No two computer monitors are the same. Even if they're the same
make and model, they may be different ages, or made from components
with differing values, or viewed under different lighting
conditions, etc. The net result is that two people viewing the same
graphical image on different computers can have significantly
different experiences.
Thus the need to calibrate your monitor - to adjust it so that
its view approximates a standard. Unfortunately, manufacturers
take liberties when designing computer equipment, especially that
which is aimed at the consumer market - so the "calibration"
that can be done is gross, at best. But even that can offer a
big improvement.
The goal for this calibration process is to simply ensure that
the entire range of the "gray scale," from the blackest black to
the whitest white, is available, and spread uniformly.
This process will not address color calibration.
The gray scale shown above (and below) is adapted from the conventional
"Zone System" chart. On the Zone System scale, Zone I indicates
pure black, Zone IX pure white, and Zones II - VIII varying
uniformly spaced intermediate shades of gray. In addition to the
standard zones, the charts on this page further divide each zone into
four narrower gray zones.
To get a feel for the range of your monitor, first turn both
its brightness and its contrast controls, each in whichever
direction produces the darkest image, then turn both in the
opposite direction, to get the lightest possible image.
