The Raw Format

One of the most troublesome issues about "raw format" is that there is no such thing. While "JPEG format" refers to a particular, published file specification, there is no widely accepted standard for the formatting of raw camera data. Instead, each camera manufacturer creates its own raw file format. So when you shoot raw with a Canon camera, you get .CRW or .CR2 files. When you shoot raw with a Nikon camera, you get .NEF files, Olympus cameras produce .ORF files, and so on (Figure 4.3).

Figure 4.3. Because every camera maker insists on creating its own type of custom raw file, there is no single raw format or specification as there is for JPEG, TIFF or Photoshop files.

Because there's no single accepted, standardized format, and because manufacturers don't always publish the details of their specific formats, application developers have to do a lot of work to figure out how to support raw files from a particular camera. In addition, in some cases a maker's raw format can change from camera to camera. Most raw software developers are diligent about releasing upgrades that support new cameras, but these upgrades can take time to come to market.

A lot of people are concerned about this "corporate ownership" of the various raw formats. They worry that, years from now, if any of these companies go out of business, the details of their raw files could disappear, leaving us all with gobs of raw images and no specifications for how to read them.

Adobe Digital Negative Specification

To address the lack of an open raw standard, Adobe has created the Digital Negative Specification, sometimes referred tomysteriouslyas DNG. The Digital Negative Specification is a completely open formatAdobe has published all of the details of the specso even if Adobe one day goes out of business, the standard can continue to be supported and developed.

In addition to providing a single open standard for formatting raw camera data, the DNG spec includes the ability to store special "private" data that only the camera manufacturer knows how to access. In this way, camera makers can continue to include raw features that can be accessed only by their own special software, allowing them to differentiate themselves from other makers (ideally, though, they'll stick to the open part of the DNG format). In theory, everyone wins with DNG. Camera makers get a robust spec that addresses all of their concerns, and end users get an open standard, which ensures that they'll always have access to their images.

At the time of this writing, no manufacturers have built DNG support into their cameras. However, Adobe provides a free DNG Converter application that you can download from www.adobe.com/products/dng. This application can read any of the raw formats currently supported by the Camera Raw software. With it, you can convert your current proprietary raw files to Adobe's open DNG files, ensuring that your raw data will exist in a form that will most likely always be readable (Figure 4.4).

Figure 4.4. Adobe's DNG converter allows you to convert the proprietary raw images from your camera into Adobe's DNG format, an open format that anyone can use.

In Chapter 5, we'll discuss how to work DNG support into your raw workflow.

Why you should use Camera Raw

Despite the myriad high-quality camera raw conversion apps available, you will probably find that Camera Raw is your best option in terms of quality, price, workflow, and feature set. Camera Raw was originally released as a plug-in for Photoshop 7. Adobe no longer sells a stand-alone version of Camera RawAdobe wants you to upgrade your copy of Photoshopbut Camera Raw is built in to Photoshop Elements 3 and 4 and Photoshop CS and CS2.

Camera Raw sports a clean, extremely functional interface that's easy for novice users to negotiate, but also offers all of the controls that power users expect. In addition to its full support of all of the basic raw processing features that you need for day-to-day work, Camera Raw includes important extra features, such as controls for eliminating vignetting and chromatic aberration. One of Camera Raw's most impressive extras is its highlight recovery capability, which you'll learn more about in Chapter 6.

In addition to its features and quality, Camera Raw scores over its competition simply because it's integrated into Photoshop. If you're going to be using Photoshop for your image editing anyway, why hassle with the expense and workflow complication of an external raw converter? With Photoshop/Camera Raw, you get a raw converter plus all of the other retouching tools that you're already used to in one package. Finally, Adobe has done an excellent job of building a smooth workflow around Camera Raw, making it simple to process individual images or huge batches.

Camera Raw compatibility

To find out if the latest Camera Raw is compatible with your camera, take a look at www.adobe.com/products/photoshop/cameraraw.html. There, you will find a list of currently supported cameras. Elements and Photoshop CS2 present slightly different versions of the Camera Raw dialog box, simply because Elements 3 doesn't support all of the features that CS2 does. We'll go over these differences later in this chapter. Some of the differences are higher-end features that we won't be covering in this book.

If you're using Photoshop 7 or CS, then you can't run the latest version of Camera Raw. However, previous versions use an interface that is almost identical to version 3.1's. What's more, the underlying concepts and workflow, as well as Camera Raw's fundamental image processing tools, are the same in the earlier versions, so you should be fine with this book. If you find yourself confused by any of the interface differences shown here, you should be able to clear things up with a quick look at Photoshop's built-in Help facility.

If you've chosen a different raw converter, you'll probably find that almost all of the concepts in this book still apply, except for the features that are specific to Camera Raw. Obviously, your program's interface will vary.