I have been working on a comparison of Adobe’s Photoshop Lightroom and Apple’s Aperture for Macworld , and I ran into an issue with both programs when I tried to import Raw image files that had been previously edited with Adobe Bridge CS2 and Camera Raw. I wanted to import them with my edits intact—mostly crop and exposure adjustments—but initially both Lightroom and Aperture only imported the original Raw file, without any of the work I had done.
This is because the edits—and this includes adding or editing such metadata as keywords, captions and other tags—are not made to the Raw file directly, but are stored, either in Camera Raw’s internal database, or in a companion file called a “sidecar.” This file resides in the same folder as your image, with the same name and a .XMP extension instead of the Raw format extension (.CR2, in my case). After a bit of tweaking, however, I found solutions for both Lightroom and Aperture that might save you some time if you’re in the same boat.
Making Lightroom happyif
You can create the sidecar files, however; the first thing you need to do is change Camera Raw’s preferences to “Save image settings in sidecar .xmp files” (see screen shot, below).
Then, use Bridge’s Batch Rename feature (Tools - > Batch Rename) on any files you want to import into Lightroom (see below). You don't even need to actually change the name of the files. You can tell Bridge to rename the file to the same name it previously had, but this process will force Camera Raw to write a sidecar file for every image renamed. The side benefit is that it will also contain any edits you performed on the original Raw file.
Importing into Aperture
You can then select all of your imported images in Aperture and use the AutoStack feature to keep the two versions together, which is possible because both the Raw and the Photoshop/TIFF versions will have the same capture time. You can also use the Lift & Stamp tool to copy any keywords or other metadata to your original Raw files, since that data is saved with the exported files. It’s not the best solution, but it at least preserves both versions of your images in your library, and lets you get back to the original Raw image if you want to make a different set of edits.
It’s worth noting that both Aperture and Lightroom import most Raw files without any issues at all; you really only need these solutions for those photos you edited with Camera Raw and want to keep a version of your edited file. Both applications will preserve the original file intact and untouched.
[Updated April 6, 1:20 p.m., to clarify Raw conversion differences between Apple and Adobe, and to note that editing also refers to metadata.]