After nearly a year of not being used, I got my 12" Apple RGB that I've had for 18 years out today. It has one problem--the focus seems to be quite off. Text and patterns are blurry (though readable) and it looks as though this display needs a good focus adjustment.

I've done focus adjustments on tons of 9" B&W screens, but never on a color monitor. Do I have to adjust red, green, and blue individually or is it all one control? Also, where is the control on the inside of the monitor to adjust this?

(I have a few extra displays that I may play around with first if need be--this particular 12" means a lot to me since I've had it so long).