing crawls it's a definate must that I use fields, or else you eyes wont be able to follow the text easily. Whats is a 'good quality motion blur' generally speaking?

dsol
10-26-2006, 07:41 AM
Whats is a 'good quality motion blur' generally speaking?

Mmmm... well, LW's current motion blur isn't too great. Vector Blur seems to give smoother looking end results, though it can cause render artifacts occasionally (plus you need to render with oversize borders - it messes up the edges). FPrime has nice MB from what i've seen, and the next release of LW also tackles the MB issues well.

I guess what I was trying to say was that if you don't render using fields, then using motion blur is essential - and that the resulting motion blur needs to be clean-looking (and as un-stepped) as possible as the lower temporal rate means the eye can percieve individual frames more easily. I personally consider Enhanced Medium AA (or the equivalent number of passes using PLC) to be the minimum I can get away with on fast motion graphics.

dranos
10-26-2006, 08:00 AM
Mmmm... well, LW's current motion blur isn't too great. Vector Blur seems to give smoother looking end results, though it can cause render artifacts occasionally (plus you need to render with oversize borders - it messes up the edges). FPrime has nice MB from what i've seen, and the next release of LW also tackles the MB issues well.

I guess what I was trying to say was that if you don't render using fields, then using motion blur is essential - and that the resulting motion blur needs to be clean-looking (and as un-stepped) as possible as the lower temporal rate means the eye can percieve individual frames more easily. I personally consider Enhanced Medium AA (or the equivalent number of passes using PLC) to be the minimum I can get away with on fast motion graphics.

Thanks for the info. I'll try and apply this to future projects.

Sekhar
10-26-2006, 08:09 AM
Dranos, whether you use interlaced or progressive depends on what footage you're compositing/mixing with and what your end goal is.

If your other footage in AE (either captured through camera or rendered through AE, etc.) is interlaced, you want to keep the LW also interlaced, with the same field order. And if it's progressive, keep your LW render also progressive. Interlaced and progressive have different looks and you don't want to mix them up.

You're right, the net result with progressive/blur will not be as legible as interlaced. But the main attraction of progressive is to give a film-like appearance, since motion picture is 24 fps progressive (24p) and people associate 24p with storytelling. So, if your goal is tell a story, 24p is the way to go.

But if you're trying to communicate information (like say for an industrial video), interlaced could be a better choice since everthing appears legibly. It may not have the dreamy film-look, but it would convey the information.

avkills
10-29-2006, 06:00 PM
You can render 60fps progressive in LW and have AE interpret it as that, and then it will look even better than rendering 30fps interlaced. Although the time hit is tough to swallow.

-mark

dranos
10-29-2006, 06:09 PM
This is all very interesting, thanks. Stupid question, where in LW do I find the option to render progressive? I'm really not a film buff. I learnt all I know from reading and participating in these forums.

Sekhar
10-29-2006, 07:03 PM
Progressive is the default - basically one full frame after another.