DVD Studio Pro Disc Strobing on TVS... I don't think it's field dominance.

Mankin

Member
Hi all,

I don't post too often, as I find that searches usually take care of my basic needs. Thanks for providing such a rich resource of information. Now on to the problem...

I've been working on a project that was shot on my DVX100b at 24p (not advanced). I have shot other projects with this setting that have output to dvd just fine, so I don't think it is the 24p is making it strobe.

In the camera's viewfinder and screen, the footage is fine. There is no strobe or artifacts, it's fine. When I play the footage in FCP, it is also fine. I have laid some effects filter from misfire over the stuff. But still in FCP, it looks fine.

So using compressor, I exported the footage to MP2 format using the Best Quality 90 minutes 4:3 filter. I checked field dominance, and all is set to lower field first.

When I play the footage on a tv on a standalone player it gets this jittery stroby look, like you might expect from a field dominance issue. I havetried the disc on a set top dvd player with a tube television, and my 360 and PS3 on my HDTV, all look the same, although the PS3 handles it a *little* better. I have also played the DVD on the DVD utility on my Mac, and had NO problem with the footage. (which is why it seems like field dominance to me, but if all the settings are set to lower, how can this be?)

I tried a better type of disc media too, fearing it was maxell's crappy quality media, but the sony DVD-R's did this as well.

At any rate, when I used frame advance on the PS3 I noticed something. It's only on moving objects, and it seemas like objects in motion (just the area in motion) jump back a frae every 2 frames. After seeing this I tested the disc using frame advance on the Mac's DVD player utility... the frames did NOT jump back but played smooth. The other 24p project that looked fine passed this test on both the TV and the Mac...

Just kinda weird and I really need to figure out what's going on... Is compressor hit and miss on it's encodes? Is it the red giant filters (the project that worked fine used no filters), is it DVD studio pro.... any help would be appreciated.
 
You shot it in progressive, and compressor will normally detect footage as such and report accordingly in the summary on the first tab. Maybe check your FCP timeline. It should be a NTSC timeline as that's what 24p edits in. (24PA imports into a 24fps timeline.) The bottom line is there should be no field dominance as there aren't two fields.
 
Thank you for the speedy reply. I will try that and report back.

Oe quick question though. If I shot a wedding ad used the exact same workflow, why did it come out ok ad this project didn't? That's what is the most mind boggling thing about this.
 
Thank you. It stopped the strobing, but when viewed on an HDTV, I'm getting slightly more interlacing now than I think I should. I was wandering if there was a way to avoid this now? Sorry to ask so many questions, but you seem to know what you're talking about. Thank you Ming.

For the record, after I took your advice, I changed my FCP setting to no field dominance, but it was already in NTSC 29.97, which is correct for 24P, correct?

Mankin
 
Ok, so I did some mroe tests last night. I went back to moving the timeline to bottom field dominance and exported mpeg2 from compressor with bottom field doinance as well. But this time I exported two different versions. One had all of my Look Suite and Misfire Effects on it (was just trying to see if I got a bad encode), and the other one, I took all of the effects off, and just exported untouched video with the exact same settings as the timeline with the effects added. The one with the effects added still had the previous strobing issue, but the one with out the effects looked crystal clear with no problems at all.

So it appears that magic bullet is that problem. But why? and how can I fix this? Any clues at all?

Mankin
 
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