Trick is to set the brightness at factory default, usually 50%. Then
turn down the color all the way. Recieve normal video and cut the
picture control down until you can just barely see the picture, then,
if you have to do it in the back look at the lenses, or their
reflections in the screen. Try to equalize them at a barely seeable
level.

When you have the room dark and have a dark picture that looks pretty
much black and white, that is not overly tinted, then turn the picture
control to maximum. Note the color of the bright parts of the picture
at that time. Then you need to turn down the drive control for that
color. It could be a pot or it could be in software.

Just what year is this thing and what make and model ? And where are
you geographically ? Not that I'm coming over, but I want data on what
kind of different repairs are needed more often in different
climates.

It is very possible that your blue tube has bad coolant. Red plus
green plus blue make white, take the blue away you have yellow. Very
common in certain brands. Also in certain brands the blue is pushed
alot harder.

In Sonys especially, the blue is the hardest driven tube in it, and
the reason is that they use a different phosphor. It is not as
efficient, but it emits a very deep, pure blue color, somewhat like
comparing sky blue to midnight, or Navy blue. It is a deeper, truer
blue.

Like I said, what is the make and model of this thing ? Without that I
can go on for hours but there is no point.

JURB