Some of the real power in RAW files stems from a greater ability to hold color information (detail) than JPEG. A digital SLR records an image in three color channels: red, green and blue (RGB). The Nikon D90 records RAW in 12-bit color (4096 colors per color channel) while JPEG records in 8-bit color (256 colors per color channel).
This additional color information is especially important when an image needs altering or correction. During something as simple as resizing (making a file smaller or larger) computer software must make decisions about adding pixels or discarding pixels from an image. The more information held in the file (RAW wins this battle), the more accurate the decisions made by the software will be, preserving more detail.
In our huge library of photos, I am pretty confident to say that there will be well-composed images (not necessary well colored, focused or exposed) which we dearly want to save and improve on, as opposed to discarding them entirely. Well, this is the time when those RAW image format saves the day. In my new year's quest, I endeavor to spend and share with my readers a few tricks of correcting those problems with Aperture 2. If you are non-mac user, perhaps Photoshop is the platform to go. The concept is cross platform.
I know I praised the extensive use of JPEG in my previous article due to automatic Chromatic Abbrevation, but it would not do the Nikon D90 justice if we delve only in the realm of JPEG always, will we?