On Nov 8, 2014, at 2:55 PM, Ralf R Radermacher <[email protected]> wrote: > >> On Nov 8, 2014, at 2:22 PM, Eric Weir <[email protected]> wrote: >> >> In preparing to move my photo database to external drives I discovered that >> I have 18 Gb of Lightroom Catalog Backups going back to September of 2013. >> I’m guessing that most of these are now useless. How back should I keep >> backups? > > As far back as the earliest changes you might possibly want to undo.
Um, no. The Lightroom's simplistic internal backup system does nothing more than make a copy of the .LRCAT file at the scheduled times into a specified directory. By default, the specified directory is a sub-folder of the catalog folder. For example, if the catalog folder is named MyWork, by default the backup directory will be MyWork/Backups and the individual backups will be in date-named subfolders there, like this: MyWork/Backups/2014-11-01 1116/MyWork.LRCAT MyWork/Backups/2014-11-02 1205/MyWork.LRCAT Each of the catalogs is complete as of the time of its writing, so every single one of them contains the entire history of all the editing done on every image file. It stands to reason that, given the above example, the catalog copied at "2014-11-02 1205" will contain a bit more information than the catalog copied at "2014-11-01 1116", not less, so saving "2014-11-01 1116" will recover no more changes than "2014-11-02 1205" should you need to use the backup. So the right things to do are: a) specify a location for the backup catalogs on your external drive, and b) periodically prune down the backup catalogs to just the last one to save space on the external drive. You do this outside of Lightroom in the Finder (on OS X) and in the File Manager (on Windows). I have my Lightroom catalogs set to create a backup once a day. Every week or so, I go into my external drive where I have it write the backups and delete all but the last one for each catalog. (Note the plural: My usual workflow is based on two catalogs … one for "work in progress" and one for "completed projects" … and I create small catalogs from the master "work in progress" catalog every so often when I'm doing a project or work for a client. If you work in a one catalog workflow, you'll only need to manage backups for one catalog.) Godfrey -- PDML Pentax-Discuss Mail List [email protected] http://pdml.net/mailman/listinfo/pdml_pdml.net to UNSUBSCRIBE from the PDML, please visit the link directly above and follow the directions.
