HD rendering at 60Fps.

[Hemanth Kumar]

You will have to reinterpret the footage frame rate to

48fps=1080p24
50fps=1080p25
60fps=1080p30
48fps=1080i48
50fps=1080i50
59.94llllyfps=1080i59.94
60fps=720p30
59.97=720p59.94
60fps=720p60

this is based on the compsettings you use

after effects will automatically field your source

regards
Hemanth

[Steve Roberts]

Umm … not quite.

For 29.97 interlaced, take the 60 fps material, interpret it as 59.94 and drag it into a 59.94 comp. Render as 29.97 with fields.

However, if you change the frame rate of 60 fps material in the interpretation dialog to 48 or 50, you’re just making it play longer and slightly slower. If you don’t want to change the speed, for 48 or 50 fps, you need something like the Twixtor plugin to actually create new frames in-between the existing.

Does that help?

[Pascal Desfoux]

Dear Steve,
Thanks a lot for your prompt reply.

So for original render @ 60Fps (no fields),the right workflow for NTSC is :
– Import .tga seq. 60Fps (no fields) in AE
– Go to interpret footage & set interpret @ 59,94Fps.
– Open a new comp. with settings 1920×1080 @ 59,94Fps.
– Go to render with settings 1920×1080 @ 29,97Fps. with fields

& for PAL it should be :
– Import .tga seq. 60Fps (no fields) in AE
– Go to interpret footage & set interpret @ 50Fps.(say 50, no Twixtor, OK?)
– Open a new comp. with settings 1920×1080 @ 50Fps.
– Go to render with settings 1920×1080 @ 25Fps. with fields

In the PAL case the animation will render a little bit slower, of course.

Do you confirm my interpretation of your answer ?
Do you confirm it’s better to render original material @ twice frame rate to obtain with this workflow the best HD interlaced image ?
Do you confirm that with this workflow (double frame rate) any interlaced image is formed of two FULL field, giving a better result ?

Thanks in advance Steve for your attention & have a nice H-day !
Pascal

[Steve Roberts]

Yes on all counts. 🙂

(since you realize that the 50 animation will run a bit slower, it’s OK then)

3D material is often rendered at twice the final frame rate. It’s quite normal.

Now, if you want to compare quality between:
a) rendering to fields at 29.97 within the 3D application
b) rendering to 60 fps in the 3D app then converting to fields in AE …
.. I have no opinion. The quality should be identical, but I haven’t tested. Anyway, I’d never render to fields in a 3D app, as it might limit my flexibility later on. I’d pick (b).

Hope that helps,
Steve

[Pascal Desfoux]

Yes Steve it helps me a lot.

I’d pick (B) too. I suppose that in this case any final interladed image should be formed by two FULL fields, reducing in this way unwanted aliasing artifacts. What do you think ?
Thanks
Pascal

[Steve Roberts]

Well … it’s my understanding that any app that creates interlaced renders does so by rendering the odd fields, moving forward 1/60 (or 1/50) of a second, then rendering the even fields, combining them together into one frame, then moving on.

AE would take the first frame of a 60 fps render and delete the even lines, then move ahead to the next frame and delete the odd lines, then combine them, and so on.

So I don’t think there’s a difference between using the 3D app to render 30 fps interlaced, and using it to render 60 full frames(then interlacing in AE).

At least that’s my understanding of it.

Does that help?
Steve