Storage

Hey guys. New here. Hope to find some good information. As I am just starting out, I was hoping to get some storage preferences for the Blackmagic camera. I've got a budget of one-to fifteen hundred bucks. Was looking at this one:

http://www.google.com/products/catalog? ... CGYQ8wIwAQ

What does everyone think? I like the fact that I can daisy chain more if (when) more space is needed.

[Joshua Helling]

Well, as far as storage goes for the camera to use directly, it's going to need to be an SSD.

We've got several of the Pegasus drives and they are fantastic, but of course they need to be connected to a computer. So if you'd like that for your capture storage it's probably a great option.

I'm going to move this post to the cinematography forum.

On the subject of SSD's - Joshua, are you aware if BMD is going to release a list of suitable SSD's for the camera? I've got a 128GB Vertex 4 as a start - any idea if this will work for Cinema DNG files?

Presently, Blackmagic Design provides a list of SSDs that are qualified (so far) for the camera on this page:

http://www.blackmagicdesign.com/support ... &pid=27542

Thanks stereotank - I did not spot that.

I notice that this list is the same as the one that previously served the Hyperdeck shuttle and other products - some of those SSD's on that list are now discontinued and/or outdated (the Crucial 256GB C300 CTFDDAC256MAG-1G1 is one which appears to be discontinued for example)

http://www.blackmagicdesign.com/support ... 968&os=win

Could someone please clarify what the 'safe' data rates are for Read/Write for those wanting to take advantage of the DNG Raw feature with their SSD's?

Many thanks!

The theoretical data rate is given here:

http://web.forret.com/tools/video_fps.asp?width=2432&height=1366&fps=30&space=raw&depth=12

It is 1.2Gbps or 150MB/s. However, as far as I understand, the camera writes a separate DNG for each frame in raw mode, which is more demanding of the drive than writing just one large file.

Since "RAID" has been mentioned in this thread, here's my obligatory caution:

A RAID is not a backup, unless it's one of at least two storage systems containing identical data.

A RAID is relatively big, fast storage, and may include certain redundancy features for reliability, but by itself it's not a backup. "RAID=backup" is an oft-repeated misconception. So, to repeat: A RAID by itself is not a backup, unless it's one of at least two storage systems containing identical data.

A backup is a complete, up-to-date, identical copy of your data, on physical media or a remote server, that is separate from your online storage. Backups can be on a variety of media, such as individual hard disk drives, HDDs in a RAID, LTO tape, a remote server/cloud, BluRay or DVD data disks, etc.

Ideally you should have more than one set of backups, with at least one located off-site to protect from disasters such as fire, theft, earthquake, flood, etc. That is to say, your original data on one storage media, plus at least one backup on another storage media/system.

Whatever data storage technique you're using, one thing is certain: At some point it will fail.

If you only have 1 backup of your data, at the moment the original storage system fails, you no longer have a backup: You only have 1 copy of the data on one storage system. There's a very real possibility that whatever physical cause, human error, software or hardware glitch that caused one copy of the file(s) to go missing will cause another copy to meet the same fate soon thereafter.

That's why you should always have at least 2 backup copies (in addition to the original data), and keep at least one backup copy off-site.

Cheers.

[Joshua Helling]

Technically RAID means Redundant Array of Independent Disks. Originally it meant Redundant Array of Inexpensive Disks due to the high cost of higher performing SCSI drives.

Almost all forms of raid have some level of redundancy. Only RAID 0, which is not technically a RAID, does not have redundancy. Even so it was given a RAID level because it conceptually fits in the mold.

All raids have varying degrees of efficiency and performance vs security. Efficiency in is how much of the actual drive space is used for non-replicated storage.

For example:
RAID 0 is 100% efficient (you have two 1TB drives and you have 2TB of storage) and has the highest performance, but has no security against failure (one drive down = data boo boo).

RAID 1 is the opposite with 50% efficiency (two 1TB drives and 1TB of storage) and no performance increase, but good security (any drive can fail).

RAID 3 (3 drives minimum) uses an independent drive to store parity (which is used to rebuild in case of failure) with the other drives configured together for performance (three 1TB drives gives 2TB of storage and 1TB of parity). In this config any one drive can fail, but you loose the use of the rest of the parity drive.

RAID 5 (3 drives minimum) similar to RAID 3 performance wise but shares parity across all drives. So the efficiency is higher than a RAID 3, but with a slight reduction in WRITE speeds due to parity calculation. You can loose any one drive in this config and not lose data.

But I digress, this isn't a lesson on RAID.

What Peter says is not wrong. RAID does not = backup. In general I'd recommend that you backup anything you want to save for archive or future use to a separate location (and it too should be a RAID ideally).

I use a network attached RAID 5 at home for personal backups. But I'd do video on a direct attached RAID 5 for performance and sake of drive fail protection.

Everyone's personal needs are different, and both have their place!