Could "179 -49-" be a geographic coordinate? 179 degrees and 49 minutes is a possible format, but 179 degrees is a very high value for longitude, near the limit. More likely, it is a used to organize an archive's physical or digital holdings.

If you are looking for information regarding a specific historical archive, a particular photography collection, or a technical system related to these acronyms, providing more context about where you encountered the filename can help pinpoint its exact origin.