Incidentally, my system started out on Unix systems, moved to OS X using iView, and now is managed with a mixture of iView and Lightroom. Originally the IDs were rendered as hexadecimal numbers (e.g. N1_211A was allocated on the machine "N1" and is image 211A [8474 in decimal]) to render shorter strings. On the systems I used to use, filenames were sorted as a single string, and thus N1_211A, N1_2119, N1_2000, and N1_2120 would be sorted as:
which is the order they were allocated in. However, at least on OS X these days the sort order has been changed to be more "user-friendly" and they instead get sorted as:
- N1_211A (the software is identifying the "211" as a number, trailed by an "A")
So I've had to change back to decimal image IDs so that images will be sorted correctly within each minute...