24p jitter

vitalforce2 wrote on 4/8/2003, 1:17 PM

Okay. So the V4.0b update now gives me virgin 24p-in from my Panasonic DVX100, and I can edit and output my film without converting to or from the NTSC, 60i format. One result of this appears to be that in the edit mode, the Preview window now shows 24p motion, which to my eye is choppy when a subject is in motion (even after pre-rendering a segment). Should I address this now, with a little motion blur perhaps, or might I just edit in NTSC 60i, to play back more smoothly and thus better examine motion & timing, etc. By doing the latter, one wonders whether the 'jitter' will show up again on outputting to tape or DVD. (Or conversion to film.)

Question two: If the above can't be avoided, I wonder if there is a way to set the output for 48p, which is what film projectors actually show an audience--showing each 24p frame twice....

Comments

SonyDennis wrote on 4/9/2003, 1:31 PM

The External Monitor output always uses 2-3-3-2 pulldown, so it will have slightly more judder than a final 2-3 pulldown render. Try doing a 2-3 pulldown render or print to tape and then watch the output to see if it is to your liking. Obviously, 24p will always appear choppier than 60i, that's because it's only 40% as many frames per second.

You can output to 48p, but only to a format that supports it (such as AVI uncompressed, but not DV <g>).

///d@

john-beale wrote on 4/9/2003, 2:40 PM

As far as I know, there is no computer or video display device that would actually show you 48 frames per second as such. You can set your output rate to whatever you want, but the picture is actually refreshed on the screen at the rate of the video scan. If you set 48 from 24p input, you just double every frame, but I don't think the output changes visually. Updating the video frame buffer doesn't produce a flicker like the physical blade of a film projector does.

vitalforce2 wrote on 4/9/2003, 5:49 PM

Thanks for the advice, SonicDennis (and jbeale), and huzzah to SoFo for this remarkable upgrade. I feel like I'm riding an historic wave of creativity with this union of V4 and the DVX100. --Or maybe it's just I drank too much coffee...Well, whatever works. :^)

JJKizak wrote on 4/9/2003, 6:49 PM

I'm trying to get rid of the judder on my tapes(converted films) and you
guys are trying to put it back in. You can't please everybody.

JJK

tvdias wrote on 4/9/2003, 8:10 PM

"As far as I know, there is no computer or video display device that would actually show you 48 frames per second as such"

Sure, there is. Any multiscanning front projection CRT device can do this. I have actually used 48P on my NEC 751 projector. It eliminates the need for 3-2 pulldown processing.

Vern Dias