Page 29 - Enhancing CAD Drawings with Photoshop
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4386.book Page 12 Monday, November 15, 2004 3:27 PM
12 CHAPTER 1 THE BASICS
Figure 1.13
Drag selector from here…
Understanding
color values
…to here… …while noticing the color numbers here.
Table 1.1: Powers of 2
Power of 2 Number of Values Bit Depth Notes
2 1 2 1 Bitmap mode
2 2 4 2
2 3 8 3
2 4 16 4
2 5 32 5
2 6 64 6
2 7 128 7
2 8 256 8 Grayscale mode
2 9 512 9
2 10 1024 10
2 11 2048 11
2 12 4096 12
2 16 65,536 16 Limit of human perception of tonal differences
2 24 16,777,216 24 RGB (8 bits/channel)
2 32 4,294,967,296 32 CMYK (8 bits/channel)
