Update on 60i conversion to 24p

[Graeme Nattress]

If you have plugin issues, you should also email me direct. I try to read ALL the forums, but….

It really sounds like you’re mixing things up. If you’re using Film Effects, stay on a 29.97fps timeline. If you’re using Standards Converter, go with the 23.98fps timeline, but as far as I know, iDVD doesn’t do 24p DVDs properly. Even with DVDSP, you should use compressor for making the MPEGs from the 24p converted material.

Graeme

– http://www.nattress.com – Film Effects and Standards Conversion for FCP

[David Uloth]

Ah, Mr. Nattress!

I didn’t even think to email you. I’m so programmed to head straight for Creative Cow whenever I’ve got a question…

I am using Film Effects for the colour-correction effects and had tried Standards Conversion for the 60i to 24p conversion. So they were both applied to the clips.

I’ve tried keeping the clips in a 29.97 timeline and using Film Effects’ NTSC to 24p plugin (2 fields with 100% motion blur, 100% anti-aliasing, and 100% tolerance). When I exported a 29.97 quicktime file of this rendered sequence and burned it to DVD with iDVD, the motion jerks. There’s no real artifacts or anything like that in the image, it just jerks, as if it were a key-frame or conversion problem. When I go frame-by-frame on the DVD I can see that each frame is whole and not interlaced, and that there are 6 duplicated frames per second.

So I tried putting the clips on a 23.08 timeline and using Standards Conversions’ plugin to go from 60i to 24p (using 2 fields, 100% motion blur, 100% anti-aliasing and 100% tolerance). Plus I added Film Effects colour correction plugins to the clips. The movement of the rendered clips in the timeline is very smooth but I can see horizontal breaks whenever there is too much movement in the image.

These horizontal breaks are very evident in the 29.97 exported quicktime file of the sequence that I burned to DVD with iDVD. Like I said in my last post, if the horizontal breaks could somehow be eliminated, then the conversion would be excellent because it is very smooth and film-like.

I’m not a pro with DVDSP, and I knew that iDVD had problems with 24p, that’s why I exported each 24p rendered sequence at 29.97 fps before I burned the DVDs…but I have no idea whether that has helped or not.

In any case, I finally tried using Film Effects to go from 60i to 30p and that worked fine. Not jerks and no horizontal artifacts. But the motion is predictably DV-like, not very film-like.

Would going from 60i to 30P and then from 30p to 24p make a difference? Or how about if I exported the 24p clips as 24p quicktime files? (But then I would run into iDVD compression problems, I guess, when I try to burn a 24p DVD)

Thanks for you help!

Independent Producer/Director
Sure Shot Productions
Montreal, Quebec, Canada

[Graeme Nattress]

I wonder if iDVD guessed the field order wrong or something. That would account for jerking. I’ve certainly seen DVD programs guess it wrong.

For the 60i to 24p, with horizontals, sounds like an incorrect setting on the smart de-interlace. That’d be my best guess.

If you want a 24p into iDVD then yes, you must make it back to 29.97fps, but that’s done by adding 3:2 pulldown, which FCP won’t do if you put 24p on a 60i timeline. My plugins will, but at that point, you’ll get exactly the same effect as if you’d use Film Effects.

Drop me an email and I can give you a call later today,

Graeme

– http://www.nattress.com – Film Effects and Standards Conversion for FCP