Adobe Camera Raw (ACR) isn’t a stand-alone app, but rather an add-on built into Adobe Photoshop and Photoshop Elements. Despite its add-on status, ACR offers a rich set of features for tweaking raw files. You can easily adjust exposure, make lens corrections, fix white balance, and do some basic image editing. When you click “done,” Camera Raw creates an XMP file (also known as a “sidecar file”) that reflects the changes you made nondestructively; the actual raw file hasn’t been altered. However, once loaded into Photoshop, any changes made are destructive, and you can’t save the file as a raw file—not even a DNG-variant raw file.
Adobe Camera Raw is the conduit by which raw images are imported into Adobe's photo editors, but it's also a useful application in its own right.
While ACR offers settings for both luminance and color-noise reduction, their overall impact can be hard to discern. ACR’s noise reduction certainly isn’t in the same class as Bibble’s Noise Ninja. And since ACR is itself an add-on, it doesn’t have its own set of aftermarket filters. Indeed, at its heart, ACR is really just a one-dimensional app for modifying the specific properties intrinsic to raw files. It’s got some limited image-editing tools—like crop and straighten—but its real strength lies in easily adjusting basic photographic attributes, like exposure and white balance. Its feature set is limited.
The user interface is a bit confusing, and it takes awhile to realize that the icons atop the adjustment panel are actually tabs that take you to other panels. Also, you can’t have multiple panels open at once. Performance-wise, ACR is pretty damn speedy: Version 5.6 converted 100 12-megapixel Nikon raw files in just two minutes, 56 seconds. Our CPU meter always ran with all threads, though the bars surged and dropped to zero repeatedly.
The inability to run ACR as a stand-alone app makes it an odd duck. At a minimum, you need to buy a copy of Photoshop Elements in order to even play with ACR. To this extent, if you want ACR’s functionality, but don’t want a version of Photoshop, you’d do better to invest in Adobe Lightroom.