Adobe Photoshop Lightroom is built atop a database architecture that relies on a centralized catalog to house information about your still images and video files.

One of the most common questions I'm asked about Adobe Photoshop Lightroom from new (and sometimes not so new) users is, 'Why do you have to import photos to the catalog first before you are able to edit them?' The answer to this question goes right to the heart of Lightroom's approach to information storage and retrieval, which to my mind more adequately addresses the needs of today's photographer. In this article I'll lay out the basic principles of image management in Lightroom and explain how this approach can actually make the task of locating your images more efficient.

Image browser vs. database manager

As computer users who've come of age during the PC revolution, we have grown accustomed to the idea that everything needs to be sorted into folders, and indeed folder hierarchies have become the primary means of organization. This file directory management approach may make sense with task-specific Word documents but becomes extremely limiting when applied to large collections of less easily-defined images. Yet this is exactly how image browser software, like Adobe Bridge operate. For all their admittedly useful features, they simply browse the existing folder structure on your hard drive.

And my chief complaint about sorting images by folders is the very real problem of determining just which folder they should go in. Someone once told me about an underwater photographer who maintained a small photo library of his work. When adding new transparencies, he would have dupes made so that a photograph of say, a diver with a shark could be filed in one set of physical folders labeled ‘sharks’, another named ‘divers’ and another broken down by ‘location’. This physical duplication was necessary in order to make the library system work effectively, but no one would call it efficient. Yet there are people who work this way with digital files precisely because they are not using a database-driven management system.

Here is an example of an underwater photo (in this instance a photo shot by Jeff Schewe). It makes sense to categorize this by the location it was shot in, the presence of a diver, as well as the coral featured in the foreground. In the folder-based example I mentioned above this could involve duplicating the master image several times. Using digital asset management software such as Phase One Media Pro or Lightroom, however, there is no need to create physical duplicates.

I can't count the number of times I have sat through a seminar where the instructor has come unstuck when relying on folder/browser navigation to locate their demo files. Meanwhile, the audience waits impatiently while the instructor sifts through a complex hierarchy structure of folders known only to himself. Sound familiar?

Database management programs designed specifically for photographs were developed to tame such chaos. One of the first and most well-known was iView Media Pro. The company behind it was acquired, first by Microsoft which renamed it Expression Media, but is now developed by Phase One and sold as Phase One Media Pro. Extensis Portfolio was another option available, but it was the launch in 2005 of Aperture from Apple that showed how one could combine the power of a database with image editing tools to provide an all-in-one solution for photographers. Adobe's entry, in the form of Lightroom, launched soon after.

Point a browser-based app like Adobe Bridge (shown here) at a folder on your hard drive and you'll see everything that’s on the computer. By contrast, the Lightroom Import dialog, pointed at the same folder, only shows the three JPEGs files located there.

What all these database-driven apps have in common is that you have to explicitly import media files into the program, adding them to an app-specific catalog, which is the primary holder of all your image data. This process, while it may seem an unnecessary step, is required in order to build a catalog of files made up exclusively of the images and videos you have deemed relevant. One under-appreciated aspect of the import process is that when you select a directory containing many different types of data, i.e., music files, spreadsheets or Word documents, the software filters out any file formats it does not support. This can work to your advantage as you only see the files you'd actually consider working with and don't have to bother wading through irrelevant files.

Metadata: Your new best friend

Instead of relying on a folder structure to sort your images you can manage your photos much more effectively by using keyword and EXIF metadata. Metadata - literally data about your data - is vital to managing any collection of digital files. In fact, placing an image inside a descriptively named folder amounts to a very rudimentary type of metadata; an identifier that can be used to help locate the data stored in that folder.


Keywording is a very robust form of user-generated metadata that allows you to apply multiple descriptive tags to an individual file. Let’s return to the underwater photographer example I mentioned earlier. This guy could choose to replicate his film library system by placing duplicate image files in multiple folders that could be read by a file browser. With a database-driven cataloging program, however, he would only need to import one master image and then use the cataloging software to append multiple keyword metadata tags to identify the image. With a program like Lightroom it is fairly easy to create varied collections of photos in which multiple instances of a single master photo appear in more than one collection. No files are duplicated on your hard drive. The single master image is simply referenced multiple times by the catalog. Edit that master image later on, say by converting it from color to BW, and the new version is automatically propagated in every collection. That's about as close to a free lunch as you'll get.

Here is a photo of a male model I shot in Italy. My Lightroom catalog contains only a single master file but the image belongs to five separate collections (virtual folders). You can't do this in a folder-based management system without creating duplicates, or at least aliases, of the original digital file.

Crucially, once you start getting into the habit of tagging your photos with metadata, it then becomes easier to find them. Imagine trying to locate an image on someone else’s computer using a folder browsing method only. You could start by looking inside the My Pictures folder, but where would you look next? For that matter how successful are you at navigating your own Pictures folder? We have all struggled at times to locate a specific file that we know is on the computer system somewhere.

An extensive keyword list makes it very easy to filter the Lightroom grid to show specific images grouped together, even if their master files reside in separate folders or even hard drives. As an alternative to scrolling down a long list of keywords, Lightroom offers a search box (shown in red). As you type, Lightroom automatically filters the list to include potential keyword matches.

With keywording the task becomes simple. If you know how to do a Google search you already know how to search by metadata. In my opinion, this is where the database/catalog method of managing your image library makes your life much easier.

This photograph of a pagoda building was photographed in Victoria Park, close to the London Olympic Stadium (My, how this park has changed prior to the Olympics coming to town!)
Looking at the Keywording panel in Lightroom you can see a list of all the keyword metadata that I manually added to the above photo. The more keywords you add to individual photos, the easier it will be to retrieve them when carrying out a photo search.

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