Lightroom uses the concept of Shoots as named directories within the Library. A Shoot can contain files from a number of different places and times, on any drive attached to the computer. But files can also be placed into Collections -- essentially ad-hoc groupings of files. When you import files into Lightroom, you can add your copyright information and keywords as IPTC metadata. Keywords automatically register in the program's Keyword Search function, enabling you to find any files in the library containing those words with a single mouse click. You can designate these as a Collection, creating a new grouping of files. But the Collection is virtual -- just a database entry. It takes up no additional disk space yet is instantly accessible.
Module number two, called Develop, is for adjusting and manipulating individual images. Unlike any other programs except Apple's Aperture, Lightroom handles both RAW files and other formats -- JPEG, TIFF, and Photoshop's own PSD -- in virtually the same way, using the same tools and adjustments. This transparent approach differs from the workflow in Photoshop, which requires you to first process and convert RAW files in Adobe Camera Raw. And since Lightroom's RAW processing engine is based closely on Camera Raw itself, it supports the RAW formats of nearly all digital cameras ever produced. It also includes all the tools we're used to seeing in Camera Raw, but organizes them better.
One of the Develop module's biggest advantages is that it lets you adjust color, sharpness, white balance, and other settings without altering the original file. Most RAW processing programs provide this capability, since it's intrinsic to the format, but only Lightroom and Aperture do so with other file types, including JPEG, TIFF, and PSD, in the same way as RAW. The program does so by creating a metadata instruction list (a "recipe" of settings) rather than altering actual pixels. This conveniently eliminates proliferation of multiple versions and saves space on your hard drive.
Develop adds some terrific features not available in Camera Raw. The Grayscale Mixer affords much more control over converting color images to monochrome, allowing you to individually adjust any or all of the six primary and secondary colors while preserving overall luminance values. Split Toning lets you apply separate tints to highlight and shadow areas in both black-and-white and color images. With the Presets Browser you can apply a variety of ready-made and custom settings to your photos. Also noteworthy is the Quick Develop feature, which offers a simplified set of adjustment tools for batch-processing multiple images.
Slideshow, the third Module in Lightroom, contains an array of tools for preparing and displaying on-screen presentations. A finished show can be saved as a PDF file (Adobe Acrobat format), a Flash animation, or a Web-ready HTML page. You can select a group of images for a slide show from a Shoot or Collection, or choose individual shots from the thumbnail picture browser.
The fourth module in Lightroom is Print, which easily surpasses the printing options found in most other general-purpose imaging programs. What's special about the Print Module is that, unlike Photoshop, it's designed to handle images in groups, not one at a time. To print a series of individual photos, all with the same page layout, simply add them to a Quick Collection (an ad-hoc grouping of files) and the pages will automatically queue up for printing. You can also print an entire Shoot or Collection (or any group of multiple shots) as contact sheets. Lightroom's Template Browser gives you preset printing layouts for both single and multi-image pages, and you can create and save custom layouts of your own.
The Lightroom beta is very much a work in progress, and Adobe doesn't know which features will ultimately be incorporated. But the final product is sure to reflect the opinions of photographers like you and me.