I’ve often been frustrated with the lack of a good solution for syncing a photo library amongst multiple computers.  Typically, I only have my laptop with me when I take photos, especially on a trip.  When I get back home, I want to sort and edit on a grown-up computer.  None of the photo management tools seem to have any kind of support for this: Lightroom, Aperture, Bridge, etc. all seem to be designed for single computer usage.  Bridge has some allowance for using Adobe’s versioning stuff, but it seemed fairly complex to set up, and it wasn’t clear if it could do what I wanted anyway.

I recently became a fan of Dropbox; it’s fantastic for file sharing and syncing amongst a bunch of computers and phones.  (If you decide to try it out, use this referral link so that I get some extra space!)  I started wondering if I could use Dropbox to sync the Lightroom catalog.  This blog is a set of instructions on how to do just that, and also how to set up your photos so that you can easily migrate them between computers, or keep a backup on one or more hard drives.

Moving your Lightroom catalog to Dropbox

This one’s pretty simple.  First, install the latest version of Dropbox 0.8 from their beta forums.  0.8 has one feature that makes this much easier and useful — you can set it to ignore a set of folders for syncing.  This will become important in a second.

After you have Dropbox installed, simply take your main Lightroom catalog file (or multiple ones, these instructions work equally well for multiple catalogs) to somewhere inside your Dropbox folder.  I have a Lightroom folder inside Dropbox that has all my catalogs.

Open the catalog you just moved; Lightroom should start up, and all your data will be there.  However, if you go back to your Dropbox folder, you’ll see that Lightroom created another folder to store previews alongside your catalog.  For example, if your catalog is called “Lightroom 3 Catalog”, you should see “Lightroom 3 Catalog Previews.lrdata”.  This is the folder that we don’t want sync’d — it can get quite large, and there’s no reason to synchronize it.  Open Dropbox preferences (on Windows, this will be from the Dropbox icon in your system tray; I’m not sure how to do it on Mac), select Advanced, and click on Selective Sync.  Navigate to where your catalog is, and uncheck the Preview folder.

And that’s it.  Your other computers should have gotten a copy of your catalog, and you can open them there and work from the same set of data.  However, note that only one computer can have the catalog open at a time.  Lightroom creates a lock file which gets sync’d, but you can run into problems if you modify the catalog from two different computers while they’re both disconnected.  If you get into this state, you’ll have to do some merging of data just as if you had two independent catalogs.  Just get into the habit of closing Lightroom when you’re done with it on any computer and you’ll be fine.  (Or, if you’re disconnected for a while with a laptop, only use Lightroom there and connect it to the network before opening up the catalog on any other computers.)

However, this doesn’t get your photos to those other computers.  Ideally, you want Lightroom to not care what computer it’s on.

Making your photos available to multiple computers

Note: this section is written with Windows users in mind.  If you’re a Mac user, you can do the same thing via symlinks, but I don’t have detailed instructions here.

You can do this by making sure that the photos are always in the same location, no matter what computer you’re on.  The simplest way is to make sure they’re always in the same place — for example, “C:\Photos”.  That becomes somewhat inflexible, though.  For example, you may want to keep all your photos on a large external hard drive, but only keep a local cache of your most recent work to save disk space.

Enter the subst Windows utility.  subst lets you assign a drive letter to any location on any drive, and modify the location it points to at will.  For example, typing “subst p: d:\storage\photos” in the command prompt will make the P: drive show the contents of D:\Storage\Photos.  Not a fan of the command prompt?  You may want to use Visual Subst, which provides a nice interface to the same functionality.

With this, you can tell Lightroom that all your photos are under P:\.  Create a P: drive that points to where you have your photos stored.  Then, open Lightroom, and under Folders on the left side, right click on each folder and select “Update Folder Location”.  Navigate to the same folder under P:\, and select OK.

Now, copy all your photo folders to a portable drive.  Take that drive to another computer, plug it in, use subst to set up your P:\ drive, and open Lightroom — it should see your photos, oblivious to the fact that it’s on a different computer and getting the photos from a portable drive!

You can change the P:\ mapping at will.  For example, I keep my photos sorted by date, with the top level folder being the year.  My laptop only has the contents of the 2010 folder.  Any earlier ones are backed up on the drive (and in other places).  In Lightroom, these other folders show up grayed out with a little ? next to them.  If I need to do something with these, I plug in the external drive, change where P: points to, restart Lightroom, and I’m back in business.

Actually synchronizing your photo collection

Now that you have the import and edit photos using the same catalog anywhere, you need a good solution for actually keeping the photo folder contents up to date, and making sure new changes make it to your various backups.

Unfortunately, I don’t have good instructions for this, especially on Windows.  On a Mac, you can use rsync, and there’s likely a nice UI for it somewhere  On Windows, you’d want to use rsync as well, but I’ve yet to find a version of rsync that seems to work well.  Unison is also an option, but I’ve had problems with it as well.  Right now I do a somewhat manual job of keeping these photos up to date.  Usually it’s not difficult, because I just add photos (so it involves copying a few new by-date folders over), but it gets complicated if I do any edits in Photoshop.

If I come up with a good solution here, I’ll update this post in the future.

Wrap-up

That’s it!  Enjoy having your Lightroom catalog available everywhere and not being tied to one computer for editing your photos.