Glossary

color calibration

The process of adjusting a display's output characteristics such that you can reliably set the display's appearance to accepted standards.

color temperature

Definition of a monitor's white point. The definition of the color white is not absolute, and may exist somewhere in color space from red-white to blue-white. Expressed as a number in degrees Kelvin (K), color temperature refers to the amount of light radiated by an object known as a “blackbody” when heated to that temperature. Lower numbers, like 5000K, appear reddish whereas higher numbers, like 7000K, look bluish.

frame rate

The number of times a display's system hardware redraws pixels to the monitor screen in one second, measured in Hertz (Hz). With CRT monitors, low frame rates tend to flicker because the phosphor coating on the inside of the monitor tube decreases in intensity faster than the electron gun can refresh it. Flat panel monitors like the 1600SW, however, are not designed to work this way and therefore avoid flicker problems at all frame rates. Note that the graphics rendering rate is related to frame rate. The O2 workstation automatically adjusts its rendering speed according to the frame rate you choose. Other factors also apply.

gamma

The relationship between the video input signal level and the light output or intensity. CRT monitors have inherent non-linearities in how they display data. The amount of signal sent to the monitor is likely not the same as the amount displayed. For example, a strength 50 signal might be displayed at a level of 25, or a strength 90 signal might be displayed at a level of 30. Such nonlinear response is typical of CRT monitors and is called natural, or uncorrected, gamma. The 1600SW flat panel monitor does not have the inherent non-linearities of CRT technology, however it has a native (uncorrected) gamma setting of 1.8.

Computer system hardware permits gamma adjustment through the gamma Look Up Table (LUT.) The gamma value that a user chooses is called desired (or system) gamma, and the values applied to the gamma LUT are collectively called the correction gamma.

intensity (brightness)

The luminance, or brightness, of colors. The higher the intensity, the more light is radiated from a given surface area. Often this quantity is measured in candelas per square meter (cd/m2).

luminance

The perceived brightness of a surface. It typically refers to a weighted average of red, green, and blue color values that gives the perceived brightness of the combination. For video systems, luminance is the video signal that describes the amount of light in each pixel.

NTSC

A color television standard or timing format encoding all of the color, brightness, and synchronizing information in one signal. NTSC uses a total of 525 horizontal lines per frame, with two fields per frame of 262.5 lines each. Each field refreshes at 60 Hz (actually 59.94 Hz).

pixel

The smallest unit on the display screen grid that can be stored, displayed, or addressed. A display screen is divided into rows and columns of tiny dots, squares, or cells, each of which is a pixel. The resolution of a picture is expressed by the number of pixels in the display. The higher the number of pixels, the sharper the image.

presets

A way of creating color settings for each user account that can be loaded automatically when starting an X session.

refresh rate

See “frame rate”.