Progressive VS Interlaced?

[Alexxx]

Hi Adam,
Although coming from PAL-land I cannot relate 100% to your problem in NTSC, but I believe the specifics still apply. Once you start scaling and moving interlaced footage you start to run into interlacing problems as you mix-up the even-odd line referencing inherited in the original frame. So generally in cases where scaling and movement of interlaced footage is required, a de-interlace is needed first.

I would suggest shooting progressive as you retain the full frame resolution, key off that, do all the scaling and motion and then do pull-down and interlace.

Cheers

Alex

http://www.lightdrop.com.au

[Tony Kloiber]

If you have the option shoot a 30p. Work in your 720X540 NTSC comp and render. Even if you shot 24p the length of each shot in a commercial spot is so small you probably won’t have to sweat the milliseconds.

Partly it depends on the look you want, do it all at 24p and it will have that feel, do it all at 30f and it will have that feel. I’d agree with Alex that your biggest problem might be interlace artifacting when scaling and moving an element, but if your using HD in a SD comp those problems (if they happen) will be much smaller because you’ll be scaling down the element so much.

Shooting in a full (or non-compressed) color space would be the other thing to look out for. HDV is not HD it is better then DV for keying when you scale it down but it is still without color.

TonyTony

[David Bogie]

I have no help to offer, just an observation because these these frame rate and interlacing questions always puzzle me.

I’ve been shooting standard NTSC for almost four decades. I’ve been using nonlinear since Media 100 v2 and AE since it was CoSA and I’ve rarely had any trouble with interlacing on anything I’ve ever done.

The problems I have with interlacing are almost always caused by someone else’s footage or improperly rendered effects handed to me.

bogiesan

This is my standard sigfile so do not take it personally: “For crying out loud, read the freakin’ manual.”

[Adam Duguay]

Hi Tony! and thanks to everyone for your responses.

Tony, what did you mean by

(Shooting in a full (or non-compressed) color space would be the other thing to look out for. HDV is not HD it is better then DV for keying when you scale it down but it is still without color.)

Can you elaborate on this a little more? I think what we’re going to do is shoot 24p. Now let me ask you a question about workflow in After Effects. When I get my footage digitized I’ll have it exported as 1920X1080 24P. I’ll bring those files into After Effects and do all of the keying as pre-comps. Then when I’m ready to start incorporating that into my final scene, what should I work at? 720X 540? If the frame rate of the footage is different from the working comp will this cause problems in the final render? Should I be doing a pull down on the Keyed footage to 59.94 and then adding the pull down HD keyed footage to my 29.97 720X540 comp?

Sorry if this sound convoluted.

Hope someone can help.

Adam

[Tony Kloiber]

I think Dave covered it.

TonyTony

[Adam Duguay]

Dave,

You rock man! thanks so much, very clear. I totally get it now.

So here’s a little tid bit of information I received today. I found out that it is confirmed that we are using a new HDX 900 Panasonic HD Cam. Do you have any experience in working with footage from this camera? Apparently the camera man has told me that the Panasonic line of HD cameras processes the progressive frames a little differently then the Sony cameras do. I’m hoping that the camera man will be able to shoot 1920X1080 24p. Then I’ll have an Avid Nitris digitize the frames at the native format and export them to me.

Thoughts?

A