Smart previews can generate smaller -- significantly smaller -- preview files on one drive even while your full image files reside on a separate drive. Whatever changes are made to the small version are automatically synced up with the original file the next time your system is connected to that external drive -- without the user having to initiate a sync.
There are a few dozen other changes, such as support for PNG files, true full-screen photo viewing mode by hitting the F key, saving customized book-page layouts and adding videos to slideshows.
Not sure whether Lightroom 5 is worth the upgrade? It's not as clear-cut a decision as was moving to Lightroom 4, when the software made a major leap in functionality.
Download the beta (no earlier Lightroom version or license is needed) and see whether you use the new features enough to justify the upgrade. The free beta will work through June 30. Adobe has not yet released pricing information for Lightroom 5.
If you're not a Lightroom user and aren't happy with the way you currently organize and edit photos, I'd suggest giving this version a try: It's a great chance to use Lightroom free to see if it meets your needs.
Sharon Machlis is online managing editor at Computerworld. Her e-mail address is firstname.lastname@example.org. You can follow her on Twitter @sharon000, on Facebook, on Google+ or by subscribing to her RSS feeds:articles | blogs.
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