Datacolor Spyder3 Elite Help Manual page 54

it is a reasonable digital approximation of how that control works on a CRT it is
possible that adjusting it will not affect the display of the Black/Dark Gray patches
shown here. You may find that one of the following situations occur:
* Even when you turn the control to its Minimum setting you still see all four blocks.
* Even when you turn the control to its Maximum setting you still can't see any
difference between the blocks.
For this reason, and others based on our testing of LCD monitors, we recommend that
you leave the Brightness control set to the Factory Default setting.
If you do elect to adjust the Brightness control of an LCD monitor be sure that you
don't confuse it with the Backlight control. Backlight controls and Brightness controls
are sometimes labeled with the same type of 'sun' symbol:
On an LCD display Black Luminance is sometimes controlled by the Brightness
control. The Brightness control is often identified with the sun symbol:
The Brightness control is sometimes labeled Black Level.
Set this control to the lowest setting that still allows you to see four separate blocks in
the Black Luminance visual guide:
You should be able to see four separate blocks inside the gray surround. If you do not
see four blocks, increase the Brightness control until you can just distinguish between
the leftmost (pure black) block and the adjacent (darkest gray) block. If adjusting the
Brightness control does not change the visibility of the four black blocks, then reset to
default value, and move to the next step of the calibration process.