As we've seen, digital cameras produce files in three kinds of formats. JPEG files are the most efficient in terms of use of space and can be stored in various quality levels that depend on the amount of compression you elect to use. You can opt for tiny files that sacrifice detail or larger files that preserve most of the information in your original image.
Some cameras can also save in TIFF format, which, although compressed, discards none of the information in the final image file. However, both JPEG and TIFF files (and RAW files, too, technically) have been processed by the camera before they are created. The settings you have made in your camera in terms of white balance, color, sharpening, and so forth, are all applied to the image. You can make some adjustments to the image later in an image editor, but you are always working with an image that has already been processed, sometimes heavily.
The information captured at the moment of exposure can also be stored in a proprietary, native format designed by your camera's manufacturer. These formats differ from camera to camera, but are called Camera RAW, or just RAW for convenience. You might think of RAW as a generic designation rather than a specific format, just as the trade name Heinz applies to all 57 varieties instead of just one.
A RAW file can also be likened to a digital camera's negative. It contains all the information, stored in 12-bit or 16-bit channels (depending on your camera), with no compression, no sharpening, and no application of any special filters or processing. In essence, a RAW file gives you access to the same information the camera works with in producing a 24-bit JPEG or TIFF file. You can load the RAW file into a viewer or image editor and then apply essentially the same changes there that you might have specified in your camera's picture-taking options.
Of course, to complicate things in the guise of attempting to simplify them, Adobe has introduced a new RAW format called DNG (for Digital Negative), which is offered as a common RAW format that should be compatible with any camera or software. So far, vendors aren't breaking their necks to support it. Another wrinkle is the decision by Nikon to encrypt the white balance data in its RAW files, making it more difficult for utilities from third-party software vendors to interpret all the information in Nikon's NEF files. Fortunately, it took only a few days for independent coders to report they'd "cracked" Nikon's encryption, so it remains to be seen how Nikon's move will affect those who work with NEF RAW files.
Some RAW formats, such as those deployed by Nikon and Canon for their highend cameras, are actually TIFF files with some proprietary extensions. That doesn't mean that an application that can read standard TIFF files can interpret them, unfortunately. Usually, special software is required to manipulate RAW files. If you're lucky, your camera vendor supplies a special RAW processing application that is easy to use and powerful. For example, Nikon offers Nikon View to read and manipulate its .NEF files, and Canon and Minolta both provide viewers for their RAW formats.
If you're not so lucky, you'll get a less capable utility, be asked to pay extra for it, or find that none at all is available. Photoshop CS 2.0 now includes a Camera RAW plug-in (which was formerly an extra-cost option with Photoshop 7) that works quite well. It can be used only with the particular digital cameras that Adobe has elected to support. The list is long, and includes many popular cameras from Nikon, Canon, and Minolta. You'll find that third parties also provide RAW decoders for specific camera models, such as YarcPlus and BreezeBrowser for Canon, and Bibble for the Nikon line. The great freeware Windows utility IrfanView can handle RAW files such as Canon's .CRW format. Mac users can work with programs like Lemke Software's GraphicConverter.
Many digital photographers shoot nothing but RAW images, preferring to do all their image processing later in their computer. Such photographers have several things in common: They're extremely fussy about their images, they have a ton of memory cards and almost unlimited storage space, and they're willing to spend a great deal of time working on their images. Be prepared to spend more time shooting the images, too, because RAW files can take a bit longer to store on your film card than your average JPEG file. (TIFF files can take even longer.)
For most of us, JPEG is fine most of the time. RAW is a good choice for exceptional photographs or exceptional needs (or if you just want to get the highest quality).
Some cameras can also save in TIFF format, which, although compressed, discards none of the information in the final image file. However, both JPEG and TIFF files (and RAW files, too, technically) have been processed by the camera before they are created. The settings you have made in your camera in terms of white balance, color, sharpening, and so forth, are all applied to the image. You can make some adjustments to the image later in an image editor, but you are always working with an image that has already been processed, sometimes heavily.
The information captured at the moment of exposure can also be stored in a proprietary, native format designed by your camera's manufacturer. These formats differ from camera to camera, but are called Camera RAW, or just RAW for convenience. You might think of RAW as a generic designation rather than a specific format, just as the trade name Heinz applies to all 57 varieties instead of just one.
A RAW file can also be likened to a digital camera's negative. It contains all the information, stored in 12-bit or 16-bit channels (depending on your camera), with no compression, no sharpening, and no application of any special filters or processing. In essence, a RAW file gives you access to the same information the camera works with in producing a 24-bit JPEG or TIFF file. You can load the RAW file into a viewer or image editor and then apply essentially the same changes there that you might have specified in your camera's picture-taking options.
Of course, to complicate things in the guise of attempting to simplify them, Adobe has introduced a new RAW format called DNG (for Digital Negative), which is offered as a common RAW format that should be compatible with any camera or software. So far, vendors aren't breaking their necks to support it. Another wrinkle is the decision by Nikon to encrypt the white balance data in its RAW files, making it more difficult for utilities from third-party software vendors to interpret all the information in Nikon's NEF files. Fortunately, it took only a few days for independent coders to report they'd "cracked" Nikon's encryption, so it remains to be seen how Nikon's move will affect those who work with NEF RAW files.
Some RAW formats, such as those deployed by Nikon and Canon for their highend cameras, are actually TIFF files with some proprietary extensions. That doesn't mean that an application that can read standard TIFF files can interpret them, unfortunately. Usually, special software is required to manipulate RAW files. If you're lucky, your camera vendor supplies a special RAW processing application that is easy to use and powerful. For example, Nikon offers Nikon View to read and manipulate its .NEF files, and Canon and Minolta both provide viewers for their RAW formats.
If you're not so lucky, you'll get a less capable utility, be asked to pay extra for it, or find that none at all is available. Photoshop CS 2.0 now includes a Camera RAW plug-in (which was formerly an extra-cost option with Photoshop 7) that works quite well. It can be used only with the particular digital cameras that Adobe has elected to support. The list is long, and includes many popular cameras from Nikon, Canon, and Minolta. You'll find that third parties also provide RAW decoders for specific camera models, such as YarcPlus and BreezeBrowser for Canon, and Bibble for the Nikon line. The great freeware Windows utility IrfanView can handle RAW files such as Canon's .CRW format. Mac users can work with programs like Lemke Software's GraphicConverter.
Many digital photographers shoot nothing but RAW images, preferring to do all their image processing later in their computer. Such photographers have several things in common: They're extremely fussy about their images, they have a ton of memory cards and almost unlimited storage space, and they're willing to spend a great deal of time working on their images. Be prepared to spend more time shooting the images, too, because RAW files can take a bit longer to store on your film card than your average JPEG file. (TIFF files can take even longer.)
For most of us, JPEG is fine most of the time. RAW is a good choice for exceptional photographs or exceptional needs (or if you just want to get the highest quality).
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