Uncompressed FX1 / Z1 video
 

As we all know, the FX1 / Z1 records to tape in the MPEG 2 (compressed) format.
I was at a video exhibition in London today and I asked the people demonstrating the Z1 if it was possible to stream raw, uncompressed footage from the Z1 (to reduce artefacts, etc). They said it was NOT possible, but I just searched the net and someone says that it can be done with the “BlackMagic DeckLink”. I went to their site (http://www.blackmagic-design.com/site/decklinkhd.htm) but I can’t work out for sure if it is possible.
Does anyone know for certain if it can be done? Also, does anyone know if such devices are available for the PC?

Thanks

yes it works

The only problem is that you'd need to lug your PC around I guess. =P

As stated the system is possible but you need to consider a couple of things.
Will the system be for capture only or do you want to edit on it as well and next, how portable does it need to be?

Either way if you’re looking to use a HD capture card from Blackmagic it must slot into a 64bit/100Mhz or 133Mhz PCI-X slot.
These are mostly dual G5, Xeon or Opteron boards.
You could also use a Kona2 capture card for the G5.
To begin you’ll need either an AJA HD 10A or a Blackmagic Multibridge to convert the ‘live’ HD component out to HD SDI.
You must capture the component live as if you don’t it will have gone through mpeg2 compression.

Next if you want to use this system for capture only at say 10bit 4:2:2 you’ll need either a scsi or sata array capable of capturing 500GB at 135MB/sec for 2 hours (say).
It’s also fair to say here that nobody outside Sony Japan knows for sure with the ‘effective’ bit depth and colour space of the FX1 component out is.
Sure it won’t have gone thru the mpeg2 encoder but it could well be ‘effectively’ anywhere between 8bit 4:2:0 and 10 bit 4:2:2, probably!
If it’s going to be your edit system as well you’d probably be best using something similiar to what Blackmagic suggests on their site.
The cheapest capture only xeon system I’ve seen that ‘should’ do it is a Dell 1420 for $450.
If this system is a xeon capture only you’ll only need one cpu as you’ll be using DMA. Ask BM for other G5, Opteron capture only specs.
For the drives you’re key areas are i/o bandwidth and backup and of course $$.
I’d look at trying 4 x 300Mb Maxtors Maxlines.
Find a sata controller that let’s you do Raid 0 and raid 1 on the same physical drives.
Make the first (outer partition) Raid 0, say about 1/3 of the drive and the inner partition Raid 1.
Backup as you go!
Or you could go for a 8 port sata controller and have an additional external raid 0 partition to shuttle back and forth with your main NLE system.
Needless to say you have a lot of storage options!
Personally I’d like to see how those scsi 2.5” 10K 250GB Hitachi sonatas go. I heard they handle shock of 500Gs!!
Another thing I’d like to investigate is using 8 sata drives, 4 internal and 4 external. See if you could create an 8 disk, raid 1 partition over the fastest (outer) section of the drives, and then use the 4 external drives as a copy to be used with your main NLE. Not sure if it’ll work but worth investigating
Remember you’re capturing at 134MB/sec so when you’re transferring data, Firewire or 1Gig Ethernet it’ll take 2.5 times the length of the footage to transfer, if that makes sense.
Last is batteries, that’s if you want it portable. Well if you really want it portable I’d be looking at some of those industrial SFF single xeon boards but that’s another thing!
You’ll need Lithium-Ion battery arrays capable of 250W for 2 hours. These have a good power to weight ratio.
I suspect the batteries, battery controller and atx converter will cost around 1500.

You do realize no one is doing this stuff at such ridiculous cost. A portable 10bit uncompressed 4:2:2 SRW1 costs about $95,000 and we’re talking about $5~10K for a portable recorder.
That’s progress!

Dave Farland

Wow, David, that's a pretty comprehensive answer!

If you have seen the documentary on the DVD of the movie "Russian Ark" you will know what recording a 90 minute uncompressed HD movie in a single take requires... About eight people were dragging about 400-500 lbs of equipment around 2 miles of the Hermitage museum in St Petersburg with temperatures of -20C outside!

However, while I appreciate that if you were going to spend two hours recording in any one session, you would need to drag about a LOT of kit, my idea would be to have half the kit (i.e. half the disk drives, half the batteries) and only record uncompressed when you are sure that you are likely to use the footage that you are shooting. Usually, with video, you are not to worried about using a lot of tape as it is re-usable and cheap, but treating the uncompressed footage as if it was on film would put you in an efficient shooting mindset...

They say that Hitchcock used half the footage he shot in the final movie (an efficiency of 50%). People shooting on video probably have an efficiency of 5% or less! So, if you are prepared to shoot test footage and rehersals on tape and save hard-drive space for the "real thing", then a portable uncompressed setup could be viable.

As to price, I think that (based on your specs) a one hour uncompressed, portable storage system could be made for as "little" as $2000. Whether this is good value for money depends on how much you value the difference in quality!

Considered as an investment, such a system, when used in multiple productions (and maybe hired out), could be not only viable, but valuable!

Thanks for your input!

While the topic is raised, I'm curious:

You can take the live component out on an FX1/Z1 and sample (in a low noise environment) some form of uncompressed HD video on a high end consumer PC, hack the camera and equip it with a lens with less chromatic aberation... It strikes me that for less than $10k you could work up a 1440x1080i uncompressed video HD cam that is reasonably portable.

