Until recently, TIFF (Tagged Image File Format) had long been the preferred format of just about every digital-savvy professional photographer we know. It offered the highest quality (prior to the introduction of RAW formats), with no compression degradation. Also, TIFF is a universal file format, so it will automatically open in any imaging program. But TIFF also produces a very large and cumbersome file, and that in turn takes a long time to process and save within the camera. For instance, if a JPEG file takes 5 seconds to process and save, the same subject saved as a TIFF could take 30 to 35 seconds, or even more, depending upon the camera. In addition, unless you and the person to whom you are sending have broadband (fast Internet connections), TIFF files are way too large to routinely transmit via email or the Web.

As a rule, a TIFF file is roughly three times as large as the megapixel (MP) count of the camera. For instance, with a 5MP camera, the captured TIFF file will usually be at least 15MB. If you think about it, that makes a lot of sense. TIFF saves the full RGB image. In other words, in the preceding example, it will save 5MB of the red channel, another 5MB of green, and 5MB of blue. However, there is usually some overhead data (such as metadata—see the discussion later in the chapter), which can inflate the file size even further. (For more information on RGB, please go to Chapters 1 and 8.)

TIFFs used by digital cameras are lossless (as opposed to JPEG's lossy compression). However, in software, you will often have an option to compress TIFF files when you save them. Don't. The compression schemes used on TIFF are not only destructive, they can't be read by all programs.

Besides, the value of TIFF is it doesn't natively compress images, which is what assures higher image quality. Why mess with a good thing?

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