Bit depth describes the number of bits used to store a value, with the number of possible values growing exponentially with the number of bits (Table 2.2). A single bit can store up to two possible values (black or white) while 2 bits can store up to four possible values (black, white, and two shades of gray), and so on (Figure 2.6). Digital image files are stored using either 8 or 16 bits for each of the three color channels that define pixel values (see “Color Modes” later in this chapter).
|Bits||Tonal Values Possible|
Figure 2.6. As the bit depth increases, the number of possible tonal values grows exponentially.
8 Bit vs. 16 Bit
The difference between an 8-bit and a 16-bit ...