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Please help!! DVC pro 720p30 is acting STRANGE!
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[Sean ONeil] “Why do you prefer HD-SDI over firewire? You are aware that by using HD-SDI, you cannot capture natively?”
With the AJA Kona boards, they are actually coming in native via HD-SDI. I’ve had many discussions with the tech gurus at AJA and when you come in via HD-SDI on a Kona board, you’re coming in native and actually it’s a bit cleaner thanks to some nice work AJA did tweaking the input.
HD-SDI is definitely the way to go with DVCPro HD if you have HD-SDI out of your deck. I used to do the Firewire workflow, but we switched about two years ago and that’s the only way I would recommend anyone work with this codec.
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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[Herb Sevush] “What doesn’t exist, surprisingly, is a blackmagic easy-setup for 720P30. They have one for 720P60 and 720P24 but nothing for 30.”
AJA doesn’t have a native one either, but we just made one. It works just fine to take the AJA Kona 3 DVCPro HD 720/59.94 Easy Setup and change it to 30. Works very nicely, though I’m not a fan of the 30p look
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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[walter biscardi] “With the AJA Kona boards, they are actually coming in native via HD-SDI. I’ve had many discussions with the tech gurus at AJA and when you come in via HD-SDI on a Kona board, you’re coming in native and actually it’s a bit cleaner thanks to some nice work AJA did tweaking the input. “
Walter, we’ve had this discussion before. If they told you that, they are lying. I mean, it’s almost like saying “A few reps from McDonald’s development team told me that Big Macs are are actually heathy for you.”
I have no problem with your workflow whatsoever. I do have a serious problem with false information being proclaimed by a Cow leader. HD-SDI capture is not native, and the definition of “native” is not in dispute.
This is how it works. An AJ-HD1400 w/ the HD-SDI option, for example, has an onboard decoder chip. On playback, it decodes the DVCProHD video to uncompressed video. The raster size is scaled from 970×720 to the standard 1280×720. This uncompressed video is serialized and fed to an HD-SDI transmitter chip. Anything plugged into that SDI port sees nothing more than a SMPTE compliant uncompressed serial digital video signal. It does not see anything having to do with the DVCProHD codec, or how to re-encode it losslessly. Nothing whatsoever.
Thus it is not native. It is a physical impossibility. Furthermore, if they “tweaked” the input to supposedly make it look better, that in and of itself proves it is not native. Additionally, it wouldn’t be the input that they tweaked, it would be the onboard encoder. If the input was tweaked it wouldn’t be SMTPE compliant. SDI is a pretty straightforward and the levels are not altered by the Kona or any other capture card.
Native means an exact 1:1 digital duplication of the data that is on the DVCPro tape. That’s what “native” means. Just as if you copied it from a P2 card or a hard drive. It doesn’t mean anything else. So if it looks better, then it isn’t native. Period. Just because it’s impossible to detect any differences visually or on a WFM, doesn’t make it native. The only way it can be called native is if the 1’s and 0’s on the tape are 100% identical to the Quicktime file you have captured.
If AJA claims it’s native, they risk being sued, because it isn’t. That’s why they don’t claim it – publicly at least. But don’t take my word for it. This is from the AJA website:
“The Panasonic DVCPROHD format takes advantage of KONA hardware as well. KONA’s precision hardware allows capture and playback of HD-SDI video to and from the DVCPROHD codec at a quality level virtually indistinguishable from native FireWire, while freeing up valuable RT processing power.”
Saying “virtually indistinguishable from native” explicitly means it is NOT native. Furthermore it does not say it looks better. How can it look better if it’s virtually indistinguishable?
It should also be noted that the topic creator is using Blackmagic hardware, not AJA.
Again, I’m well aware AJA thinks you should use their products for every workflow. No shit they think that. They have families to feed. I didn’t want to engage in this discussion but this kind of false information just annoys the crap out of me.
Sean
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[Herb Sevush] “I am aware of the none native nature of HD-SDI capture. I have had any number of problems using firewire and the 1200A =and my many conversations with the techs at Panasonic have not made me any too confident in trusting my HD workflow to firewire if it can be avoided. I’ll take any theoretic loss when using HD-SDI in exchange for it’s stability. In the case of 720P30 I’m seemingly stuck with firewire and am just trying to survive.”
Cool. Those are very valid reasons for not using a native workflow. I just get annoyed when people think that HD-SDI -> DVCProHD is native. And a lot of people do think that.
