Adobe Photoshop Camera Raw 4.1 for Photoshop CS3 is now available for download (Mac | Win) from Adobe.com. In addition to supporting 13 new cameras, this release brings welcome improvements to sharpening and noise reduction. Jeff Schewe has posted a great & highly detailed overview of what’s new. If you want the cheap n’ cheerful overview, here’s what the Read Me* file has to say:
New Control available in the Basic panel. Clarity adds depth to an image by increasing local contrast. When using this setting, it is best to zoom in to 100% or greater. To maximize the effect, increase the setting until you see halos near the edge details of the image, and then reduce the setting slightly.
Additional controls available in the Detail panel. The zoom level must be set to 100% or greater in order to view the effects of these controls.
Adjusts edge definition. Increase the Amount value to increase sharpening. A value of zero turns off sharpening. In general, set Amount to a lower value for cleaner images. The adjustment locates pixels that differ from surrounding pixels based on the threshold you specify and increases the pixels’ contrast by the amount you specify. Press Alt (Windows) or Option (Mac OS) while dragging this slider to view the sharpening on a grayscale preview.
Adjusts the size of the details that sharpening is applied to. Photos with very fine details may need a lower radius setting. Photos with larger details may be able to use a larger radius. Using too large a radius will generally result in unnatural looking results. Press Alt (Windows) or Option (Mac OS) while dragging this slider to preview the radius effect on edge definition.
Adjusts how much high-frequency information is sharpened in the image and how much the sharpening process emphasizes edges. Lower settings primarily sharpen edges to remove blurring. Higher values are useful for making the textures in the image more pronounced.
Controls an edge mask. With a setting of zero, everything in the image receives the same amount of sharpening. With a setting of 100, sharpening is mostly restricted to those areas near the strongest edges. Press Alt (Windows) or Option (Mac OS) while dragging this slider to see the areas to be sharpened (white) versus the areas masked out (black).
* Hah–I will get someone to read the contents of a Read Me! (Talk about an ironic name. Those things are like reader-repellents.)