Bit depth in relation to the quality of a digitized image

Bit depth in relation to the quality of a digitized image:

Bit depth refers to the number of color combinations available in an image's color pallette in terms of the number of 0's and 1's (or bits). Not all colors may be used in a single given image, but the bit depth still indicates the level of precision possible. The primary colors red, blue and green (known as color channels) are the basis for the combinations formed.
In a grayscale, the bit depth indicates the levels of possible shades.

Most images for digital cameras have an 8 bits per channel, so they use 8 1's and 8 0's. This consitutes 2 to 8th power which results in 256 total combinations/intensity values of the primary colors. A 24 bit depth pallette results in 16,777,216 different colors/combinations.

The human eye can only discern approximately 1 million different colors, making anything over 24 bit seem excessive. However a higher bit depth will assist of post processing includes enlarging the image for posters or other purposes. Bit depth can be down sized, but not up-sized from it's original image, therefore it is good to start out with a safe bit depth that will allow for some "breathing" room.

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