Field Order Driving Me Crazy

[bingjoe]

Hi,

I have just completed an animation and am rendering to DVD (PAL). All documentation on the Internet says DVD PAL is interlaced and field order is lower field first. I have also sen other documentation refer to odd and even fields, with odd being top and even being lower.

However, field rendering option in Lightwave appears to contradict this and says even is upper first while odd is lower first !!

What's going on - any ideas ?

Thanks,

Joe

P.S. With field rendering option on, will I see any difference in the individual frames ?

[wrench]

Standards, eh? Doncha love 'em? The field names in LightWave have been changed several times to meet the fashion of the day, and the answer is always to suck it and see because you can be sure that whichever you choose it'll be the wrong one. :( If you have any motion in your scene you will see field rendering quite clearly as a kind of zipper effect across your images. Depending on what you are doing, it may even not be worth going to field rendering at all, and just rendering normally.

B

[bingjoe]

Thanks.

Why am I not surprised ?

Joe

[SBowie]

I've never found "odd" and "even" to be of any use in this context. Some manufacturers and developers refer to the upper field as 0 (even), while many others tag it "1" (odd). It's best, imho, to refer exclusively to "upper" and "lower".

[bingjoe]

Well, I took 'wrenchs' advice and tried a number of permutations and combinations. I had 25 fps no fields, then upper first, then lower first and rendered all to DVD.

"No fields" was still a bit jerky (mmm), "upper fields first" were very jerky (as expected), but "lower field first" was about the same as no fields ie. still a bit jerky !! I did expect this to be the best of the lot (if not perfect).

Now I am confused. This is a simple animation, with a simple object traversing the screen ( so a linear motion along the X axis ). DVD PAL is (25 fps I understand) so at the moment, I am at a complete loss !!!

I have Motion Blur on too.

Any further ideas appreciated ?

Cheers,

Joe

[bingjoe]

:thumbsup:

Got it !

The missing piece seemed to be some initial Premiere project settings. Re-ran the tests, and now results were as expected. Lower fields first smooth, other options jerky. Am happily re-rendering my project at 25 fps as I speak.

Thanks wrench & SBowie.

Cheers,

Joe

[wrench]

Hurray!

B

[ridasaleeb2]

Ah, but wait 'till you try lens flares- you're not there yet?:hammer:

[The Dommo]

PAL DV is lower field first (odd), PAL broadcast & various codecs to do with that are Upper field first (even).

However for DVD, it can actually be either.
So long as your MPEG2 encoder knows which order to put the fields in which must match the source material, then the DVD player will read the 'flag' in the video stream and deal with it correctly.

I ran a Matrox suite for a few years, and they made DV upper field first to be in line with broadcast. So because of this, we naturally did all our DVD video and menus as upper field first, opposite of Premiere's native settings of lower field first.

As I say, so long as the encoding matches the source, then you will be fine and silky smooth. I'm quite a fan of interlaced footage for that smoothness. :)