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Realimagesvideo
10-07-2006, 08:05 PM
I should know this but I have not rendered for video (ntsc) for a long time so I forgot. What's the field order for video ntsc? Is it odd first? I am using lightwave 9. I've been looking through the manual and haven't found the answer there or searching the forum.

Thanks!

Sekhar
10-07-2006, 08:42 PM
There is no one order, it depends on the equipment. Use the same order as your footage, and you'll be fine.

JamesCurtis
10-07-2006, 10:03 PM
I think that is what he's trying to determine.

If you're not sure, try a smal video sequence both ways. You'll definately be able to tell which is correct

RedBull
10-07-2006, 11:04 PM
PAL: 50 fields per second, 625 lines, odd field drawn first (Upper)
SECAM: 50 fields per second, 625 lines
NTSC: 59.94 fields per second, 525 lines, even field drawn first (Lower)

This is assuming you are using Analogue of course.

DV standards are different. (for PAL)
PAL footage from DV sources are Lower or Even fields first.
NTSC is also Lower or Even fields first. (or the same as analogue)

Realimagesvideo
10-08-2006, 01:00 PM
RedBull

Your post is confusing to me. Lightwave field rendering options are:

"Even/Upper First"
"Odd/Lower First"

I'm rendering to NTSC (USA).

Sekhar
10-08-2006, 01:21 PM
William, there is no one order - you render to upper or lower field depending on the field order of the footage with which you're going to use the LW render.

E.g., some cards capturing DV footage will generate lower field video; others, upper field. If you're also using video from other sources (e.g., output of After Effects), again it depends on how it was rendered - could be upper field or lower field.

So, if your footage with which you're going to use your LW render is upper field, then render out to upper field; if it's lower field, render out to lower field. It's impossible to come up with an answer unless we know what your destination is.

Some apps will help you determine the field order. E.g., if you're using Premiere Pro render in After Effects, AE will automatically determine the field order that PPro used, so you're in luck. In other cases, you'll have to guess.

The field ordering thing is a pesky issue, but there are many resources on the net to help you out. If you have AE, check the manual - they explain quite well.

UnCommonGrafx
10-08-2006, 02:36 PM
Hey William,
I put this here to make sure I could find it when this question came up again, as it invariably does:
http://forums.creativecow.net/cgi-bin/new_read_post.cgi?forumid=123&postid=854885

toby
10-08-2006, 05:34 PM
Hey William,
I put this here to make sure I could find it when this question came up again, as it invariably does:
http://forums.creativecow.net/cgi-bin/new_read_post.cgi?forumid=123&postid=854885
NATURALLY the answer adds more confusion! :confused: :bangwall:
One thing I noticed while wrestling with this issue, After Effects can tell you what your footage is when you import it -

I don't think you have to render to fields anyway, do you? Digital Domain never does, so I don't... it takes a lot longer to render, and it can be interlaced afterwards, in something like AE. I did some tests by putting the video on dvd and found that I needed to render Lower field first, at 720x480 out of After effects.

UnCommonGrafx
10-08-2006, 05:42 PM
But there is a LOOK you can get with it being rendered (edit is here) that you can't necessarily get with a doubling of the frames. Heavy motion comes to mind.

Having said that, if they ever release the cool motion blur that Granger showed this will be a moot point.

Nonetheless, time is money and faster is more money. To that end, Toby, you have a good point. ;)

Sekhar
10-08-2006, 05:43 PM
NATURALLY the answer adds more confusion! :confused: :bangwall:
One thing I noticed while wrestling with this issue, After Effects can tell you what your footage is when you import it -

I don't think you have to render to fields anyway, do you? Digital Domain never does, so I don't... it takes a lot longer to render, and it can be interlaced afterwards, in something like AE. I did some tests by putting the video on dvd and found that I needed to render Lower field first, at 720x480 out of After effects.
AE only detects correctly when reading some files, e.g. those generated by PPro (apparently, PPro adds that info in the file). I've seen AE make the wrong detection and had to manually re-interpret the footage.

If you're mixing the LW output with interlaced footage, it's better to interlace in LW because the look is different - you'll be able to tell the LW section apart. AE can convert it to interlaced, but it won't be as accurate as doing it in LW if there is a lot of motion.

toby
10-08-2006, 05:54 PM
Nice to hear from experienced people on this :D
That 's what I've always wondered about DD, even the top VFX supervisor, with the stuff that they're trying to win awards with, nothing gets rendered with fields, or at 60fps for accurate conversion. Very frequently it's rendered at 24 fps! So my guess is that they're aiming at a less-video, more-film look?

Sekhar
10-08-2006, 06:08 PM
24p is pretty much the standard these days in video (the craze really caught on with the Panasonic DVX100), and you'll be hard pressed to find anyone delivering in interlaced. Even folks shooting interlaced with older DV cams invariably de-interlace with tools like Magic Bullet to 24p (I do, anyway) to get that elusive film look. If we're inserting the LW anim into this kind of 24p footage, you're right, the whole interlaced thing is moot.

toby
10-08-2006, 08:07 PM
And in a few years interlacing will be gone anyway, right? Please, God?!