60i Footage

M

mikepl

Member
I shot 60i (dv) footage and imported at 29.97 into Premiere pro. I then brought the footage into After Effects on a 23.98 timeline. After I interpret the footage with lower field I still notice interlacing ( The shot is of a building so you can see the jagged lines )

As some might be able to tell I am going to make the clip slow motion. But until I can clean up the interlacing i can't use the chip.

Thanks for the help.
 
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1) Simply drop into the composition, don't have to use a 24 fps timeline.
2) Interpret as lower field first
3) Go into Effect, Time Stretch and stretch by 200%.
4) Render out, and ta-da, you have 60p.
 
What is the final destination of the video going to be? Iv if it for anything other than the web, it's for TV, DVD, ect, Don't wory about interpreting the footage lower field. Turn that option off.

Most of what you are going to watch is going to be interlaced anyway, and the best quality you get out of AE for footage that will be interlaced is upon rendering, set it to render fields. Unless you are doing some serious tweakge, you don't need the Lower Field first interperetation, and in fact, you lose a little bit of quality going that route.

Also, enable frame blending and give that a shot. It may help.
 
Its kind of weird.

If I use lower fields then building's lines are extremely interlaced but if I turn off fields or use upper field then my subject walking is extremely ( lower portion of the screen ) interlaced. I cant seem to win.
 
The problem with using the Upper of Lower field interpolation is AE tries to recreate non-interlaced frames, and the result can be as you have seen, graphical anomalies. The worst offenders are things like power lines, where when left at no interpolation they look great, but with lower field, even with preserve edges, you can get jaggies.

But since you are going to have it in a 24p timeline, you are going to have to bite the bulled and do what jade8472 suggested.

Or, there is another route, something Barry Green has gone over in his book. It is not slow motion down to 50%, but something more like 80% speed. Since you are shooting (effectively) at 29.97 and have a workspace of 24, you have 6 frames per second that you won't use in the 24p timeline. But using those frames as is, your footage is naturally slowed down buy the equivalent of 6 frames per second, or 4/5ths of the overall playback.

But with 24p, you have to get rid of those jaggies. Try this:

Open the footage you wish to slow down in AE and bring it into its own comp.

Then open another instance of that footage. Tell one file to be treated as Upper field first with Preserve Edges, and the other as Lower field with Preserve edges. Put the Upper field clip above the lower field clip in your comp and reduce the opacity of the Upper field clip to 50%. You will get a softening effect a little, but many of the Interpret footage artifacts will simply disappear, and even better, since you will be using the final output in a 24p setup which has a shutter speed of 1/48th, by using the Upper and Lower field technique, you fake the look of a shutter speed of 1/40th of a second, which will blend in much better with your original footage.

It won't look as crisp as the 24p stuff, but the motion blur will help, and you can always do a tad of Unsharp Mask to get it to fit.

Then, you import you final output from AE into you NLE and set its playback to I think 80% I've never done it, but a little research will get you through. I believe the reason you tell it to play back at 80% is so your NLE will not try and squash it into and 24p timeline, and you will get all of your frames that way. It's not that slow, but is as he says "The cleanest you will get out of a video camera". Makes sense, since the 6 extra fames you have coming from 29.97 are 20% of the 24 in 24p, and hence the clean slowdown when you set your 29.97 footage to 80%.

There are, many topics about this in the Vegas section, so you may find some answers there.

Plus there is always the option of using Timewarp in AE or the Retimer plugin.
 
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