Editing uncompressed 8-bit - what drive do I need?
 

Hi all,

I use FCP 5 on the Mac and more and more I need to edit HD. What kind of hard drive / card configuration do I need to effectively look at 8-bit uncompressed footage without hickups. An 8-bit uncompresssed data rate is usually around 440 Mbits/ sec.

I usually edit HDV source 1st into a rough cut, then I do color grading and effects in a 8-bit uncompressed timeline, this is where I would like to do my monitoring, but for this I would need a super fast drive to push all that data through.

Anything you use? Any recommendations? I've seen hard disk/ PCI card systems that go for $3,000 - but I don't want to spend that kind of money. Do I have to?

Is a G-RAID2 7200 RPM SATA II hard drive with 16 MB of chache Firewire 800 good enough? Currently these go for $500 for 500 GB.

Thanks!

What type of Mac are you editing on?

I think you will more than likely need a multi-drive raid solution for 8-bit HD.

Yes, sorry. I have a dual 2.7 Ghz G5 with 1 GB RAM.

"An 8-bit uncompresssed data rate is usually around 440 Mbits/ sec." I think 440 may be a little high for the data rate and sounds a bit more like how much space is needed per hour of footage. 8bit 720/60P is about 105 MB per/sec and 8 bit 1080/30P is around 119 MB per/sec, give or take depending upon your frame-rate.

Without getting to deep into off the shelf, pricier solutions, a best bet that would maintain the data rate to stream one layer of 8bit uncompressed would be this:http://www.transintl.com/store/categ...egory=2490#top. Coupled with four Seagate Barracuda 500GB SATA drives, you'd have a relatively budget solution that would tide you over until you're ready for a pricier solution.

Also check http://lfhd.blogspot.com/2006/12/dar...sata-raid.html by DVinfoer Shane Ross about his journey to find a cheap uncompressed RAID solution.

bits and bytes
 

Many thanks Tim! Great resources and useful info. I like the cost of the Swift Data 200, looks great. Looks like this solution can really drive an uncompressed HD data rate.

I am correct and I think you are reading Megabits as Megabytes...

440 Mbits is HDCAM SR datarate or 55 MB/ sec (that's MEGABYTES) - I also checked the Quicktime player info on an 8-bit uncompressed clip (720P) and confirmed it said 440/ megabits per sec.

that's why I usually spell out "Mbits" because people usually confuse MB for bits or bytes and it's a huge diff.

Thanks again!

Miklos, you are correct my friend. You would think that after all the time I've spent with computers I'd have a handle on bits and bytes, nevertheless bits and bytes will probably continue to baffle me.

-Tim

Just to note, the reason why Quicktime told you 440 mbit/s is because it must have been a 30p clip. 720p is usually at 60p which is where the 110 MB/S comes from. 30p is half of that or 55 MB/S or 440 mbit/s. 440 mbit/s for HDCAM SR is because of the 2:1 mpeg4 compression on the tape. There is no HDCAM SR codec to edit with and the footage is usually edited as just uncompressed or 120MB/S. If you plan on capturing uncompressed 720p then it will have to be captured as 60p. You will need at least a 4 drive raid to handle this for a decent sustained amount of time.

Ah, I see you are not planning on capturing HD but converting what I assume is 30p HDV into 30p 720p uncompressed. You will still need something that can sustain 55 MB/S. I think a G-Raid can sustain that amount but I'm not sure for how long.

It's a tie between an internal solution of SWIFT DATA RAID drives (750GB) [thanks to Thomas] for around $350 and an external "LaCie Two Big" Raid drive 500 GB for $430 - the Lacie was supposed to give me 110 MB/ sec sustained data rates, I only need about 55 MB/s. The idea is that when I'm in 8-bit uncompressed mode when editing in FCP I would designate the RAID drive as my render drive and playback of clips would be sustained without a hick-up so I can check color-correction, effects and such.

uncompressed footage will fill your hard drive up fast - so get as much space as possible.
A 4 drive RAID of 500gig Wester digital SE16 drives is what i use.
You will need more Ram than 1 gig. At least 2 but 3 or 4gigs is better.

How are you capturing your uncompressed footage ?

Thanks Tyson, but if you look through the thread you'll see I'm only looking to use a RAID for uncompressed rendering of a near finished edit (not to capture or store). To check a final cut seamlessly. A 500 GB will give me about 2.5 hours worth of 8-bit uncompressed at 720P 30 FPS (calculated this with the VideoSpace widget from Digital Heaven). Is more RAM really necessary though, why isn't 1 GB enough? The drive supplies the sustained data rate, not RAM, even though it might be used as a cache, a fast drive is more important than the size of RAM as far as I know.