Both digital cameras and iPhoto have been around long enough that few long-time Mac users have what you would call an entirely manageable iPhoto library. Their libraries are instead often bloated, full of duplicates, or so ungainly that some have opted to simply create new libraries rather than slogging through an old and slow one. Apple has made little provision for these issues: Unlike with iTunes, iPhoto has no Find Duplicates command; and although you can create a new library by holding down the Option key while launching iPhoto and clicking Create New, you can’t merge libraries or easily copy images between them.

In Apple’s world, this is considered a “rich third-party opportunity” and, in this case, that opportunity has been seized by Fat Cat Software with its $30 iPhoto Library Manager, an application that allows you to easily create and manage multiple iPhoto libraries, browse the images within multiple libraries, copy images between libraries, locate duplicate images within and across libraries, merge libraries, and rebuild corrupt libraries. We first reviewed iPhoto Library Manager way back in 2006; it's been updated many times since then.

iPhoto Library Manager’s interface is reminiscent of iPhoto—much more so today than when we last looked at the utility. In the toolbar, you find the application’s major commands—Create Library, Add Library, Remove Library, Reveal Library, Quit iPhoto, Find Duplicates, and Merge Libraries. Additionally, you can choose to browse the selected library as thumbnail images or in a list, with the latter providing metadata information such as title, date taken, keywords, place, and rating. (You needn’t launch iPhoto to view this info.) A Search field rounds out the toolbar.

Along the window’s left edge you find an iPhoto Libraries pane that includes any libraries you’ve added. (When you first launch the utility, your current iPhoto library appears here, and it will likely be the only library you initially see.) A Library pane to its right bears entries for recent images, events, albums, Facebook, Flickr, projects, and slideshows. You can instead select the Photos entry to view all the selected library’s images. Select an item in this pane and its contents appear in the large browser pane to the right. This browser lets you zoom in and out on images, much as you can in iPhoto.

The toolbar’s commands are largely self-explanatory. Click Create Library to create a brand-new iPhoto library. As with iPhoto, you can choose to store this library wherever you like. The Add Library command also mimics iPhoto by listing any iPhoto (and Aperture) libraries the utility can find on your Mac. (You can also choose to add a library manually.) To open any added photo library in iPhoto, just double-click on it.

To copy photos between libraries, just select them in one library and drag them to another. iPhoto Library Manager will open the other library in iPhoto and copy the images along with their metadata to that library.

Merging libraries is also quite easy. Click Merge Libraries in the toolbar and an entry of the same name appears in the iPhoto Libraries pane. In the setup area to the right, you add your source libraries and either merge them into an existing library or create a new, empty library as the destination of the new merged library. In the process, iPhoto Library Manager can look for duplicates; the utility lets you choose which of the duplicate images to add to the library—the original unmodified version, for instance, or an edited version. To see what the merged library will look like prior to committing to it, click the Preview button in the top-right corner of the window.

So far, so good. The Find Duplicates feature deserves more attention, however. It works using an algorithm designed by the application’s developer. Once duplicates are identified, you can then filter them using rules similar to rules you might construct in Apple’s Mail. For example, you can select photos by constructing a combination of such conditions as rating, file size, description, modification date, and title. In an actions area you then choose what to do with those images filtered as duplicates—for example, move them to iPhoto’s trash, assign a keyword to them, or move them to a Duplicates library that iPhoto Library Manager creates.

This is very helpful, but in my testing, the algorithm that initially identifies those duplicates is only moderately effective. It’s fast, but it failed to turn up quite a few duplicates I had in one of my libraries. While I’m happy that the feature exists, I’ll continue to use Brattoo Propaganda Software’s $8 Duplicate Annihilator, which can take hours to scan a large library, but produces better results.

Still, that gives us one just-okay feature among many very good ones. Considering that iPhoto Library Manager truly provides the power for those with tens of thousands of images to manage multiple iPhoto libraries, I consider that more than fair.

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