workflow from HD 59,94 P to DVD SD

logiquem wrote on 11/21/2009, 8:22 AM
Hi all,

I just begin serious work with my new GH1 footage...

I'm trying to figure how to have 720 P 59.94 footage rendered nicely for a standard DVD.

I'm after a fluid video look with best movement rendition, not cinematic look. This is a green screen project. What's the best workflow?

1. Project editing in DV 59,94 > footage croped in 4:3 > render in 720 30P (problem with "ghost" images).

2. Project editing in DV 59,94 > footage croped in 4:3 > render in 720 29.97i (fluid movement but terrible interlacing artefacts)

3. Project editing in HD 720 59,94P > crop > render in 720 30P (how do i do that?)

Thanks a lot,



logiquem wrote on 11/23/2009, 7:41 AM
Once more: anyone can comment on this or point me to a tutorial?

I'm trying in particular to get fluid looking 720P 60 footage on NTSC DVD and 29,97 i seems the only solution to extract the correct movement.

Do i have to make it in 2 steps to avoid interlaced artefacts :

1.downscale from 720 60P to 480 60P
2. render the 60P file to std 29,97i ?
kairosmatt wrote on 11/23/2009, 8:15 AM
Have you tried making a widescreen DVD 29.97i straight off the timeline? We did that with some 1080 60p work we did, and I don't remember seeing any interlacing artifacts.

The widescreen template will playback letterboxed on 4:3 TVs.

farss wrote on 11/23/2009, 12:40 PM
I've shot 720p50 to deliver a 50i DVD. On a 720p50 T/L render to SD 16:9 50i. Works a treat, almost, see below.

Rendering from 50/60p to 25/30p is going to be problematic. Two choices, drop every second frame or merge pairs of frames. The former will yield unsmooth motion, the later will give you bad looking blur with ghosts.

The problem with 720p50/60 is shutter speed. Assume a 180deg shutter. The amount of motion blur that creates at 50/60fps is half what you'd get at half the frame rate. This bit me to some extent even rendering to 50i.
My suggestion would be to edit on a 720p60 T/L and render to 60i. Take care if doing any panning or cropping that this is done to the progressive frames. I did this the wrong way around and I'm pretty certain some of my motion problems were due to field order reversal from the crop.

MPM wrote on 11/23/2009, 12:49 PM
**IF** you want to go through the trouble, there are a few scripts & tutorials for doing this with AviSynth, which you could use either as a feed to Vegas or with the Debugmode Frame Server, feed your timeline to AviSynth. What I've used follows Bob's 2nd model, where each frame is re-sized, then merged as fields in interlaced frames -- it's similar to what you can do in V/Dub splitting an interlaced frame into individual, editable fields, or put them back together. At any rate there are several filters, re-size methods etc., plus code/files to speed up the processing.