> i recently bought an approximately 10 yrs. old commodore 1084s (pal)
> monitor for cutting video. the device is working fine except for having
> slightly too much green in the signal (using the video composite input -
> connected directly from my video board). i wonder if there is any
> possibility to adjust the intensity of each of the primary colours, in
> order to achieve a neutral display.

Sascha,
     There is a way to adjust that monitor. The setup procedure is
sometimes called color balance, white balance, CRT tracking, or just
greyscale adjustment. Video monitors are similar enough that this
generic information can be used with most of them. If you somehow mark
the controls before you make any adjustments, you can return them to the
starting point just in case you get "lost". A dab of ink from a marker
pen works well, but whatever you use, don't get any inside the control
itself. 
     If you've never adjusted a monitor before, keep in mind there are
dangerous voltages inside. The most obvious is the high voltage on the
picture tube, but you're not likely to lift the cap on the CRT during
your setup adjustments, so don't worry about that. The not-so-obvious
danger is that monitors and TV sets are "line operated" devices. That
means that the chassis is "hot" to ground at all times and poses a
lethal potential between chassis parts and other grounded objects around
it. Technicians use a 1:1 isolation transformer to reduce the risk of
shock and damage to equipment in the event of an accident. You can work
in reasonable safety if you keep other grounded objects (computer,
drives, etc.) away from your work area. Touch only with one hand (put
the other hand in your pocket... a habit I got into long ago) to reduce
the risk of electrical shock. Now, down to business...
     There are two sets of controls (usually three per set, but some
monitors have only two "drive" controls) to set the picture highlights
and lowlights separately. These controls set the voltage levels that
appear on each of the three color "guns" of the picture tube or CRT. The
highlights or bright areas of the image are set with the "background" or
"drive" controls, and the lowlights are set with the "screen", "cutoff"
or "G2" controls. Each manufacturer has their own names for these
controls, and of course each model has the controls in different places
physically. Some will place all controls on the CRT neck board (the
board that plugs directly onto the picture tube), and some will have
some or all on the main chassis, usually along the rear panel for easy
access. They are normally adjusted by use of a small, flat blade
screwdriver with an insulated (plastic) handle.
     To prepare the monitor for adjustments, turn the color level
(intensity) control all the way down. You don't want any color from the
video to offset the adjustments you are trying to make. All other
controls are set at normal viewing levels. Feed a video signal from a
video game or computer into the monitor so you have a fixed stable image
with an average of highlights and lowlights. A moving image from a TV
station is not a good choice because the forground/background levels
keep changing. As an alternative, don't connect a video signal, but just
use the brightness control on the front panel to run the "raster" (blank
screen) brightness up and down and make the adjustments for low and high
levels that way. It's not as "obvious", but it works.
     For only a minor correction of CRT greyscale, inspect the image to
see which areas of the picture are not neutral grey or white. If it's
the dark areas (low brightness off-color), use the "cutoff" control for
the predominant color (green in your case) and back that control down
until the screen looks grey. Adjustment of the other two cutoff controls
may be necessary to get it looking just right, but don't adjust any
control more than a few degrees. The adjustments are rather coarse and a
small control movement is all that's normally necessary. Color balance
offset in the dark areas will show up more than a similar offset in the
highlights, and some "drift" is normal as the monitor ages.
     If the white areas of the image are affected, back down the drive
control of the predominant color or raise the others to match so you
have a neutral white in the highlights. You may have to make minor
adjustments to both sets of controls so all levels of brightness are
neutral grey when you're done. Run the front panel user brightness up
and down to see if the raster "tracks" properly (doesn't change color
off neutral grey). 
     Some monitors have an internally adjustable brightness control that
sets a normal range for the front panel control and/or limits the
maximum brightness you can get without overloading the HV circuits. It's
normally located on the main board and may be called "sub-bright" or
"bright limit". It is normally set to produce a good picture with the
front panel brightness control set in the middle ("detent" position) of
it's range. 
     One last setting you might need to make at some point is the master
screen or G2 adjustment. It's a -very- coarse adjustment that sets the
overall level of brightness. As a tube ages, the G2 may need to be set
higher to compensate for a low-brightness problem. If this control is
set too high, the image may be too bright and/or take on a milky
appearance with faint diagonal "retrace" lines in the picture. If set
too low, you will not have enough brightness even with the front panel
brightness control at maximum. This master screen is on the flyback
(line output) transformer, the large black plastic block usually located
at the right rear of the main chassis. For identification purposes, note
the thick (usually red in color) wire that runs from the flyback to the
top of the picture tube. The two controls on the flyback are the focus
(top control) and master screen or G2 (bottom control).