The arrival of the first version of Adobe Lightroom a little over a year ago was a game-changing moment for photo editing on the PC. It offered non-destructive editing of JPEGs and camera RAW files plus powerful organisational and tagging tools, all wrapped up in a beautiful user interface that invited almost equal amounts of straightforward experimentation and efficiency. Since our first review of Lightroom 1, the product has undergone a few updates - most obviously the jump to version 1.4 a few months ago, but Lightroom 2 is the first update Adobe is charging for.

Adobe hasn’t fiddled too much with the first version’s successful presentation. The monochromatic style remains, as do the five workflow modules of Library, Develop, Slideshow, Print and Web: each one representing a step on the path of an image from camera to paper.

There have been key changes made at every step, though. Library mode improves they way images are catalogued, searched and presented. Previous versions of Lightroom made little distinction between images held on a local hard disk and those held on an external or networked storage device.

The new volume management feature corrects this, and now each image-storing disk in the Lightroom catalogue is represented and colour-coded to give information: green means the disk is online, orange means the disk is online and approaching capacity, while red means online and full.

You can also get at-a-glance information about the drive — its capacity versus the space used, for instance, or the total number of images held on the disk. Usefully, even if a disk is offline, the latest information about it is retained, as are the previews of the images on it, so you can still tell where pictures are stored.

Searching for images is one of Lightroom 2’s most-improved features. Filtering has been updated: it’s now possible to filter images with up to eight filters. This allows you to be very specific when it comes to finding files. You could, for instance, filter files based on the date the image was taken, then by camera type, lens, shutter speed, aperture, ISO, flash state and file type. It all makes finding the files you’re after supremely easy.

Indeed, the only thing better than the customisable filters is Lightroom’s new Smart Collections. These allow you to set an almost unlimited number of filters (we reached 65 filters before we stopped counting) along the same lines. Then, each time an image is added which meets the criteria, it’s automatically added to the Smart Collection. If you methodically tag your images as you import them, Smart Collections makes keeping track of certain kinds of shots, or different subjects, incredibly easy.

Another significant change is support for multiple monitors. If you have a couple of monitors on your desk, Lightroom can now extend its layout over both. One monitor shows a library view, while the other shows the standard Lightroom view. The upshot is that you can keep an overview of your image catalogue while working on an image.

The Develop module has undergone some improvements. The first version of Lightroom was a wholesale image editor, in that most of the changes you could make to an image were universal, such as curves adjustment, vignetting or exposure shifts.

Lightroom 2 introduces localised editing, allowing you to dodge and burn your images as you would in Photoshop. Lightroom 2 also introduces gradient masks. These mimic the effect of a graduated neutral density filter and are particularly useful for landscape images. The tools of the previous version remain, of course, including the well-implemented spot healing tool.

Adobe has also introduced new tools for images on their way out of Lightroom. The Export tool has a built-in sharpening filter, offering presets that sharpen the imgage either for print or for the screen. The Print module has also undergone surgery and now allows you to generate a contact sheet for your prints. Usefully, this can ‘print’ to a JPEG file as well as a standard printer, so that you can prepare a contact sheet for a professional printer.

The drawbacks are few and far between. The version of Lightroom 2 we reviewed definitely ran slower than its predecessor: with exactly the same catalog Lightroom 2 was sluggish compared to its forebear. For the first time, however, Lightroom is compatible with the 64-bit versions of Windows Vista and Mac OS X, which theoretically means improved performance on systems with more than 3GB of RAM.

If you don’t already have Lightroom, version 2 is a great place to start. Its feature list has been usefully padded out, and if you aren’t already aware of the joys of non-destructive JPEG editing on Windows, Lightroom will have you hooked.

If you’re a current user of version 1 the case for upgrading is initially less compelling, but we found that the enhanced filtering and organisational tools and improved per-pixel editing tools grew on us over time: eventually, when we did go back to Lightroom 1.4 we found ourselves at a loss without them.