FalconChase Loc: Canton,Ohio, USA

I have a 2015 iMac running High Sierra. I currently have two Seagate back up drives: A 2TB that is used by Time Machine to back up my system. The second is a 1TB Seagate drive that I use to back up PS Elements and Family Tree Maker and other misc. uses. My pictures folder on the iMac is 342GB.

I just purchased a 6TB (2x3TB) Western Digital My Book USB3 drive. My purpose was to move my photos off of my iMac to the Western Digital and do all my editing from that drive. I have two choices, to set it up as Raid 0 for greater speed and storage, or Raid 1 for less storage, a little less speed, but achieving redundancy.

I use Elements 18 and ON1 2017 for photo editing.

I'm looking for opinions as to the best way to set up the new WD drive.

Hank Radt

This might help: https://www.diffen.com/difference/RAID_0_vs_RAID_1

The question basically boils down to: do you want 2x 3tb mirrored drives or 1x 6tb drive with no redundancy.

FalconChase Loc: Canton,Ohio, USA

That is the first question. The second is this, will the difference in speed between Raid 0 and Raid 1 have any significant effect on my using the drive for photo editing?

sloscheider Loc: Minnesota

I don’t think there will be any noticeable difference in speed. My first thought is to do mirroring.

Hank Radt

Was about to respond similarly, but you beat me to it.

Generally, you're only going to notice significant speed differences when your program requires lots of read/write activity to the disk - think video games. However, since you're using these primarily for backup (I think), you're going to be doing most of your work off your internal drives, then saving CHANGES to the external backup drive. Worst case, if you backup a LOT of files, go get a cup of coffee or do the dishes or...

Sorry, after I posted, I noticed that you are going to edit from the external drive (couldn't see the original post when replying). That said, I don't think you're going to notice a lot of difference - typically, if you're editing, you're going to be working on a subset of the images in the drive. Probably more important to speed is the processor and RAM as well as whether you have a USB 3.0 cable, and then less than 10 ft (which is the standard - more than 10 ft and it will slow performance).

TriX Loc: Raleigh, NC

Here are the trade offs:

RAID 0 is striping data across multiple drives. If the data is larger than a single block, a portion of the file is contained on both drives. The advantage is speed. Theoretically (the actual improvement is a bit less because of the overhead of the SW striping algorithm) two drives will produce 2x the speed of a single drive IF the interface is fast enough to support both. Since you mentioned USB3, the interface (480 MB/sec) is likely to be fast enough to support RAID 0 on 2 HDs, even wiTh the USB to SATA protocol conversion overhead. The (big) disadvantage is that since a portion of every file is on both drives, a failure of either drive means you lose all your data unless it’s backed up elsewhere.

RAID 1 is mirroring. The same file is written simultaneously to both drives. There is no speed advantage (unless the implementation allows reading 2 different files from different drives simultaneously and you have two clients actually doing that). The (big) advantage is redundancy. You pay for twice the space that is actually usable, but if you lose one drive, you can continue to access the files on the other drive without interruption. You then replace the bad drive and re-mirror the existing data onto the new drive. It can be considered a form of backup, but no substitute for a 3rd DR copy off-site, and if a file or volume is corrupted or virus-infected, that issue is mirrored to both drives.

FalconChase Loc: Canton,Ohio, USA

Thank you all for your responses. I'm going with Raid 1.

TriX Loc: Raleigh, NC

Safe decision -nothing more important than your data.

jethro779 Loc: Tucson, AZ

Raid 1 is the ONLY way to set it up. Anything else and it's like flushing money down your toilet.

aellman Loc: Boston MA

If your photos are irreplaceable and valuable, add cloud backup to you drive solution. Safety first!

TriX Loc: Raleigh, NC

👍👍 YES. If you have decent internet access, you’d be hard pressed to find more a reliable backup and disaster recovery media.