What is the cheapest "real" system (i.e., one that provided uncompressed 1440x1080i or better) available from a manufacturer?

-Steve

Leitch VelocityHD: Boardset/software is approx $10,000
The Media 100 HD: Boardset/software/break-out box is $8,000
HD Fury: Boardset/software is approx $12,000
Kona2: Boardset is $2,500*
Decklink HD Pro is $1,500*
* requires Decklink Multibridge ($2,000) for analog video/audio capture. The multibridge is nice because it'll imbed your audio into the HDSDI signal.

These boards will capture uncompressed 10bit 4:2:2.
If you want ‘real’ HD turnkey version of these boards/software add $8,000~10,000 to the price. Nothing portable here.

Dave Farland

Here is close to the cheapest Mac system you would need:

1x 1.8Ghz G5 w/ 1GB ram $1750
1x Decklink HD I/O card $500
1x AJA HD10A $1500
1x 8 Channel SATA RAID controller $300
6x 300GB SATA drives $1200
Adapters to mount drives inside G5 $600
1x Final Cut Pro HD $999

Total $6849

All you need for this application is a single link HD-SDI card and the Decklink Hd is the least expensive and works just fine.

This system would give you 1.8TB of dsik space to capture to.

Dustin, I dig your list. Do you have this equipment now?

I've got the G5 and FCP HD. But, the other stuff is now on my wish list. Can we squeeze by with Firewire 800 drives? If so, we're all looking at about $2500 after a Mac/FCP purchase.

Chris,

I have a dual 2.5Ghz G5 instead of the 1.8Ghz G5, but the 1.8 does just fine.

I also have a Decklink Multibridge instead of the AJA HD10A. THe Multibridge cost about $500 more, but it does a lot more. Well it will do a lot more once Decklink gets it working correctly.

I also have a JVC 19" HD studio monitor ($2500) for editing and color correction. You can live without this, but it is very nice to watch HD on a good HD monitor and it is required for proper color correction. I convert the HD-SDI signal from the Decklink HD card to analogue YUV using the Multibridge for viewing on the monitor. The Multibridge can convert analogue to digital from the camera while at the same time converting digital to analogue for viewing on the monitor. It is very nice!

The only thing I don't have right now is the 1.8TB of internal disks. Without that I can't do 10bit uncompressed HD.

With firewire drives (25-80MB/s) you can do 1080i DVCPRO HD (14MB/s) just fine.

Since we are shooting 8bit MPEG-2 compressed HDV, it seems that 8bit DVCPRO HD compression would be good enough. I need to do some real test of capturing HDV to DVCPRO HD and 10bit uncompressed to see how much of a difference there is.

10bit would be great, but I have to justify another $2000+ in harddrives and I don't know that the quality difference will be noticed by the audience.

That's really interesting...so, basically we have everything. I've got the dual 2.0 gz machine, so we just need external firewire drives. Even then, we only need 400 drives right? The last I remember, G5's run Firewire 800 drives like crap. I'm not sure if that issue has been resolved or not. Know about that one?

Chris,

Firewire 400 is just fine.

The Firewire 800 problem was fixed on the 2.5Ghz G5, but is still not at fast as Firewire 800 on the G4. As far as I know all G5s before the 2.5Ghz have terrible onboard Firewire Performance. The simple fix is to buy a firewire 800 add-on card.

All you need is:

Decklink HD $500
AJA HD10A $1500 or Decklink Multibridge $2000

And you can capture DVCPRO HD to Firewire HD from any analogue HD source.

DVCPRO HD is about 50GB per hour versus 12GB per hour for DV25, so you will more disk space than with DV25, but a single drive is fast enough.

Actually a single 400GB SATA drive as a second drive inside your G5 should be able to handle about 7+ hours of DVCPRO HD footage.

Thanks for the info Dustin. I expect DVCPRO HD will give very good results
I suggest the Multibridge over the AJA because it'll inbed the analogue audio from the FX1/Z1 into the HDSDI signal .

Or you can use the Decklink HD pro capture card and a digital source.
Or, I'm not sure about FCP but can it capture timecode and even audio from the firewire input or audio from an independant sound card at the same time you're capturing the video from the decklink card?
If you've sync'd from the camera I guess you'd just use the audio from the HDV tape. There are other solutions i.e. lanc but I'd hope these would be cheapest.

Dave Farland

David,

I recommend the Multibridge over the AJA HD10A also.

As for audio, in FCP you can either capture:

1. embeded audio from the Multibridge

2. DV audio from the downconverted HDV footage

3. Audio though an external sound card. I have a MOTU 896HD.

FCP is very flexible about where the audio, video, and deck control come from.

Once the Multibridge has been replaced and is correctly working I will do some more tests to see which way is best for me.

The Multibridge is set to -20db so all of our captured audio is about 16db below where we want it. I am looking into the best solution to work with this. Right now I have my Sound Devices 302 field mixer between the camera and the Multibridge and that works.

The audio in the downconverted DV footage is just right, so maybe using the DV audio will be the best solution.

As mentioned in the Barefeats website:
http://www.barefeats.com/hard35.html,
the internal SW RAID 0 in a Mac can deliver a sustained 114MBytes/s with only two SATA drives and between 184 - 232 MB/sec with 4 drives and a PCI controler.