Interlaced vs. Deinterlaced

[Steve Roberts]

You must separate footage (check the help) when moving, rotating, scaling or otherwise distorting footage in AE. If you’re not doing that, you don’t have to separate fields. Unless your final video will show on a computer. The you should separate fields and render “no fields”, because interlacing looks bad on a computer.

Most of us here don’t like the interlaced look anyway, so we separate.

Interlacing is an historical way of creating smoother-looking footage.

For more info, check the help or Google “after effects” and “interlaced”.

[Kevin Camp]

if you are just color correcting you wouldn’t need to deinterlace… but if you wer going to manipulate the scale or vertical postion of the footage, or use effects for keying, bluring or most other effects, you should deinterlace… its easy, ae often does it automaticly, but you can check by selecting the footage in the project window, choose file>interpret footage>main and then choose separtate fields (with the correct order). that’s it.

now to render with fields back in, send the comp tothe render queue, click the render settings and choose field render with the correct dominance.

Kevin Camp
Designer – KCPQ, KMYQ & KRCW

[Darby Edelen]

You should de-interlace your footage for compositing and effects. If it will be displayed on an interlaced device you will want interlacing in the final footage (it can be added in when rendered). Note that DVD players can take 23.976fps progressive footage and display it properly on a 29.97fps interlaced NTSC device (for us North American folk).

Darby Edelen
DVD Menu Artist
Left Coast Digital
Aptos, CA

[Steve Roberts]

[Darby Edelen] “If it will be displayed on an interlaced device you will want interlacing in the final footage (it can be added in when rendered)”

That’s an aesthetic choice, not a requirement.

An interlaced device displays progressive footage as two identical interlaced fields, so it can handle progressive.

However, if you choose to render as interlaced, you must choose the proper field order. DV is lower field first. Old Media 100s are upper field first. New Media 100s are lower field first. There are many other options, depending on your output hardware or your editor’s hardware. … if that appies to your situation, of course.

[Darby Edelen]

[Steve Roberts] “That’s an aesthetic choice, not a requirement.”

It’s true! It’s true… I’m just trying to lead more people to my camp =)

To expand on my thoughts, if your footage will be potentially displayed on progressive & interlaced you should definitely go with progressive. If you know it’s going to be on an interlaced device (which is over 99% of all TVs in the world) I prefer to render with interlaced fields as I find it helps capture motion better.

Darby Edelen
DVD Menu Artist
Left Coast Digital
Aptos, CA

[Mbevilacqua]

I have deinterlaced footage to add effects and composite with CG on a PAL/DV project.
Should I render fields (lower first) if outputting to DVCAM to be projected then?
In this work flow would progressive work too?

Thank you.

[Kevin Camp]

either should work fine… for me, that decision depends largely on the movement in the project. if there is a lot of movement (and the destination is interlaced) then i usually render fields, if the movement is more subtle, then i render progressive.

in your case, if the projection screen is on the large side and people may be close to it, and the movement isn’t too fast, you might want to render progressive, since the enlarged scan lines will be more appearent and possibly distracting. but you could always try both if you have the time.

Kevin Camp
Designer – KCPQ, KMYQ & KRCW