Are these Image files?
Is most of it getting put away and then does not get adjusted again, or is material routinely getting changed after it has been archived?
I'd suggest that he's in the market for an 8-bay Burly box or two, filled with 750's.
I think a duplicate set of 750's would be the first backup. I'd use something like Chronosync or SuperDuper to automatically back this stuff up as drives get filled. I don't know the tape drive landscape, but I assume that this would be the best option for the third copy. I guess Blu-ray is possible as well.
Yes, these are image files. His current workflow is to download his cards from a shoot to a folder on his "ingesting" G4. This is typically 15-20 GB of data, from multiple cameras. Then they get lined up according to date/time from the EXIF data and renamed with a new unique identifier. At this stage they get burned to write once media and copied to an external FW drive. The problem is where to put this ever-growing archive, and then how to back this up.
I'm currently pitching a 5 bay Sonnet Fusion enclosure (the port multiplier is attractive to me) filled with 500 GB drives, with the possibility of additional trays and drives for off-site backup. That will give him two drives for originals, two for derivatives, and another drive for working backup if necessary (the 1 TB internal RAID is already getting backed up regularly to an external 1 TB RAID). Not sure if this is going to be enough! But the price difference between 500 and 750 GB drives is significant. Thoughts?
I think tape is still a good cold storage solution, but for quick access nothing is faster than a HD. Steve says there is some new longevity data about drives that are shelved for extended periods of time? I'd be interested in seeing that.