Desktop Color

Desktop Color Introduction Desktop color Memory Some of you have a computer system for a workstation. You should become familiar with color as it applies to computer-generated or desktop color. Desktop color is computer-generated color or various shades of grey from an IBM (PC) or Macintosh (MAC) computer systems. The color limitations of desktop color are the Random Access Memory (RAM) capacity of the computer, the Video Graphics Array (VGA) card, the scanner, and the monitor. Random Access Memory (RAM) determines the speed and power considerations for color. Color displays require more RAM than monochromatic displays. If your computer doesn’t have enough memory, you will experience delays in completing jobs that involve color. When adding color capabilities to your desktop system, reevaluate memory capacity and expand it if necessary. Video Graphics Array (VGA) Video graphics array (VGA) cards or Super Video Graphic Array (SVGA) cards control the resolution of computer monitors. Monitor resolution is stated in terms of dots per inch (dpi) for MAC monitors or picture elements (pixels) for PC monitors. You may use a VGA with color or black-and-white monitors. The VGA monitor has a resolution of 640 x 480 dpi. Super VGA increases the resolution to 800 x 600 dpi or 1024 x 768 (extended VGA). Scanners Scanners scan text and images and record them to memory. The type of scanner determines the resolution of the scanned image. Scanners are classified by image capture capabilities and whether they use the theory of reflectance (opaque copy) or the theory of transmission (transparent copy). There are hand-held scanners, sheetbed scanners, flatbed scanners, overhead scanners, slide scanners, and drum scanners. Most scanners connected to desktop computer systems use sensing elements called charged-couple devices (CCD). When light strikes CCDs, they retain voltage. The voltage apportions the amount of light striking the sensors and transfers this into reproduced copy. CCD scanners are of lower resolution than the photomultiplier tube scanners of Color Electronic Pre-press Systems. Continued on next page 2-36