From here on in make sure, you follow the instructions carefully.
Set your monitor contrast control to maximum and then adjust the
brightness control until the innermost grey square is only just visible
against the black surround. Squinting your eyes helps with this process,
as does keeping the room lighting at a low level or off.
If you're using a manufacturer supplied profile for your specific
make and model of monitor then in all probability the Phosphors will be
listed as "Custom". If this is the case leave well alone. If
you don't have a monitor profile choose either Trinitron or P22-EBU. I
keep getting asked -"how do I decide which is appropriate for my
monitor?" In truth, it matters little, but for those who are
determined to make the perfect choice; you can tell a Trinitron monitor
by simply looking at the display area. A Trinitron type monitor will
have two faint lines running across the display area approximately 1/4
from the top and 1/4 from the bottom. If your monitor has these lines
choose Trinitron, otherwise choose P22-EBU.
Begin by keeping the "View Single Gamma" selected
for now. Although keep in mind that this option "ONLY"
allows you to adjust the relative brightness of the monitor, not
neutralise any colour imbalances
Depending upon your computer type choose either the "Windows
Default" or "Mac Default" gamma. In reality,
this choice is not so important and you can choose either in the
knowledge that Photoshop will make the appropriate corrections when
necessary. Personally, and even though most of my work is now done on
the Mac platform I choose gamma 2.2
Adjust the slider until the inner grey square blends with the outer
frame, squinting slightly can help. Finally, deselect the "View
Single Gamma" checkbox.
This step is where we neutralise the colour imbalances inherent in
our monitor. Adjust each of the sliders in turn so as to blend the inner
square with its coloured surround. Again squinting is a great help.
Green is usually the most difficult to get right, but persevere. The
closer you get to a perfect match at this point the more accurate your
final profile will be.