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Anyone get theirs yet?
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[gary adcock] “it is not frame accurate for editing in its native space.”
I don’t know why you say this. My tests with HDV and Matrox Axio show frame accuracy on re-ingestion.
There are issues with the Sony camera if you ingest over camera turn offs with quick record on. In taht case there is a gap on the tape time code on the far side may be off depending on how your NLE registers timecode on ingesting. But if you don’t croos those time code gaps when ingesting the t/c is frame accurate.
David
AllinOneFilms.com -
[toke lahti] “I hope Panny (or someone else) will release finally 16:9 sq.pix recording format for lower price cameras.
Hvx200 could already had 1280x720p24/25/50/60@4:2:0@100Mbps, which I believe would have been optimal combination for PQ with its ccd’s and recording datarate.”Good points. couldn’t it do 4:2:2 though?
Mike Brennan
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[David Cherniack] “I don’t know why you say this. My tests with HDV and Matrox Axio show frame accuracy on re-ingestion.”
Sony’s HDV is a 12 or 15 frame Long GOP structure does not accurately represent the data prior to it being recorded to tape.
I too can capture HDV shot content in an uncompressed state, but even that capture shows the Mpeg encoding to missing some relevant temporal data when compared to the very same non-HDV captured content.In a pro-editing environment having one real ( I frame ) every 15 frames ( 12 for PAL) during any capture is not what I would call frame accurate, not in my editing environment. Editing in the Native HDV codecs (over FW) require the computer to regenerate the “missing” info.
Additionally since FW control is not Frame accurate on any platform and with only one Tape deck ( from JVC) offering RS 422 serial deck control for editing purposes, how can any FW (1394) editing be frame accurate? The protocol you are using for your deck control is only accurate to 3 frames under optimal conditions.
Gary Adcock
Studio37
HD and Film Consultation
Chicago, IL USA -
Gary,
The proof, as they say, is in the pudd.
In my tests I captured from the Z1 via FW a DV downconvert, then captured via firewire the same material – pans of birds in flight – as HDV. Frame Accurate every single time.
This is to Premiere Pro though I seem to recall rumblings from FCP users about frame accuracy. Perhaps you’re referring to that.
There’s no inherent reason why captures from firewire, mpeg or mjpeg shouldn’t be frame accurate. The t/c is inherent in the signal.
Inserts to firewire devices are a different story.
David
AllinOneFilms.com -
[David Cherniack] “In my tests I captured from the Z1 via FW a DV downconvert, then captured via firewire the same material – pans of birds in flight – as HDV. Frame Accurate every single time.”
the hardware spec for FW does not include the ability to lock to a SYNC signal. The FW spec for deck control varies for different computers and devices. The inherent latency of the FW protocols vary from.5 tro more than 4.5 frames depending on cable length, machine, number of devices on the chain, where or not there is a sync signal
That you recaptured material on the same machine twice via FW does not mean that it is frame accurate for editing, Not for a professional editor. It does mean that your machine can recapture the same content in the same manner from the same device consistently. Move that content to a different machine or transfer that as an EDL to some other machine – and I have more than serious doubts that it would have the same accuracy.
[David Cherniack] “There’s no inherent reason why captures from firewire, mpeg or mjpeg shouldn’t be frame accurate. The t/c is inherent in the signal”
In theory david you are correct. but there is a lot of fudge in the way different manufacturers handle the data flow and that means that every single device protocol is a little different.This is not an issue with Timecode. it is an issue with serial data protocols being converted to FW and back again.
And it is not a MAC vs PC debate –it is a hardware issue independent of both of those things.Gary Adcock
Studio37
HD and Film Consultation
Chicago, IL USA -
[gary adcock] “That you recaptured material on the same machine twice via FW does not mean that it is frame accurate for editing, Not for a professional editor. It does mean that your machine can recapture the same content in the same manner from the same device consistently. Move that content to a different machine or transfer that as an EDL to some other machine – and I have more than serious doubts that it would have the same accuracy.”
Gary, in fact the downconverted and HDV clips were captured on different computers. PPro and the Z1 were the same, however, so you may well be right that different software and decks will do things with varying degrees of accuracy. My experience however, would seem to invalidate your general statement that capturing via firewire is not frame accurate.
[gary adcock] “And it is not a MAC vs PC debate –it is a hardware issue independent of both of those things.”
I don’t recall bringing Macs or PCs into it. I did mention reading (on the HDV forum) that FCP may have accuracy issues with capturing via firewire. Or maybe it was specifically with the Z1 . But surely we can mention apps without raising platform issues.
David
AllinOneFilms.com -
[David Cherniack] “Gary, in fact the downconverted and HDV clips were captured on different computers. PPro and the Z1 were the same, however, so you may well be right that different software and decks will do things with varying degrees of accuracy. My experience however, would seem to invalidate your general statement that capturing via firewire is not frame accurate”
David, I am going to imagine that I have experience on a wider variety of hardware and software, I have been the person fixing HDV captured when it has failed the network standards for transmission because it landed a field off. (that would be 1/2 a frame).
In the working world that I live in, FW is not considered frame accurate even for SD, ergo it cannot be any better for HDV. I will not live with a +/- variance of somewhere between 2-5 frames with device control over FW when I can use serial control and get guaranteed accuracy.
Let me also state that I come from “real” HD, I get to work with VariCam, HDcam, SR, Viper and other hi-end solutions. I think that HDV is a great beginning step for DV shooters, but I see it for what it is, and unfortunately it is a consumer format.
Gary Adcock
Studio37
HD and Film Consultation
Chicago, IL USA -
[gary adcock] “(that would be 1/2 a frame)”
Gary,
You should realy do a check on someone when you feel the urge to explain what a field is to them. Irregardless, you just don’t seem want to accept that Axio and PPro can be frame – no let me say ‘field’ accurate. Fine. There’s precious little I can add to that discussion then.As for your statement that “I think that HDV is a great beginning step for DV shooters, but I see it for what it is, and unfortunately it is a consumer format” it just betrays an elitist attitude to a format that has some built in shortcomings but with proper care in shooting and post can look terrific and work where varicams, sr’s and vipers can never go. Many of us will continue to use it as a professional format and chuckle at those who say it’s not.
David
AllinOneFilms.com -
[David Cherniack] “You should realy do a check on someone when you feel the urge to explain what a field is to them. Irregardless, you just don’t seem want to accept that Axio and PPro can be frame – no let me say ‘field’ accurate. Fine. There’s precious little I can add to that discussion then.”
Sorry if you’re offended David, as a leader I try and post so that everyone know what I am endeavoring to talk about.
I have had to clean up more than one project that was booted from broadcast because it ended on the wrong field. (and it is my understanding the PPro by itself cannot edit at the field level)I have also explained that what I keep talking about in inherent in the FW protocols within the hardware, not with any application or platform combination. I do not know of a single company -Adobe, Apple, Avid or whomever that claims that FW is 100% accurate at deck serial protocols.
I am glad that it works for you, I can assure you however does not work for a large number of people and I believe that anyone attempting to work in ANY compressed codec in HD understand all of the possible problems they may encounter. This is one of many that crop up when working with HDV content.
Gary Adcock
Studio37
HD and Film Consultation
Chicago, IL USA -
[Michael Brennan] “couldn’t it do 4:2:2 though?”
With 1080p60@100Mbps there would be too much compression. Or maybe with jpeg2000…
And where do we need better vertical resolution than horizontal?
Square pixels sound logical to me.
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