Adobe Photoshop has long been the defacto standard for professional photographers and serious amateurs alike. Adobe recently released Photoshop CS4, and it includes some great new features.

For most users, the best way to make image adjustments in Photoshop is to use layers so that the adjustments are non-destructive. Photoshop CS4 makes that process faster and easier with an “Adjustments” panel containing tools like Curves, Levels, Hue/Saturation, black & white conversion, and the new Vibrance adjustment. Adobe claims that the new Adjustments panel helps eliminate up to 90% of the mouse movements required to make nondestructive image adjustments and I certainly agree that it is a much more efficient way to work.

The new Vibrance adjustment is also a nice addition. Adjusting saturation can be difficult, especially when skin tones are present. I found the Vibrance control allowed me to tweak overall image saturation with a much less impact on skin tones than the traditional saturation control, making it great for portrait work.

Another new feature introduced in CS4 is “Content Aware Scaling.” At some point, most of us have fussed with an image that simply isn’t the right ratio – you know, that tightly cropped 2:3 ratio image from your SLR that looks great at 8×12, but now needs to fit an 8×10 matte. Even if you’re really good at extracting objects from the background, maintaining the aspect ratio of a foreground object while stretching or compressing the background to fit is very difficult. According to Adobe, this new feature analyzes the image while you adjust it and intelligently recomposes the scene to preserve the most visually interesting areas. In practice, when used within reason (for example going from 8×10 to 8×12), I found that it works quite well. However, it’s not magic, and scaling some images will require that you manually mask critical objects.

CS4 also introduces “extended depth of field”, which allows photographers to “shoot the scene with a series of focal points, and use the enhanced Auto-Blend Layers feature to automatically create a new, single image with a depth of field encompassing the entire series.” Other new features include enhancements to aligning and blending features for panoramas, better dodge/burn tools, and improve masking.

But perhaps my favourite change to Photoshop CS4 is tighter integration with Photoshop Lightroom 2. I’m a huge fan of Lightroom, and I’m glad to see them play better together. For example, you can select multiple images in Lightroom and with a single command send them to Photoshop as separate layers, components of a panorama, or to be merged into an HDR image. Photoshop and Lightroom now share the same underlying technology for dealing with RAW images, so adjustments made in either application are now recognized by the other. 64-bit Vista users will also be pleased to know that Photoshop CS4 includes a 64-bit version and it installs automatically on 64-bit systems.