Absolute Beginner's Guide to Digital Photography

CCD and Color: Using a Color Mask

CCDs are monochromatic devices. They simply measure the amount of voltage

acquired by each pixel. To capture color, a filter must be placed in front of the CCD

that separates visible light into primary colors. This filter is called a mask, or array.

The most popular mask in use today for digital cameras is called a Bayer mask.

CCD sensors that use a Bayer mask can only acquire one color per pixel (see

Figure 2.3).

18 ABSOLUTE BEGINNER’S GUIDE TODIGITAL PHOTOGRAPHY

FIGURE 2.3

The Bayer pat-

tern exists on

most digital

camera sensors.

Individual pix-

els are literally

painted with

red, green, and

blue colors.

Red Pixels

Bayer Mask Green Pixels

Blue Pixels

G R G R G R G R

G R G R G R G R

G R G R G R G R

G R G R G R G R

L G L G L G L G

L G L G L G L G

L G L G L G L G

L G L G L G L G