How Lightroom works: Where it keeps your images and presets, and how to back up

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Lots of people are leaping onto the Adobe Photoshop Lightroom bandwagon. One reason is licensing and pricing—for $150 you get a stand-alone copy with a perpetual license or you can subscribe to it, along with Photoshop, for a slick $10/month. Another reason for Lightroom’s popularity is that it’s a superb alternative to the soon-to-be-dead Aperture.

While Lightroom is light years easier to use than most editors, it works in a unique way and, as such, has several pieces and parts. This begs (legitimate) questions such as, “Where are my pictures?”, not to mention “Where are my presets?”, and everyone’s favorite, “Which files do I back up?” In this column, you’ll learn all that and more.

Where does Lightroom store my images?

The short answer is that it doesn’t. Unlike Photoshop and its image browsing companion, Adobe Bridge, Lightroom is a database (other databases you might know are iPhoto, the new Photos, the Photoshop Elements Organizer, and FileMaker Pro). Lightroom doesn’t store your images, it stores information about your images in a catalog that contains a record for each image you tell it about (technically speaking, the catalog is the database).

Each record includes a smorgasbord of image info, including where it lives on your drive, camera settings at capture, any descriptions, keywords, star ratings, flags, or labels you’ve applied in Lightroom’s Library module, and every edit you’ve ever made in the Develop module. (If you’re using Lightroom Mobile on an iOS device, you’re editing previews of the images referenced by the Lightroom catalog back on your desktop Mac.)

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As this infographic illustrates, your Lightroom experience consists of four parts: your images, the Lightroom application, catalog(s) containing records that point to your images, and a presets folder.

This segregation of image files from editing info means you can undo anything you do to an image in Lightroom anytime you want. This setup also lets you store images wherever you want: in your Pictures folder or in a custom folder structure (say, by date or event) on an internal or external drive, or network server. You can also control where your Lightroom catalog lives, though you can’t put it on a server; catalogs must reside on local drives attached to your Mac. For the speediest Lightroom experience, store your catalog(s) on your fastest drive—say, a solid-state (SSD) or hybrid (part SSD, part traditional spinning platter drive).

Once you’ve told Lightroom about your images using its Import command, don’t move, rename, or delete them behind its back (say, using your Mac’s Finder). If you do, Lightroom won’t be able to find them (though you can relink images if you forget). It’s best to reserve such file management chores for the Folder panel in Lightroom’s Library module so it can update image records as you go. By the way, when you delete an image in Lightroom, the app asks whether you want to delete it from the catalog, which only deletes its record, or if you want to delete it from your hard drive, which moves the image to your Mac’s Trash.

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As you can see, deleting a file from Lightroom doesn’t necessarily mean it’s deleted from your drive.

There’s no limit to how many image records a Lightroom catalog can contain. You can also create multiple catalogs and easily switch between them, though such organizational overachievement comes at a modest price: You can only open one catalog at a time, and Lightroom’s filtering and search tools can’t see records in a catalog that isn’t open. So if you create a separate catalog for your professional work and another for personal photos, you’ll need to remember which catalog contains the records for the images you want to find.

Where do my presets live?

One of Lightroom’s many advantages is that you can create a preset for just about anything—file name conventions, copyright info, anything you do in the Develop module, export settings (more on that in a minute), watermarks (both graphic and text-based), slideshow and web gallery settings, photo book page layouts, and more. You can even determine when certain presets are applied—on import or export.

Exporting an image from Lightroom prompts the program to create a copy of the original, with or without your edits applied, at the size and file format you specify, with or without a watermark, copyright info, and so on. As the infographic above shows, Lightroom presets are stored in a completely separate folder (you can control its location, too).

Backing up your files

When it comes to backing up your Lightroom Life, you have to back up all the pieces and parts mentioned above: your original images (wherever they live), your Lightroom catalog, and your Lightroom presets folder. Arguably, you should back up the Lightroom application, too, though you could re-download it from Adobe’s site.

Ever the helpful one, Lightroom prompts you to back up your catalog each time you quit the program, and you can pick where the duplicate is stored. Since your catalog contains only instructions and not actual images, it doesn’t take long to copy.

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The Choose button lets you pick where your backup catalog is stored. If possible, store it on a different drive than your original.

Now that you understand where Lightroom stores your stuff, you can put your focus back where it belongs—editing your images. Until next time, may the creative force be with you all!

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