I have been carefully investigating a way that lets lightroom co-exist nicely with other packages across a range of computers. Specifically I am trying to avoid having to commit to let lightroom force a specific workflow on how I “manage” my photos. I much prefer to be able to browse photos where ever they are. Yet lightroom’s development modules can be extremely useful (at times) so I am keen to let her free but at the same time avoid all her high maintenance demands.
My solution has two parts.\
1) I have decided to only setup the master lightroom catalogues in one place. Yes I have multiple catalogs. I've come to the conclusion that I have too many photos to have a single catalogue. The performance of the library module in Lightroom definitely takes a dive passed around half a million photos. My solution has been to have one catalogue for each year. These may be a bit small but they are easy to manage. I only set up these catalogues on my archive and the catalogues are on the computer it is connected to. Elsewhere lightroom is only used on the understanding it is temporarily and any cataloguing is only temporary, but with the specific condition that an .xmp file is always generated for any activity.
2) .xmp side car files to the rescue
One of the aspects that led me to like Picasa straight away was the ability to cull, rate and keyword photos as I preview them immediately after loading. At that stage I was only shooting jpeg format and this information was immediately incorporated into the embedded EXIF data within the photo. However this embedding only works in jpeg format, not the various RAW format. Thus this extra data the metadata followed the photo wherever it was stored. However in the default lightroom settings this information is stored in the central catalogue, if the photos is moved or copied by any program or utility other than light room this information will not follow the photo. There is however a mechanism in the Adobe photo management philosophy that can store this information for each photograph separately. Instead of including it in the EXIF data embedded in the photo itself it creates a separate small file, with the extension .xmp (for Extensible Metadata Platform). This is actually an old fashioned feature, probably with origins in the Adobe bridge software. It means you must copy two files, the original photo and the matching xmp file together. Finding the way to write this magic XMP file, is not immediately obvious in the lightroom menus. It can not be found under the more logical metadata menu, rather it is somewhat buried under the Edit/Preferences and select the General Tab and the press the Go To Catalogue Settings button on the bottom right. Finally select the metadata Tab on the far right and tick the third item Automatically write changes to XMP.
Whilst Picasa does use XMP style metadata for its facial recognition face tags, it cannot read or write a standard metadata as separate adobe xmp files. However both OnOne’s Perfect Photo suite 9 and Corel’s Aftershot Pro can read and write the metadata into and from .xmp files, since both of these have browse modes I can also easily to the rating and keywords as a preview photos and this will find its way with the photos, wherever they are and even be loaded into lightroom when it imports of photos of my archive catalogue.