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High Definition Video for Independent Filmmakers
A How To Guide for Digital Filmmakers
Welcome all! This is my blog to share my latest research,
thoughts, etc. on utilizing HD for independent filmmaking.

YES, I am available for consulting
Contact me at mike@hdforindies.com

All content copyright 2004-2007 Mike Curtis.

Thursday, October 04, 2007

Low Cost RAID 5 - I think we're getting there. 

For a few years I've been writing about using SATA based RAIDs for uncompressed HD projects. Slooooooowly but surely, some RAID 5 (fault tolerant, don't lose all your data if a drive craters) solutions have been coming to market.

At first, they were PCI only (during the PCI-X G5 years). So they were too slow for uncompressed HD (this was before DVCPRO HD native editing was popularized).

Then there were PCI-X cards, but they were still too slow - 80-110 MB/sec write speed for RAID 5 - far too slow for the serious work I wanted to do (10 bit 1080i60 is about 160 MB/sec, need about 200 MB/sec throughput for reliable performance with overhead).

Then I got a Highpoint card, which was a bit slow - one of the 1800 series something or other cards (I'm writing this in Newark airport on way to Spain, can't exactly look on the Shelf Of Old Tech to check).

Slowly but surely, more choices. I recently visited a client's shop that had been running one of the newer Highpoint cards (the 2314 was it?) in RAID 5 mode with PLENTY of throughput for uncompressed HD.

I just read this review on CalDigit's HDPro, the writer runs it through its paces with an 8 bit 1080i60 onlining project.

Then I got an 8 drive, 4TB review unit from Dulce that I am overdue to finish my write up and return the unit, but it has been performing splendidly as well.

I think we're there in terms of affordable, fault tolerant storage. They don't have the maintenance features we'd like, you should probably still wipe the RAIDs between projects (still utterly unrealistic in most working situations with overlapping jobs), but the price is getting closer to doable for a broad swath of budget constrained indies.

Give it another year or so for fault tolerance to be a "yeah, of course, throw that in" option on storage.

I'll have more to say when I publish my full Dulce unit review when I get back from Sitges (Spain).

-mike

UPDATE Shane Ross wrote in to ask how I missed his review, in 4 places no less, of the same CalDigit review.

It is MUCH more thorough, go read that one for a better explanation and better testing, including throughput testing on both a mac Pro (over 300 MB/sec!) and a laptop (over 150 MB/sec. Laptop!).

Here's his:

LITTLE FROG IN HIGH DEF: REVIEW-CALDIGIT HD PRO

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Comments:
Hi Mike,

Could you please explain to me what you mean by 8 and 10bit video?


Whenever I read about it, I'm sure you're referring to how many different colours. When I ask my editing teacher about it he says computers work in 8 bit, so the video is taken from 10 bit, to 8, and then outputted back at 10 bit again, and that this doesn't change anything, it's just a different way of processing.

But I thought if capturing 4:2:2, or 4:1:1 that video would have a 8 bit colour space, but you capture it in 10 bit, so when you colour correct you have more room to work with?


Ok, please help.
 
And G-tech released one too

http://www.g-technology.com/Products/G-SPEED-es.cfm
 
Hi Mat,

Computers do work with multiples of eight bits. So a ten bit sample would be stored it two bytes; sixteen bits. This leaves six bits unused. So each of the three primary colors could take two bytes each for a total of six bytes or 48 bits.

Or you could pack the ten bits times three primary colors together into 30 bits which fits nicely into four bytes leaving two bits unused.

Here's some articles that might help a bit.
http://www.kenstone.net/fcp_homepage/basic_codec_jordan.html
http://www.powerthinkinginc.com/New%20Pages/article8.html

I hope this helps.

Rob:-]
 
Michael - yep, and I'll have a review unit waiting for me when I get home.
 
the g-tech drives look great! It's Mac-pro only though ... :(
 
These turnkey systems seem expensive, especially with the hard drive prices falling the way that they are. I was looking to build a RAID 5+0 system with the following:

EnhanceBox E8 Multilane case $600.00
2 x Mini SAS - Multilane cables $100.00
8 x 750 GB drives $1800.00
RocketRaid 2322 PCI-e card $250.00

Total: $2750.00

For 3 TB of RAID 5+0. This is almost half of what a 3 TB turnkey system goes for. Unless I'm missing something, and any info is helpful.

Thanks
Graham
 
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