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View Full Version : DV & Firewire - read the threads and still don't get it



Sufish
04-28-2003, 09:14 AM
I've read and half understood the threads explaining why the VT, unlike almost all other systems, despite the hightest possible spec workstation, is unable to output via firewire to DVCAM. - As many have noted in these threads, the VT can only see a DVC deck as a camera when connecting via firewire.


And I remain totally confused by being told that to do so is so undesireable that nanny is not going to do the software development to let us do it, despite the constant boast that the wonder of software based VT is that it can easily do anything. (Am I alone in buying a VT with the specific intent of outputting to DVC, only to find It can't ?)
So can somebody with a bigger brain than mine please explain which of the following bits of information is untrue.

A) I render animations in Lightwave and edit them into presentations of our designs to send to our clients.
For this I was hoping to use my new VT2 instead of my rather unreliable old DPS system.
B) Neither I nor the people I send stuff to can justify the investment or maintainance of running a DigiBeta deck.
I have a Sony DVCAM DSR-11 deck. It's playback image quality is vastly superior to VHS. It can record or playback via firewire or composite or S Video. Using firewire I get the timecode too.
Most of the time I send out DVC tapes to people, - finish the rendering overnight, edit, record to tape, hand to the Fedex man. No time to spare to repeatedly render to an avi file and record and play it back to see if it's all right - The doorbell has usually rung by the time I've finished the edit.
If it's a final edit at the end of a big project I get a man with a betacam machine to come in and take it off the component output for duplication and posterity.
C) I have studied the output from the DVC machine very hard, on the best monitors I could get hold of, and neither my boss nor I can see any degradation of image. So we are more than satisfied that it is a suitable medium for archiving our rendering; - sorry, but even with a terrabyte of NAS we do not have room to keep the amount of uncompressed video I generate each month (from 12 render nodes) as image sequences or .rtv files (and anyway I would not risk archiving to a proprietry format such as .rtv, having been caught out befor by DPS's semi-abandoned .pvr format)
D) I have been told - and this MAY be the error - that the digital firewire signal will produce a recording superior to the composite or S Video.
And my brain thinks it can see video degradation using the analogue composite or S video - with the best connector cables I can find - which it does not see using firewire.
E) So although a chainstore home PC can play video onto a DVC machine my hi-spec workstation with VT2 can not.
And the Brains at NewTek are trying to explain why this is beyond the multi-streaming capacity of the VT ?
Yes, I know the digital signal recorded on the DVC is compressed, and therefor is 'less desirable' than the squeaky-clean output of the VT. But this is the real world. DVC is pretty good quality & I want to use it.

Your thoughts please, ladies and gentltlemen ?

SBowie
04-28-2003, 10:17 AM
Originally posted by Sufish

C) I have studied the output from the DVC machine very hard, on the best monitors I could get hold of, and neither my boss nor I can see any degradation of image. So we are more than satisfied that it is a suitable medium for archiving our rendering ...snip

D) I have been told - and this MAY be the error - that the digital firewire signal will produce a recording superior to the composite or S Video.
And my brain thinks it can see video degradation using the analogue composite or S video - with the best connector cables I can find - which it does not see using firewire.


I'm just dealing with the two items that seem to call for an answer, said answer being merely my own opionion...

C - my own experience with animation on DV (or DV-CAM, as you are using with the SR-11) has not been as favourable as yours. But them I am kind of impatient with DV artifacts to begin with. Still, as long as you're happy .... (strikes me unusual most of your clients can even play DV-CAM back, but if they can hooray!)

D - Though 'Firewire' transfer should hold a small theoretical edge, I personally have not seen any significant deterioration when sending the uncompressed video out of the Toaster via S-video to a DV device.

Since you do, though, why would you NOT simply render the finished anim to a native DV AVI file, transfer that (via FireWire) to your DV-CAM tape, use the same tape or backup of the file for achiving, and call it a day? It may be that a later upgrade to VT[3] will permit live DV out directly from within VTEdit, but for the moment you have a number of options that aren't all that intrusive.

mlowes
04-28-2003, 06:19 PM
I wonder if many of the machines T2 users have out there can can already "render" a project out to the DV codec faster than realtime...

Keep in mind the video is already in the DV format when those "chainstore" PC's output to the DV format. Just a file transfer at that point.

I wonder what ever happened to that "Aura DV" feature. You could output your aura projects straight out the firewire port for video ouput sans capture card. It would do live video from your Aura project without rendering. Don't think it was full res though.

vppaul
04-28-2003, 10:03 PM
The Toaster has always been a D-1 Uncompressed machine and DV is being added to the mix because so many people want it. I had great results when I transfered my DV footage in RGB uncompressed into the TV2. I used a sony 1500A with component in and out, I don't remember if the DSR-11 has component in and out. The uncompressed footage looks great, another thing you can do to show your LW footage is to burn it on DVD. I also had great results using the TMPGEnc codec (but only if you read and follow the instructions).

ScorpioProd
04-30-2003, 04:21 PM
No, you are limited to real-time, no faster, when encoding to DV from the Toaster.

I also use DVCAM for my mastering, and I use either Y/C out to my DSR-20 or render first to DV with the MainConcept codec. Originally, I was mainly doing it via the Y/C out, and I never saw any problems with it, but I wasn't doing CGI.

Nowadays I normally render it to DV. The reasons being:

1) Although Toaster works great, I can trust DVing a single clip more without needing to watch or check it.

2) That gives me the file in a realtively small DV size on the computer ready to TMPGEnc for a DVD.