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Please help!! DVC pro 720p30 is acting STRANGE!
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[Herb Sevush] “How do you make the clips show 30 frames. Right now they show 60. “
Find the tc rate column in the browser, if you can’t see it, enable it and change from 60 to 30. And are you sure the clips are all 60 and don’t skip a frame (i.e. 2,4,6,8,10…60)? Tell me what the tc rate is showing, and I’ll tell you what you tc should be showing.
Jeremy
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[Jeremy Garchow] “Oh yeah? Why not? When talking about video, what does native get you? Why does editing in lossy DVCPro HD gain you anything at all? The point is not to lose anything further. “
If that’s what the point is, then you would want native capturing. But I fail to see your point. Do you consider “HD-SDI->DVCPro Re-encoding” a native capture?
[Jeremy Garchow] “So when Quicktime decodes it, it’s an exact duplicate?”
No, it’s not. But when you output via Firewire back to DVCProHD tape, it is.
Sean
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[Sean ONeil] “Do you consider “HD-SDI->DVCPro Re-encoding” a native capture? “
No. Never have. But I ask again, what does native get you?
[Sean ONeil] “No, it’s not. But when you output via Firewire back to DVCProHD tape, it is.”
OK. So you trust a Quicktime to decode an already lossy format, and not a hardware Kona card to do it in an uncompressed space?
Don’t get me wrong, DVCPro HD is an awesome in camera acquisition codec. It just doesn’t hold up to much editing/generation loss.
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[Jeremy Garchow] “No. Never have. But I ask again, what does native get you? “
It saves a generation. Instead of decoding it, re-encoding it, and then decoding it again, with native capture you are just decoding it once. There is no re-encoding.
[Jeremy Garchow] “OK. So you trust a Quicktime to decode an already lossy format, and not a hardware Kona card to do it in an uncompressed space? “
You’re taking old knowledge of the Apple software DV decoder and applying it to the Panasonic DVCProHD Quicktime component. They are not the same. DVCProHD is 4:2:2. Decoding it to 4:2:2 U/C is a trivial task for the decoder. It’s not the same as when software DV (4:1:1) decoding cause poor chroma up-sampling.
And I’m pretty sure that the Quicktime component (made by Panasonic, not Apple, I believe) uses the same algorithms as the SDI option board on Panasonic deck. I’m not even sure a Kona has it’s own decoder. AFAIK, it still uses the Quicktime component. It just provides hardware assistance to reduce the CPU load. In fact I’m quite sure that’s the case. Their sales language says “hardware accelerated” for DVCPro HD. If it had it’s own hardware codec, it would just say “hardware” without the “accelerated” part.
[Jeremy Garchow] “Don’t get me wrong, DVCPro HD is an awesome in camera acquisition codec. It just doesn’t hold up to much editing/generation loss. “
Well I agree with that, but I haven’t brought it up because it’s not the point I was making. Walter has time and again made a fervent argument that the generation loss is trivial. I had no desire to engage in that discussion. Saying it’s just as good as native is one thing. Saying it IS native is another. That’s what I had a problem with.
Sean
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[walter biscardi] “HD-SDI is definitely the way to go with DVCPro HD if you have HD-SDI out of your deck. “
you forgot to add there is not any audio offset when you import this way, with the FW capture the audio often needs to slew 2 frames to match the video.
gary adcock
Studio37
HD & Film Consultation
Post and Production Workflows
Inside look at the IoHD -
[Sean ONeil] “I didn’t want to engage in this discussion but this kind of false information just annoys the crap out of me. “
Sean
have you ever tested this?
I mean really tested this workflow on a scope? I did, in fact I am the guy that tested it for both companies (panasonic and aja) during the roll out of this feature.There is no more generational loss in this method than there is dubbing THAT video to any other format via BaseBand video.
—My tests at the time showed an average error of only a .5% ( 1/2 of 1 percent) difference that could be compensated for if very careful. When the original camera version captured via FW was overlaid with the “baseband converted copy” in “difference mode” The output of the combined file was then viewed on a Leader 5700 scope to highlight the issues.
That being said, I am “now” only a fan of camera codecs ( DVCPROHD, SxS, RED), for capture, at which they excel at. However after working in ProRes I will never go back to editing camera native content again.
gary adcock
Studio37
HD & Film Consultation
Post and Production Workflows
Inside look at the IoHD -
Gary –
“after working in ProRes I will never go back to editing camera native content again. “
Doesn’t capturing with ProRes involve creating much larger files. What are the advantages as you see it.
Also, what would be your workflow using ProRes when camera masters were DVCPRO HD and you had to deliver DVCPRO HD show masters.
Herb Sevush
Zebra Productions -
Well, I am no Gary Adcock, but I always take my edits out of DVCPro HD for finishing even if going back to DVCPro HD.
DId you get the 30 vs 60 sorted?
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[Jeremy Garchow] “Well, I am no Gary Adcock, but I always take my edits out of DVCPro HD for finishing even if going back to DVCPro HD.”
Now this I would not recommend as you definitely do take a quality hit when you go back to the DVCPro HD deck. If you’re going back to DVCPro HD, I would stay in that format all the way around.
It’s not a huge hit, but it is noticeable on our HDTV plasma screens as just a bit more noise, especially in the blue and dark areas of the screen. The home viewer would never know the difference, but the editor can notice it in certain scenes.
Walter Biscardi, Jr.
Biscardi Creative Media
HD and SD Production for Broadcast and Independent Productions.STOP STARING AND START GRADING WITH APPLE COLOR Apple Color Training DVD available now!
Read my Blog!
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[gary adcock] “My tests at the time showed an average error of only a .5% ( 1/2 of 1 percent) difference that could be compensated for if very careful. When the original camera version captured via FW was overlaid with the “baseband converted copy” in “difference mode” The output of the combined file was then viewed on a Leader 5700 scope to highlight the issues. “
You’ve completely missed my point. I’m not arguing the validity of the workflow. I’m not saying it creates any noticeable loss.
My sole point was that it is NOT native. That’s all. You’re own test, showing a .5% difference proves it. Do I think .5% is a big deal? No.
[gary adcock] “That being said, I am “now” only a fan of camera codecs ( DVCPROHD, SxS, RED), for capture, at which they excel at. However after working in ProRes I will never go back to editing camera native content again. “
ProRes is the only codec I’ve ever used since FCS2 came out.
Sean
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