Adjusting brightness on Apple Studio Display CRT

[Anthony Kulesa]

The cube I recently purchased came with an Apple Studio Display (CRT). 
Unfortunately, the display is not as bright as I need it to be. There 
is no external adjustment on the display itself, and System Preferences 
(10.2.4) shows only a "Contrast" setting, not brightness. I have 
recalibrated and run Color Sync, but cannot seem to get a brighter 
setting. When I calibrate the display it flashes through several blank 
screens and I can see that the display has the ability to be brighter, 
so it's probably not a "weak tube" hardware problem. Anyone have any 
ideas about this? Thanks in advance.