GIMP also does not include built-in Raw processing. Photographers will need to download a separate converter, with UFRaw being the most popular. At one point UFRaw was implemented as a plug-in, but the current version is a standalone application that can launch GIMP with the processed image. Fortunately, UFRaw is a very competent Raw converter, with flexible options for setting White Balance and various demosaicing algorithms. It is also frequently updated to support new camera models as they hit the market. It even has the advanced capabilities of Adobe Camera Raw for creating camera-model and lens-specific profiles, and for doing mild pre-processing on the Raw file, but it requires some patience to figure out how to use those more advanced capabilities. Just to set expectations, while GIMP has many of the features of Photoshop, and in many ways a similar UI, you’ll be disappointed if you think you can simply fire it up and act like you’re running Photoshop. You’ll need to meet it half way. One example of this is shortcut keys. For whatever reason, Gimp’s hotkeys are often different from Photoshop. Fortunately there are scripts that will help you quickly remap them to be more similar. Likewise, GIMP will not run your Photoshop plug-ins, and probably never will. It does, however, have its own library of plug-ins. To make life easier for Windows users of GIMP, there is even a tool that provides a graphical UI for choosing and downloading plug-ins. Available plug-ins include many of the functions you might otherwise be missing from Photoshop — like fancy layer effects for your type, and built-in HDR processing, for example. For those who want a platform to experiment with image processing, GIMP is pretty amazing. Scripts can be written in Scheme — like the Script-fu collection pictured at right — or Perl, Python or TCL. The result is a huge collection of open-sourced extensions you can either run as-is or modify to meet your own image processing requirements. As you might expect for open-source software, GIMP’s documentation and help system are not as well developed as those for Photoshop. Fortunately, there is finally a really good book that will get you started: GIMP for Photographers by Klaus Goelker. I have some quibbles with some of the finer points he makes about image editing workflow but it is a thorough — nearly 400 page — overview of both GIMP and related Raw processing options. Fortunately, it is easy enough to try GIMP and decide if you like it. Simply download it and get started. If you’re willing to put up with a bit of a learning curve — and figuring out the GIMP way to accomplish the tasks you do from memory in Photoshop — I suspect you’ll find that GIMP has become a worthy alternative to Photoshop for anyone on a budget who doesn’t need all of Photoshop’s vast feature set. If you’re not satisfied that it comes close enough to Photoshop, then be sure to read our results when we did a similar comparison using Adobe’s own Photoshop Elements. Source.