Datacolor Spyder3 Elite Help Manual page 99

Show RGB Sliders as an option in the Identify Color Controls screen
By default, this option is always turned off because most users do not need to adjust
the RGB Sliders of the display.
Users who really want to adjust the RGB Gain Controls on a display can turn this
option on. When this option is enabled, the user will be able to indicate to the program
that their display has RGB Gain controls. The application will then include a step
during calibration which assists the user in adjusting those controls.
Adjust White Luminance in software for displays that do not have a White
Luminance control
Some displays do not include a control for adjusting their White Luminance level. In
general, the White Luminance Control is a Backlight control on LCD monitors and a
Contrast control on CRT monitors.
If this option is turned on, the application will, if necessary, adjust (lower) the White
Luminance of the display being calibrated as part of the Look Up Table (LUT) that is
downloaded to the video card.
This can, however, result in some loss of dynamic range for the display. It is always
best to adjust White Luminance using a control on the display if possible.
Explanation of Delta E
White Point
This is a measure of how close the calibrated White Point is to the desired or target
White Point value. In Precision mode this is calculated as the difference in Lab color
space between the Target and Calibrated values for White Point and White
Luminance. In Visual Luminance mode this is not really Delta E but Delta ab
because it is calculated only as the difference in ab chromaticity (because there is no
numeric luminance target in Visual Luminance mode).
A Delta E of less than 3 is good. Less than 2 is quite good. Less than 1 is excellent but
not often achieved in practice.
Further Information
For information such as a list of Frequently Asked Questions and details on all
Datacolor products be sure to visit our website: www.datacolor.com/Spyder3