That’s strange that the Decklink can’t do 30p. One other thing you could use is the Panasonic Frame Rate Converter Utility. Or you could just edit your 60p footage on a 30p sequence.
Sean
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[Sean ONeil] “I have no problem with your workflow whatsoever. I do have a serious problem with false information being proclaimed by a Cow leader. HD-SDI capture is not native, and the definition of “native” is not in dispute.”
You can call it what you want, I can tell you that working in HD-SDI is as “native” as capturing Firewire. If anything, it’s cleaner coming in HD-SDI. Strange but true.
I don’t consider it false information if we’ve used the workflow on about 100 HD Broadcast Masters to date and I can confirm this process works and is incredibly clean. I consider “native” to be anything that can faithfully replicate the original format. The AJA Kona boards can do this and I believe the BlackMagic boards perform the same process.
I spread information that I know works. If you want to use Firewire because you consider this the only “true native” workflow, that’s fine. But HD-SDI is a very valid workflow and I very much consider this a “native” workflow.
[Sean ONeil] “Again, I’m well aware AJA thinks you should use their products for every workflow. No shit they think that. They have families to feed. I didn’t want to engage in this discussion but this kind of false information just annoys the crap out of me.”
Comments like that about AJA annoy the crap out of me too. AJA is the first to tell you when you should and should not use their gear. For DVCPro HD you do not need their equipment and they’re the first to tell you that.
At this point I’m done with this discussion but I’ll be glad to jump into the next thread to discuss native DVCPro HD editing, whether firewire or HD-SDI.
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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[walter biscardi] “You can call it what you want”
That’s your problem. You’re calling it what you want, not what it is. Firewire capture is native. SDI capture is not. You’re free to say a BMW is as good or better than a Mercedes. But you don’t call a 525i a Mercedes, because it isn’t. It’s a BMW. You’re confusing semantics with actual defined terminology.
[walter biscardi] “I don’t consider it false information if we’ve used the workflow on about 100 HD Broadcast Masters to date “
What does that matter? I created hundreds of broadcast masters in the 90’s using a Media 100 and a BetaSP machine. The client always had the BetaSP masters dubbed to D2 at a local facility prior to creating hundreds of dubs that were sent all over the world. That didn’t give me license to say “My BetaSP masters are digital.”
[walter biscardi] “Comments like that about AJA annoy the crap out of me too. AJA is the first to tell you when you should and should not use their gear.”
In my experience they’re a great company. I was basing my comments on what they allegedly told you. I didn’t want this to get ugly. So let’s drop it. I’ve already said there’s nothing wrong with your workflow. My only problem is the misuse of terminology.
And if you want to know why I’m so militant about this, one time I rented out my AJA-1200A to someone for a week. It had the FW option but not the SDI. He brought it back the next day because his editor told him using Firewire is inferior because it re-compresses the video, and that you need a Kona to maintain the full quality. I would not be shocked if he was one of your readers.
Sean
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Walter –
Thanks for the suggestion, I’ll try making my own 720P30 capture preset.
Herb Sevush
Zebra Productions -
[Herb Sevush] ” What doesn’t exist, surprisingly, is a blackmagic easy-setup for 720P30. They have one for 720P60 and 720P24 but nothing for 30. “
AJA is the same way. No worries, onus is on us to change it.
[Herb Sevush] “They play fine in a 720P30 timeline but in the viewer and in the browser they indicate having 60 frames.”
Where?
[Herb Sevush] “I’ve never edited in 720P30 before and I’m tryihg to figure out if this is normal or I’m having a problem.”
Nope. No problem.
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[Sean ONeil] “I mean, it’s almost like saying “A few reps from McDonald’s development team told me that Big Macs are are actually heathy for you.” “
What? Not at all.
[Sean ONeil] “HD-SDI capture is not native, and the definition of “native” is not in dispute. “
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.
[Sean ONeil] “The only way it can be called native is if the 1’s and 0’s on the tape are 100% identical to the Quicktime file you have captured.”
Oh yeah? So when Quicktime decodes it, it’s an exact duplicate? How so?
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[Sean ONeil] “Cool. Those are very valid reasons for not using a native workflow. I just get annoyed when people think that HD-SDI -> DVCProHD is native. And a lot of people do think that. “
I don’t think that’s the argument.
[Sean ONeil] “That’s strange that the Decklink can’t do 30p. One other thing you could use is the Panasonic Frame Rate Converter Utility. Or you could just edit your 60p footage on a 30p sequence.”
You can, you just have to make the easy setup, same with AJA.
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