you're gonna have to do a few adjustments after you do this. chances are your focus won't look as good. what I would do:
turn brightness and contrast controls to their centered positions.
for this next step, be sure your game has a screen with a black background.
-turn flyback Screen adjustment down until your screen brightness doesn't emit any color on portions of the game that have black -- you don't want any dark grey-ish/brown-ish raster on black.

(you might have to go back and forth between adjusting the Screen and Brightness until you get the desired effect.)
-adjust your Brightness control. you don't want a dark-dark picture, you want it to be just bright enough before blacks start showing up dark grey/brown.
for this step, make sure you have some form of basic text on the screen.
-gradually turn the Contrast back up, but don't go too high to where the colors will start overblowing. then gradually turn the Contrast back down until the color bleed on text is gone.
keep the text up, now start to adjust your Focus. go to the extremes with it, make the picture very blurry. dial it back to where the picture is in focus, and then turn the Focus knob both ways from the sweet spot... see if it's better or worse. (kind of like a vision test) keep doing this until you've attained the best results.
.... at least it's what I would do when I acquire a foreign monitor I've never touched yet.