I have pictures and music literally buried in multiple old incremental backups on a Seagate external drive. These backups were from an old MacBook utilizing an unknown software.
Well first your going to need to determine if you can access these files, or is it locked into a proprietary format.
If they are just regular files buried into many subfolders etc that would be labor intensive to dig out you could go about it using software
Data Rescue 3 ($99) will read the 1's and 0's of all data on the drive (even deleted) and send the output to another drive to be worked on. However you need to check if there is a option to pull everything out of the subfolders and place it on all one directory or not. It's designed as data undelete software so it's supposed to ignore the file structure in it's recovery attempts and just give raw files.
Another piece of software to compare actual file contents (not just by name, watch out for software that only does that)
Decloner will likely be all you need, I haven't investigated either fully to see all their benefits.
Once you have everything on one directory, you can use the Finder sorting to delete duplicate named files with older dates.
Make sure you work on a copy, leaving the original backup alone less you make a mistake.
How do I get to these files since all of those incrementals has made it a chaotic mess?
The question is, how was the backup made?
If it used a proprietary format (eg, Retrospect), then your only solution is to use the same (or compatible) software to extract it.
It it used a open format (eg, tar or pax), then you still need to extract them, but you don't have to use the original software.
If it was a simple file copy, then all you need to do is to find the respective files. You can use Spotlight for this job. For instance, in Finder, select the Seagate drive, invoke Spotlight with ⇧⌘F, set the Seagate drive as the search scope, and type in the search field
and you should get all files in commonly used formats (mp3, aiff). As to dealing with duplicates, there are various tools for it, it depends on what you need—you could even use iTunes.
Great advice. I was able to uncover thousands of pictures and even some mov. and WAV files. That Spotlight method was so efficient I felt like I was missing something but 7500+ images later I'm convinced. I was not aware of the search field till you pointed it out. The format apparently was not anything proprietary. I could not trace the images back to any one full or incremental backup but I suppose it does not matter anyway. Thanks.