display monitor settings and
Setting monitor controls and target behaviour for monitor calibration
boils down to two things:
What is the equipment capable of without introducing side
What are you trying to do ?
There are three reasons you may want to adjust display settings and set
1) You want to change how non-color managed applications appear.
2) You want to change basic behaviour of the display that the profile
color management doesn't usually change, such as white
point and brightness.
3) You want to improve the behaviour of the device so that the normal
color management does a better job of controlling the
You can make adjustments to a display using it's controls and/or the
card LUTs. Generally the former are more powerful and have less side
effects. There can be exceptions though, for instance LCD's have no
native contrast control capability, only brightness, so contrast is
usually faked by manipulating the lookup curves, which can introduce
side effects. The same applies to white point control on an LCD (unless
R/G/B LED back lighting). So generally LCD displays are much less
flexible than CRT displays in targeting some non-native colorspace
without introducing side effects, so it is generally best to set all
the LCD controls except back lighting brightness to their default
Brightness depends on what you are trying to do. If you are trying to
do soft proofing for instance, you will have some brightness level in
mind dictated by the hard proofing booth you are comparing to, or the
ambient brightens level. For good color judgement and low fatigue it's
desirable that the display brightness roughly match that of the ambient
In terms of what you are trying to do, it comes down to what colorspace
you want the display to be, and how far from native for that display it
is. A CRT can be reasonably flexible in the behaviour it can be given
without side effects, an LCD less so. If you want to minimize artefacts
on an LCD you want to set the contrast and white points to their native
values (ie. where the monitor is not manipulating the digital signal
levels). It may not be easy to figure out what this is. In this
scenario you would probably only want calibration to set the transfer
characteristic and neutral axis, and leave the white point native.
For typical MSWindows/Linux this would probably be the typical CRT
("gamma") curve, or a gamma of about 2.4. For OS X it would probably
be a gamma of 1.8 for versions 10.5 or earlier, or 2.4 for 10.6 or
latter ("Snow Leopard").
The nominal white point of a display is D65 (set by Television
standards), and an LCD's native white point is somewhere near there,
but this is dictated by their backlight color. The CRT's will give
maximum brightness with a much higher white point (9000K or so), but
this can be reduced with fewer side effects (just reduced brightness)
using typical CRT controls.
If you have specific requirements (trying to do soft proofing) then you
may want to target a specific white point and brightness, and be
prepared to compromise other aspects of the display to achieve this. By
all means use the controls to move the display in the direction you
want to go, and then use the calibration curves to get there. If you
are moving far from native (especially on an LCD) you may find the side
effects unacceptable though.