The PowerShot G9 is about as much camera as you need in a small-ish form factor.

Mention “digital photography” and no two people will think of exactly the same thing. For many, it may be an idea as simple as using a point-and-shoot camera to run around taking endless snaps until space on the flash memory card runs out. A quick trip to the computer to offload and they’re back in the game. While some are content with this state of affairs, others are ready to take the next step to greater photographic enlightenment, which isn’t a huge leap. And because experimentation costs you nothing—you can learn about digital photography without the expense of burning through endless rolls of film—today‘s digital cameras make the critical, and highly educational, trial-and-error process much more accessible and enjoyable.

The obvious place to start your photographic journey is with a point-and-shoot camera, and once you dive in and start experimenting with your camera and the myriad image editors available for the Mac, you’ll soon discover that there’s a lot more to digital images than JPEG files. RAW is the mode preferred by pros for the range of options it provides. Most of the cameras that can create RAW image files are DSLRs, however, and they present a whole new set of considerations: a bulkier body, a higher price point, and an often overwhelming universe of add-ons (lenses, flashes, filters, and much more). So, we set out to find compact digicams that can shoot RAW—because the camera you use the most is the one you always carry with you, and shooting RAW is the obvious next step on the path to becoming a better digital photographer.

The RAW and the Cooked
What is RAW format anyway? Why is RAW better than JPEG? It all comes down to the amount of visual info that’s captured—and retained—in the file. When a digital camera takes a picture, its image sensor captures color values for each pixel that it can sense. This raw data is then sent to another chip in the camera that does some image processing, after which a fast hardware JPEG compressor creates the file that lands on the flash card. (In case you were wondering, RAW is not an acronym like JPEG, and there is no standard accepted spelling; for the sake of consistency, we use the all-caps variant.)

JPEG is a lossy image format, which means that it throws away some data during the compression process—and every time you save the image during editing, if you don’t use another format like PSD (Photoshop’s format) or TIFF. This is one count against using JPEG. And each camera also processes the image data before compressing it—as you become more experienced with digital photography, you may not like precisely how the camera performs this processing. In fact, you may prefer do it yourself, which is only possible if your starting point is an unadulterated RAW image. Next, as computers become more powerful and new image-processing options become available, you want the maximum flexibility to reprocess your photos. Finally, for those of us who want maximum fidelity for archived photos, storing RAW files means that you are guaranteed to have the maximum amount of image data that the camera was able to capture and that you lost nothing along the way.

But there are several gotchas with RAW files that aren’t obvious to the uninitiated: RAW images tend to be large—substantially larger than JPEGs—for example, a RAW image taken with the Canon PowerShot SD870 IS after we installed CHDK  weighed in at 9.9MB RAW, compared to 2.9MB as a JPEG, a 71 percent size increase. What’s more, the actual format of RAW files differs from camera to camera. Every camera—not just every camera manufacturer—has a different RAW format. And each format requires explicit software support before it can be read and used. (One exception to this is Adobe’s DNG format, see “DNG! It’s a Digital Negative.”) As it happens, the three cameras we reviewed generate RAW images that can be read directly by the imaging infrastructure built into OS X, meaning that you can view them in Preview without specialized software (for a full list of cameras whose RAW files are directly viewable in Mac OS 10.5, see http://support.apple.com/kb/HT1475).

There’s another gotcha with RAW files, but it’s a little more complicated. The technology used by the vast majority of image sensors in today’s digital cameras is called a Bayer array. This type of sensor has red, green, and blue pixel sensors spread all over its surface, with the individual pixels right next to each other. But because of this proximity, and the shrinking size of the individual pixels, RAW shots taken at high ISO (generally low light conditions) often have a lot of visual noise (static) in them. JPEG images generated by the cameras usually have the camera’s particular noise-reduction applied, and this may not result in a final image that is to your liking. The good news is that there are plenty of tools out there to help reduce the noise after the fact, such as PictureCode’s Noise Ninja ($35–$80 depending on options chosen, www.picturecode.com) or Akvis Noise Buster ($49, akvis.com). Most image-processing apps like Photoshop and GraphicConverter also offer tools that help you reduce noise. If you shoot RAW, you can try out as many of these as you want until you find the solution that gives you the results you’re looking for.