FCP /iMac for Broadcast?

[Shane Ross]

Sorry, but no…you can’t do uncompressed SD (nor HD) work with an iMac. Sure, you can get the AJA I/O that can capture uncompressed footage and send it down a firewire cable, but…what do you capture to? First off, all the firewire ports on the iMac are on the same bus. Second, it only has firewire 400, and for uncompressed SD work you need AT LEAST firewire 800…but most preferable an external SATA Raid or fibrechannel array. But for those you need a SATA controller card or fibrechannel card. Neither one will go into an iMac, for all you can add to an iMac is more RAM.

Sorry…you are gonna need a G5 tower and other equipment for broadcast SD work.

(Who said editing was easy?)

[The Bill]

Thanx Shane, can you or anyone elaborate on my response?

Sorry, but no…you can’t do uncompressed SD (nor HD) work with an iMac. Sure, you can get the AJA I/O that can capture uncompressed footage and send it down a firewire cable, but…what do you capture to?

The spots are mostly animation (created in the computer) combined with short bits of live action…so, at this point, I’m only working with short clips (a few secs long, probably a few gigs at most)…basically I was going to capture the footage using the FW I/O and send it to the internal HD, cut it in FCP (at low res), then render the final sequence with settings as an uncompressed QT and kick it out to tape. I’m guessing it might better and cheaper to receive the footage as a data DVD or even via ftp, edit it in FCP, then burn it back to a DVD as an uncompressed QT and let a post house master it to tape….any thoughts?

This is from the AJA website and it’s why I thought it might be a possible work around from using a post house for short projects that need to be mastered on beta…
… How does Io transfer uncompressed video over FireWire? It efficiently uses the IEEE 1394a 400Mb/s FireWire port on the Power Mac for all data transfer

[Alessandro Capitani]

[Shane Ross] ”
Sorry, but no…you can’t do uncompressed SD (nor HD) work with an iMac.”

Shane,

I disagree. I have seen a demo on the Aja booth at NAB ’05 showing a Macmini doing uncompressed!

The unit had a Io-LD on the mini’s FW port and a GRaid disk on the USB2 bus. The result seemed to work flawlessly even if I have to admit that of course the above is far from an ideal enviroment. So if the Mini can do, why an iMac shouldn’t? The iMac is G5 equipped with a more robust architecture.

Again, the statement that you can’t do uncompressed in Firewire 400 is wrong, tha Aja IO has been designed with FW400 from the beginning.

My 2 cents.
Alessandro.

[Frank Nolan]

Not too sure about using a usb drive to capture uncompressed but if it was working flawlessy that could be good news. Bill the problem is the AJA Io uses the firewire bus and doesn’t like anything else on the bus with it. Even though there maybe FW400 & 800 ports on the imac, they are still on the same bus, so although it can work in some cases, it is not recommended to have FW drives on there as well. Now if you intend capturing to the internal drive, which is not recommended, then you may get it to work.

>cut it in FCP (at low res), then render the final sequence with settings as an uncompressed QT and kick it out to tape.

Not sure what you mean there but if you plan on digitizing at low res, then you would have to re-capture the final sequence at high res, uncompressed.

[David Chai]

You could always use the DVCPRO 50 codec which is very nice or else the photo jpeg codec at 75% to preserve the quality of your graphics and work within your system, but at much lower data rates than uncompressed. Then just output to beta from the AJA io.

David D:

—————–
David Chai
Director . Camera . Editor
http://www.davidchai.com
dc@davidchai.com
212 363 0159

[David Dubois]

Another alternate would be to get the beta’s digitised at a post house (overnight for the lowest costs) and have them export an image sequence for you. That way you still get the best quality but you have a more imac/fw400 friendly version of the media.

Dave

[Graeme Nattress]

I doubt an image seq would be more friendly…

If the mac is up to it, a PhotoJPEG75% capture will be more than good enough for BetaSP, as would DVCpro50

Graeme

– http://www.nattress.com – Film Effects and Standards Conversion for FCP

[Kelly]

I think what hasn’t been explained to you so far is: even though the IO and Firewire have enough bandwidth to send an uncompressed signal down the wire, the internal drive on the iMac isn’t fast enough to reliably record that signal and play it back without skipping. You would need an external group of RAIDed drives to handle that much data, but external drives generally use the Firewire connection (which you have already saturated with the IO). You could use a USB2 port for your external RAID like another has said, but this generally isn’t ideal. The fella says it works and I believe him, I’m just telling you that this generally isn’t done and would be really pushing things to their limit.

The simpler solution is to compress the signal upon capture. This frees up disc space, let’s you work with slower hard drives, and is still very good quality (better than the DV you’re used to). Having said that, it is a bad idea to capture video to the same drive your operating system is running off of. Again, it can be done, but it isn’t recommended.

[David Dubois]

Hi Graeme

I have found that images sequences run smoother on lower spec machines.
Png’s seem to work well for me.

I suppose it might be me willing the machine to go faster that’s causing it!
🙂

Dave

[Graeme Nattress]

FCP doesn’t even support image sequences…. You’ve got to hack it together by a string of 1 frame still image imports, or use Quicktime Pro to convert to a video codec.

Graeme

– http://www.nattress.com – Film Effects and Standards Conversion for FCP